A process for manufacturing a phase change memory cell, comprising the steps of: forming a resistive element; forming a delimiting structure having an aperture over the resistive element; forming a memory portion of a phase change material in the aperture, the resistive element and the memory portion being in direct electrical contact and defining a contact area of sublithographic extension. The step of forming a memory portion further includes filling the aperture with the phase change material and removing from the delimiting structure an exceeding portion of the phase change material exceeding the aperture.

1. Field of the Invention
The present invention relates to a self-aligned process for manufacturing a phase change memory cell and to a phase change memory cell thereby manufactured.
2. Description of the Related Art
As is known, phase change memory (PCM) elements exploit the characteristics of materials which have the property of changing between two phases having distinct electrical characteristics. For example, these materials may change from an amorphous phase, which is disordered, to a crystalline or polycrystalline phase, which is ordered, and the two phases are associated to considerably different resistivities.
At present, alloys of group VI of the periodic table, such as Te or Se, referred to as chalcogenides or chalcogenic materials, can advantageously be used in phase change cells. The chalcogenide that currently offers the best promises is formed by a Ge, Sb and Te alloy (Ge2Sb2Te5) and is widely used for storing information in overwritable disks.
In chalcogenides, the resistivity varies by two or more orders of magnitude when the material passes from the amorphous phase (more resistive) to the polycrystalline phase (more conductive) and vice versa. The characteristics of chalcogenides in the two phases are shown in FIG. 1. As may be noted, at a given read voltage, here designated by Vr, there is a resistance variation of more than 10.
Phase change may be obtained by locally increasing the temperature, as shown in FIG. 2. Below 150° C. both phases are stable. Above 200° C. (temperature of start of nucleation, designated by Tx), fast nucleation of the crystallites takes place, and, if the material is kept at the crystallization temperature for a sufficient length of time (time t2), it changes its phase and becomes crystalline. To bring the chalcogenide back into the amorphous state, it is necessary to raise the temperature above the melting temperature Tm (approximately 600° C.) and then to cool the chalcogenide off rapidly (time t1)
From the electrical standpoint, it is possible to reach both critical temperatures, namely the crystallization temperature and the melting point, by causing a current to flow through a resistive element which heats the chalcogenic material by the Joule effect.
The basic structure of a PCM element 1 which operates according to the principles described above is shown in FIG. 3 and comprises a resistive element 2 (heater) and a programmable element 3. The programmable element 3 is made of a chalcogenide and is normally in the polycrystalline state in order to enable a good flow of current. One part of the programmable element 3 is in direct contact with the resistive element 2 and forms the area affected by phase change, hereinafter referred to as the phase change portion 4.
If an electric current having an appropriate value is caused to pass through the resistive element 2, it is possible to heat the phase change portion 4 selectively up to the crystallization temperature or to the melting temperature and to cause phase change. In particular, if a current I flows through a resistive element 2 having resistance R, the heat generated is equal to I2R.
The use of the PCM element of FIG. 3 for forming memory cells has already been proposed. In order to prevent noise caused by adjacent memory cells, the PCM element is generally associated to a selection element, such as a MOS transistor, a bipolar transistor, or a diode.
All the known approaches are, however, disadvantageous due to the difficulty in finding solutions that meet present requirements as regards capacity for withstanding the operating currents and voltages, as well as functionality and compatibility with present CMOS technologies.
In particular, considerations of a technological and electrical nature impose the creation of a contact area of small dimensions, preferably 20 nm×20 nm, between the chalcogenic region and a resistive element. The problem is that these dimensions are much smaller than those that can be obtained with current optical (UV) lithographic techniques, which scarcely reach 100 linear nm.

Self-aligned process for manufacturing a phase change memory cell and phase change memory cell thereby manufactured


An apparatus for eviscerating poultry includes plural groups of cars driven around a monorail track by variable pitch augers which produce combined continuous and intermittent car movement. The groups of cars are brought to rest momentarily in front of machinery for performing various operations. At a first station, slaughtered birds are clamped at the shoulders, and brought to a supine position. At a second, the vent of the bird is opened. At a third, the viscera are removed by spoon. Inspectors then examine each bird at a fourth station, and final preparation is performed at a fifth before the birds are unloaded from the apparatus.

This invention relates generally to butchering, and more particularly to a machine for eviscerating poultry. Until fairly recently, poultry was eviscerated by hand. But growing labor costs, concerns over worker health, and the desire to minimize product contamination have by now made evisceration a job done primarily by machinery. The machines mimic what workers used to do: open the body of the bird at the vent without cutting the intestine (to avoid fecal contamination), then pull out the intestines, stomach and other internal organs through the opening. Certain organs--specifically, the heart, spleen, liver and gizzard--must remain associated with the carcass until it is inspected, because they may display signs of poor health, and because some may be included, with the neck, as giblets with the final product.
Every chicken produced in the U.S. is required to be visually inspected by a USDA inspector. At thirty-five birds or more per minute, the inspector's job is tedious and repetitious. Inspectors, like other workers, are subject to repetitive motion injuries, as they must manipulate the birds to get a good look at the interior of the body cavity and the organs. Inspection also is a limitation on line speed. It would therefore be beneficial to improve the way in which each bird is displayed to the inspector, and thus simplify his job by reducing or eliminating his need to handle the product.

Machine for eviscerating and displaying poultry for inspection


A method for forming a semiconductor device (10) includes providing a substrate (20) having a surface; forming an insulating layer (22) over the surface of the substrate (20); forming a first patterned conductive layer (30) over the-insulating layer (22); forming a second patterned conductive layer (32) over the first patterned conductive layer (30); forming a patterned non-insulating layer (34) over the second patterned conductive layer (32); and selectively removing portions of the first and second patterned conductive layers (30, 32) to form a notched control electrode for the semiconductor device (10).

When etching a polysilicon control electrode, the bottom corners of the polysilicon control electrode may be removed thereby undercutting or notching the control electrode. If the notching is uninhibited then the amount of undercutting is unknown and unpredictable, but, if controlled, the notching can be desirable. By predetermining the size of the notches in the control electrode, the gate length and the Miller capacitance of the polysilicon control electrode are desirably reduced.
As device dimensions shrink, there is a need to control the different threshold voltages (Vt) of the N-MOS and P-MOS devices. In addition, as the thickness of the gate dielectric decreases polysilicon depletion effects occur in the polysilicon control electrode. Substituting a metal material for polysilicon as a control electrode eliminates the polysilicon depletion effects. In addition, metal materials exist that have appropriate work function levels to set the desired threshold voltages for the NMOS and PMOS devices. Therefore, as the industry moves toward metal control electrodes, the benefits of undercutting a polysilicon control electrode are eliminated. Therefore, a need exists to be able to controllably decrease the gate length and miller capacitance of metal control electrodes.
Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve the understanding of the embodiments of the present invention.

Method for forming a semiconductor device having a notched control electrode and structure thereof


The present invention provides a reactor, which includes:

1. Field of the Invention
The present invention relates to an integrated chemical reactor for the production of hydrogen from hydrocarbon fuels such as natural gas, propane, liquefied petroleum gas, alcohols, naphtha and other hydrocarbon fuels and having a unique unitized, multifunctional structure. The integrated reactor offers significant advantages such as lower heat loss, lower parts count, lower thermal mass, and greater safety than the many separate components employed in conventional systems to achieve the same end. The integrated reactor is especially well-suited to applications where less than 15,000 standard cubic feet per hour of hydrogen are required.
The present invention also relates to the generation of hydrogen for use in industrial applications, as a chemical feedstock, or as a fuel for stationary or mobile power plants.
2. Discussion of the Background
Hydrogen production from natural gas, propane, liquefied petroleum gas (LPG), alcohols, naphtha and other hydrocarbon fuels is an important industrial activity. Typical industrial applications include feedstock for ammonia synthesis and other chemical processes, in the metals processing industry, for semiconductor manufacture and in other industrial applications, petroleum desulfurization, and hydrogen production for the merchant gas market. The demand for low-cost hydrogen at a smaller scale than produced by traditional industrial hydrogen generators has created a market for small-scale hydrogen production apparatus ( less than 15,000 standard cubic feet per hour (scfh)). This demand has been augmented by the growing enthusiasm for hydrogen as a fuel for stationary and mobile powerplants, especially those employing electrochemical fuel cells, which require hydrogen as a fuel.
Hydrogen is typically produced from hydrocarbon fuels industrially via chemical reforming using combinations of steam reforming and partial oxidation. This is typically achieved at scales larger than one ton per day using well-known process and catalyst designs. For several reasons, it is difficult to adapt these large-scale technologies to economically produce hydrogen at small scales. Typical industrial applications produce far more than 15,000 standard cubic feet per hour (xcx9c1 ton per day), and often employ catalytic steam reforming of light hydrocarbons in radiantly-fired furnaces. Steam reforming of hydrocarbons is illustrated for the simple case of methane below.
CH4+H2Oxe2x86x92CO+3H2
The above reaction is highly endothermic, and the reacting fluid must have energy transferred to it for the reaction to proceed. Further, the extent of the reaction is low at low temperatures, such that greatly elevated temperatures, often as high as 800xc2x0 C., are required by conventional systems to convert an acceptable amount of hydrocarbon to hydrogen and carbon monoxide. The catalyst employed in industrial reactors is typically composed of an active nickel metal component supported on a ceramic support.
The radiantly-fired furnaces employed in large-scale industrial reactors have many disadvantages that make them unsuitable for small-scale systems. The most important disadvantage is the very high temperature of the radiant burners and the gas contacting the reactor surfaces, which are usually tubular in form. The temperature of the radiant burners often approaches or exceeds the melting temperature of the alloy from which the tubes are fabricated. Melting of the tubes is prevented by the rapid endothermic catalytic reaction inside the tubes. If, however, the catalyst fails due to carbon formation, sulfur poisoning or other causes, then the tubes form what is referred to in the literature as a xe2x80x9chot spot,xe2x80x9d which greatly accelerates the failure of the reactor tube in question. In large-scale systems, careful monitoring and control of the furnace and tube temperatures as well as exceptionally rugged construction of the tubes makes the risks of hot spots acceptable. For systems producing below 1 ton per day, however, the complexity and cost of such safety measures can become prohibitive. Nonetheless, small-scale steam reformers utilizing radiant heat transfer are known and described, for example, in U.S. Pat. No. 5,484,577 to Buswell, et al. The extreme measures necessary to control the temperature in arrays of reformer tubes are likewise documented in U.S. Pat. No. 5,470,360 to Sederquist.
A means of transferring the necessary heat to the reacting gases without radiant heat transfer and its attendant risks, which is especially well-suited to small-scale steam reforming, is the use of compact heat exchange surfaces, such as arrays of tubes or finned-plates. The heat transfer mechanism in such devices is dominated by convection and conduction with minimal radiant transfer. An example of this approach is described in U.S. Pat. No. 5,733,347 to Lesuir, wherein finned plates are employed to increase heat transfer. Tubular compact heat exchangers for steam reforming are sold by Haldor Topsoe, Inc. of Houston, Tex.
Conventional hydrogen generation systems employing steam reforming of hydrocarbon fuels typically include three main reaction steps for producing hydrogen; steam reforming, high-temperature water gas shift, and low temperature water gas shift. The important reactions for methane are as follows:
CH4+H2Oxe2x86x92CO+3H2 steam reforming
CO+H2Oxe2x86x92CO2+H2 water gas shift
It is evident from the equation for steam reforming of hydrocarbon fuel that the principal products are hydrogen and carbon monoxide. The carbon monoxide may be converted into additional hydrogen via a catalytic reaction with steam (water gas shift reaction).
The water gas shift reaction is mildly exothermic and thus is thermodynamically favored at lower temperatures. However, the kinetics of the reaction are superior at higher temperatures. Thus, it is common practice to first cool the reformate product from the steam reformer in a heat exchanger to a temperature between 350xc2x0 C. and 500xc2x0 C. and conduct the reaction over a catalyst composed of finely divided oxides of iron and chromium formed into tablets. The resulting reformate gas is then cooled once again to a temperature between 200xc2x0 C. and 250xc2x0 C. and reacted over a catalyst based upon mixed oxides of copper and zinc. An example of this approach is given in U.S. Pat. No. 5,360,679 to Buswell, et al. In cases where an exceptionally pure hydrogen product is required, the temperature of the low-temperature shift converter is controlled by including a heat exchanger in the reactor itself, and an example of this approach is given in U.S. Pat. No. 5,464,606 to Buswell, et al. In all cases, the low temperature shift converter is quite large because of the poor catalyst activity at low temperatures.
In conventional systems, subsets of the process components are connected to one another via external plumbing; each component of the process being typically referred to as a xe2x80x9cunit process,xe2x80x9d in the chemical engineering literature. This approach is preferred in large, industrial units because standard hardware may be used. Owing to the large size of industrial units, the unit process approach also makes shipping of the components to the site of the installation feasible, as combinations of the components are sometimes too large to be transported by road or rail.
For systems producing less than 1 ton per day, however, the unit process approach has many disadvantages. The first disadvantage is the high proportion of the total system mass dedicated to the hardware and plumbing of the separate components. This high mass increases startup time, material cost, and system total mass, which is undesirable for mobile applications such as powerplants for vehicles.
Another disadvantage of the unit process approach in small systems is the complexity of the plumbing system to connect the components. The complexity increases the likelihood of leaks in the final system, which presents a safety hazard, and also significantly increases the cost of the assembly process itself. Moreover, the requirement that each component have its own inlet and outlet provisions also adds considerable manufacturing cost to the components themselves.
A third disadvantage is the high surface area of the plumbing relative to the unit process hardware itself, which means that a disproportionately large amount of heat is lost through the connecting plumbing in small scale systems. This can drastically reduce the thermal efficiency of the system and adds cost and complexity associated with adequately insulating the plumbing system.
A fourth disadvantage to the unit process approach in small-scale systems is that this approach requires a large volume to package, as each component and its associated plumbing must be accessible for assembly and maintenance purposes. This is particularly disadvantageous in space-sensitive applications such as building fuel cell power stations, fuel cell vehicle refueling stations, and fuel cell mobile powerplant hydrogen generation.
Hydrogen is typically separated from the other reaction products using pressure swing adsorption (PSA) technology. The design of these PSA systems is largely dictated by the catalyst chemistry employed in the steam reformer and the low-temperature water gas shift reactor. These catalysts, typically based on nickel metal in the former and copper in the latter case, are extremely sensitive to poisoning and deactivation by sulfur or molecular oxygen. Thus, the incoming feed gas must be carefully treated to remove these materials. Further, the system must protect the catalysts against these agents during startup, shut-down, and during intervals when the system is shut down. Especially in the case of molecular oxygen, exposure of the active catalyst can lead to catalyst damage and even create a safety hazard through pyrophoric oxidation of the finely-divided base metal catalysts.
Several steps are necessary in conventional systems to prevent damage to the reforming and Low Temperature Shift (LTS) catalysts.
(1) During operation, the incoming fuel must be treated to remove both sulfur and molecular oxygen. Sulfur in particular is generally reduced below 1 part per million, and more preferably below 100 parts per billion. This is typically achieved through a combination of a partial oxidation to remove oxygen followed by a hydrodesulfurization (HDS) process. Such systems typically require recycle of high-temperature, hydrogen-rich product gas to the inlet through the use of a gas compressor or a fluid ejector as exemplified by U.S. Pat. No. 3,655,448 to Setzer, U.S. Pat. No. 4,976,747 to Szvdlowski and Lesieur, and U.S. Pat. No. 5,360,679 to Buswell, et al. Because accurate temperature control is required for the HDS reaction, several heat exchangers as well as active temperature control logic circuits and flow control valves are also required. Provision of these reactors, heat exchangers, valves, as well as sensors and controls adds significantly to the complexity of conventional systems.
(2) Startup of conventional system requires bringing all of the components to near operating temperature, usually while blanketed in inert gas, then carefully initiating the reaction. Before the system is at operating conditions, full removal of sulfur and molecular oxygen is not guaranteed, so the process feed gas must be vented to the atmosphere, wasting fuel, generating air pollution, and creating a potential safety hazard while further increasing system complexity. Because the added components for fuel pretreatment add significant mass to the system, they also extend the warmup time required for hydrogen production. In situations with a variable hydrogen demand, this can create a need for extensive onsite hydrogen storage to supply the hydrogen demand while the system reaches operating conditions.
(3) During shutdown and periods when the conventional system is not operating, the reaction system is typically purged with inert gases under pressure. Alternatively, substantially leak-tight valves must be supplied to prevent ingress of atmospheric air to the unit with the resultant catalyst deactivation/damage.
For large-scale applications the added cost/complexity of the conventional systems does not adversely affect the system economics. When this traditional approach is applied to small-scale systems, however, the relative cost of these added components becomes disproportionately large, and the resulting hydrogen cost is dominated by the cost of the system. Accordingly, it is not advantageous to simply scale down large scale systems if a small scale system is desired.
Conventional steam reformer systems for natural gas and other light hydrocarbons fall into two broad classes. In the first, the reactors are operated at or near ambient pressure at low temperatures (typically less than 650xc2x0 C.). This is typical of conventional systems designed for small-scale applications producing impure hydrogen. For pure hydrogen to be produced, the reformer product must be compressed to high pressure for subsequent cleanup via PSA, metal separation membranes, or other conventional techniques. Because steam reforming creates additional moles of gas, the compression of the product gas is very energy-intensive and requires expensive and complicated compression and intercooling equipment. The second class of reformers is typically used in large-scale applications and is operated at high pressures (often above 20 bar). Because of the thermodynamics of the steam reforming reaction, these high pressure reactors must be operated at much higher temperatures, often approaching 900xc2x0 C., to attain adequate conversion of the hydrocarbon fuel to hydrogen. The higher temperatures and pressures require the use of more expensive materials of construction than are employed in the low-pressure systems, but this is more than offset by the reduction in reactor volume obtained due to enhanced chemical reaction rates. Unfortunately, in small-scale systems, the provision of compression and pumping equipment to deliver the reactants into a high-pressure (20 bar or higher) reactor can undesirably increase the cost of such a system.
Conventional pressurized steam reformer systems often are operated with very high temperatures in the combustion products used to heat the endothermic reaction zone. This high temperature allows a reduction in the amount of heat transfer area required to complete the reaction, and thus a reduction in reformer cost. Often, the mode of heat transfer to the wall of the tubes in the conventional reformers is a combination of radiation and convection, with the combustion carried out in a conventional premixed or diffusion-flame burner. The operation of the primary steam reformer with such high gas temperatures can lead to significant excursions in the reformer tube wall temperature due either to poor control of the distribution of the hot gases or to poisoning of the reforming catalyst. If the catalyst for the endothermic steam reforming reaction is locally-poisoned, the heat flux from the combustion products to the wall can form a local xe2x80x9chot spot.xe2x80x9d In either case, the increase in the reformer wall temperature can lead to premature reformer structural failure, presenting both a safety and an operational liability.
Conventional systems for hydrogen generation through steam reforming of hydrocarbons have several inherent deficiencies which make them ill-suited to economical small-scale hydrogen production. The first is the requirement for strict control of sulfur and molecular oxygen concentrations in the steam reforming and LTS reactors. The second concerns the problems with operation in the ambient pressure regime where the large volume of reformate gas must subsequently be compressed prior to purification. The third is associated with operating the reactor in the high-pressure regime typical of large-scale units where appropriate compression and pumping equipment adds considerable cost at small scales. The final shortcoming is the risk of overheating the steam reforming reactor structure due to the very high gas temperatures employed in the combustors in conventional systems and their reliance on radiant heat transfer, especially in high-pressure systems as employed in large-scale applications.
It has been recognized previously that integrating the elements of the unit process more closely beneficially reduces heat losses and improves compactness. U.S. Pat. No. 5,516,344 to Corrigan describes a steam reforming system wherein the unit process elements are integrated into a common mounting rack having a reduced requirement for insulation and having improved compactness. This approach, however, undesirably retains the multiple connections and extensive plumbing characteristic of the unit process approach. Moreover, because of its complicated packaging, the assembly of the Corrigan system undesirably presents a significant challenge.
Another attempt at improving compactness is described in U.S. Pat. No. 5,733,347 to Lesieur, wherein the primary reforming reactor and the catalytic burner are integrated into a planar reactor with compact heat transfer surfaces. This reactor requires separate heat exchangers to cool the gas after the primary reformer, as well as separate reactors for the water gas shift reaction. These all require interconnections, as do the array of planar reactors envisioned by Lesieur. These connections once again present the same drawbacks found in unit process reactor systems.
Accordingly, one object of the present invention is to provide a reactor for hydrogen production that avoids the problems associated with conventional systems.
Another object of the present invention is to provide a reactor for hydrogen production that is suitable for applications where less than 15,000 standard cubic feet per hour of hydrogen are required.
Another object of the present invention is to provide a reactor for hydrogen production that is safer and more cost efficient than conventional systems.
Another object of the present invention is to provide a reactor for hydrogen production that is less complex and is more space-sensitive than conventional systems.
Another object of the present invention is to provide for the production of hydrogen from a hydrocarbon fuel such as natural gas, propane, naphtha, or other hydrocarbons low in sulfur content ( less than 100 ppm sulfur by mass).
Another object of the present invention is to produce hydrogen which is substantially pure ( greater than 99.99%) by separating impurities using a pressure swing adsorption (PSA) system.
Another object of the present invention is to provide for the elimination of the pretreatment of the fuel feed to the steam reformer for the removal of sulfur and molecular oxygen.
Another object of the present invention is the provide for the operation of the system in a mesobaric regime, between 4 and 18 atmospheres, where appropriate fluid compression devices of small capacity, low cost, high efficiency and high reliability are readily available, and the resultant thermal efficiency of the hydrogen production system is very high.
Another object of the present invention is to provide for the feedback control of the delivery of fuel and/or air to a catalytic combustor in proportions such that the peak temperature of the gases entering the primary steam reformer does not exceed a safe maximum temperature determined by the metallurgy of the steam reformer.
Another object of the present invention is to provide for the operation of a steam reforming system without a low temperature water gas shift reactor.
Another object of the present invention is to provide for the operation of a hydrogen production system with feedback control of product carbon monoxide content.
Another object of the present invention is to provide a process having a simplified system construction, operation, and control resulting in low cost and relatively fast start-up and shut-down.
These and other objects have been achieved by the present invention, the first embodiment of which provides a reactor, which includes:
a unitary shell assembly having an inlet and an outlet;
a flow path extending within the shell assembly from the inlet to the outlet, the flow path having a steam reformer section with a first catalyst and a water gas shift reactor section with a second catalyst, the steam reformer section being located upstream of the water gas shift reactor section;
a heating section within the shell assembly and configured to heat the steam reformer section; and
a cooling section within the shell assembly and configured to cool the water gas shift reactor section.
Another embodiment of the present invention provides a reactor for the production of hydrogen from at least one selected from the group including natural gas, propane, liquefied petroleum gas, alcohols, naphtha, hydrocarbon fuels and mixtures thereof, the reactor including:
a unitary shell assembly having an inlet and an outlet;
a flow path extending within the shell assembly from the inlet to the outlet, the flow path including a convectively-heated catalytic steam reformer and a convectively-cooled water gas shift reactor.
Another embodiment of the present invention provides a method for producing hydrogen, which includes:
feeding at least one fuel selected from the group including natural gas, propane, liquefied petroleum gas, alcohols, naphtha, hydrocarbon fuels and mixtures thereof, into a reactor which includes a unitary shell assembly having an inlet and an outlet, and a flow path extending within the shell assembly from the inlet to the outlet, the flow path including a convectively-heated catalytic steam reformer and a convectively-cooled water gas shift reactor, whereby hydrogen is produced.
Another embodiment of the present invention provides a method for producing hydrogen from at least one fuel selected from the group including hydrocarbon fuel, natural gas, propane, naphtha, hydrocarbons with  less than 100 ppm sulfur by mass, and mixtures thereof, which includes:
producing hydrogen by steam reforming the fuel; and
substantially purifying said hydrogen with a pressure swing adsorption (PSA) system;
wherein prior to the producing, no pretreatment of the fuel to remove at least one impurity selected from the group including sulfur and molecular oxygen and mixtures thereof is carried out.
Another embodiment of the present invention provides a simplified hydrogen production process, which includes the catalytic steam reforming and subsequent high temperature water gas shift of low-sulfur ( less than 100 ppm by mass) hydrocarbon fuels followed by hydrogen purification through the pressure swing adsorption (PSA).
Another embodiment of the present invention provides an improved system for hydrogen generation through mesobaric (4-18 bar) steam reforming of natural gas, propane, naphtha and other low-sulfur hydrocarbon feedstocks.

System for hydrogen generation through steam reforming of hydrocarbons and integrated chemical reactor for hydrogen production from hydrocarbons

Abstract: a cooling section within the shell assembly and configured to cool the water gas shift reactor section. The present invention also provides a simplified hydrogen production system, which includes the catalytic steam reforming and subsequent high temperature water gas shift of low-sulfur ( less than 100 ppm by mass) hydrocarbon fuels followed by hydrogen purification through the pressure swing adsorption (PSA). The integrated reactor offers significant advantages such as lower heat loss, lower parts count, lower thermal mass, and greater safety than the many separate components employed in conventional and is especially well-suited to applications where less than 15,000 standard cubic feet per hour of hydrogen are required. The improved system also may be started, operated and shut down more simply and quickly than what is currently possible in conventional systems. The improved system preferably employs active temperature control for added safety of operation. The hydrogen product is of high purity, and the system may be optionally operated with a feedback control loop for added purity.


A hybrid non-abrasive electrical test contact element of a test socket is taught. Unlike cantilever contact elements of the prior art, the contact element of the present invention is able to contact a lead of an integrated circuit device under test without abrading the plating on the lead. This is achieved by the contact element possessing multiple loops to allow the tip of the contact element to move not only downwards, but also sideways in a rocking and non-sliding motion. The tip of the contact is also shaped to contact the lead at only a radius corner of each lead so as not to affect the solderability of the lead. In addition, tests have shown that the contact element of the present invention has at least twice the working life span compared to another contact element of the prior art.

Semiconductor integrated circuit devices (ICs or "chips") have to be tested for quality control as part of the manufacturing process. Automatic test equipment (ATE) are used to insert each chip (the "device under test" or DUT) into test sockets for testing. The ATE and their components are expected to last many thousands of test cycles. Any reduction in the cycle time due to equipment failure will contribute to increased costs for the manufacturer.
In addition, the ATE must not damage the chips in the testing process and an otherwise functional IC will be not be usable. This will also contribute to increased cost of manufacture.
During testing, proper electrical contact must be established and maintained between the leads of the DUT and the contacts of the test socket as this will affect the reliability of the test equipment to pick out faulty chips and not reject otherwise functional chips. Thus, this requirement of maintaining good electrical contact places demands on both the leads of the DUT and the test contacts used.
Now, metals are electrically conductive and the choice of the metal for use in the leads of a chip is a balance between cost, conductivity and suitability for use. Most metals are also subject to oxidation or corrosion and leads are usually plated to maintain electrical conductivity by preventing corrosion. Plating of leads also increases the hardness and wear resistance of the base metal and improves solderability at installation of the chip in a device.
Two main kinds of contacts are commonly used in ATE: straight "pogo" contacts with internal coil springs and bent cantilever contacts. The cantilever contact is exemplified by the invention by Yamaichi Electric Manufacturing Company and protected by a U.S. Pat. No. 4,997,378 (FIG. 1A).
In both kinds of contacts, a resilient means, be it the coil spring of the pogo contact or the loop of the cantilever contact, maintains a contact force against the lead of the chip to ensure good electrical contact. For unplated leads, it is desirable for the contact force to be large enough to allow the contact to break through a film of metal oxide on the lead. The contact may also be designed to permit a "wiping" action upon insertion of the DUT into the socket to scrub off this oxide film at the contact interface.
While this penetration or removal of the oxide film is desirable in unplated leads used in semiconductor chips of the past, this is not ideal for newer, plated leads as it will affect the solderability of the leads.
As the cantilever contacts of the prior art are designed to break through oxide layers, these contacts will also abrade the plating of these newer leads, affecting the quality of the soldering. The connection of the leads to the device in which the chip is installed will thus not be good. As such, an overly strong contact force by the contact of the ATE test socket is not desirable or suitable for chips with plated leads.
In addition, cantilever contacts of the prior art also do not have a long service life and must be cleaned and changed frequently.
Therefore, a need clearly exists for a contact that permits good electrical conduction between the lead of a device under test, with the test socket of automated test equipment, without compromising any plating on the lead as well as possessing a longer service life.


Systems and methods are described for concurrently applying loads to multiple test specimens. The systems and methods are useful for cyclical tensile loading of specimens such as in fatigue strength evaluations. The systems and methods are also useful for low frequency cyclical loading evaluations.

Acquiring fatigue crack growth rate (FCGR) data at low frequencies and near threshold values of a test specimen's stress intensity factor requires a significant investment in time and equipment. Generally, the total time required to conduct a test can be reduced by increasing the frequency of cyclical loading, but some situations require tests to be conducted at low frequencies. These low frequency tests can occupy a load frame for months. For over four decades, researchers have sought methods to test multiple specimens simultaneously as a means of obtaining test data faster, while performing the tests at an appropriate rate. As early as 1966, Robert E. Little of the University of Michigan proposed fatigue testing thin cantilevered coupons (0.84 mm) with a vibration table at either high frequency (approximately 1,000 Hz) or low frequency (28 Hz). As many as 40 specimens could be tested simultaneously in order to generate statistics to predict lifetimes. This was a simple pass/fail test, in which the specimens were fatigued for 106 cycles and inspected for the presence of cracks.
Fatigue testing in bending was also applied to multiple specimens of bone cement, polymer, and composite. A technique proposed by Kim et al. rotates thin flat specimens with dead weights of varying magnitude on each specimen to generate S-N (Stress versus Cycles-to-failure) curves. The cycle at which a given specimen fails is noted and the test is stopped after 106 cycles. For biological materials an immersion bath could be used.
Similarly, apparatuses described by Imig and Garrett and that of Slota and Wegman were designed to generate S-N curves, as the crack length is not monitored during the course of the fatiguing. Both techniques, however, are designed to test nonstandard specimens in tension. The "specimen" of Imig and Garrett is a titanium alloy (57.2 mm wide by 1220 mm long) studied for use in supersonic transport airplanes with stress concentrations machined into the test sections at specific intervals. After one of the test sections fails, that section is removed, the sheet spliced (bolted) back together, and the test resumed. Their system imposes very complex loading sequences to mimic real-time in-flight conditions. Furthermore, thermal loads and corrosive environments could be accommodated. Slota and Wegman offered no dimensions for their specimen, but it appears to be a flat bar. Further description was limited to an actuation method, which employed air pistons to load each specimen in tension, and an electrical switching mechanism that cyclically activated air pistons.
Ermi et al. in 1981 proposed linking eight miniaturized center-cracked tension specimens and loading them cyclically in tension. The load was applied by cyclically pressurizing helium in a chamber via a bellows at the top of the chain of specimens. The initial fatigue pre-crack (FPC) was varied to generate different starting values of the range of the stress intensity factor (ΔK). The linked specimens were fatigued for a pre-set number of cycles, the crack lengths measured, and fatigue crack propagation (da/dN) curves were compiled from data from all the specimens. Elevated temperature tests were possible with this test system.
Multiple specimen fatigue testing with crack growth monitoring is even less common. Hartt refined his multiple specimen fixture to include crack growth monitoring with direct current potential drop (DCPD). Initially, his system was designed to "run out" the crack, then the test was stopped, the broken specimen removed and replaced with a new or dummy specimen, then fatiguing was resumed, generating S-N data. Eventually, DCPD was added, and additional efforts generated da/dN curves. The loading source over time was the same. A servo-hydraulic actuator was employed to test eight specimens at low frequencies, but the control method changed from load to displacement control. Results on tests that used keyhole CT (compact tension) specimens, constant K (tapered) specimens, and bend specimens have been reported. Tests were conducted in both air and sea water to add an element of corrosion fatigue.
Each of these apparatuses was designed to address very specific issues, such as those relating to materials, environmental conditions, or loading mechanisms. Although satisfactory in many respects, a need remains for systems and related methods in which multiple specimens can be concurrently evaluated and particularly subjected to cyclical loadings such as in fatigue strength testing.

THE UNITED STATES OF AMERICA, AS REPRESENTED BY THE SECRETARY OF COMMERCE

THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY


Methods for producing a liquor having a high alcohol content are disclosed. Such methods employ mild conditions for increasing the alcohol content of the liquor, resulting in decreased levels of by-products that may adversely affect the taste. The high proof liquor generated by the methods disclosed herein is suitable for the preparation of alcoholic beverages such as brandy.

Brandy and other liquors are commonly produced from fruit by fermentation, followed by distillation and a reflux step to increase the alcohol concentration. In most conventional techniques, distillation takes place under relatively harsh conditions, which form by-products that adversely affect the taste. In an effort to alleviate this problem, a few methods have been developed for distillation under milder conditions. However, such methods typically involve additional steps, such as the introduction of an inert gas or maintaining vacuum conditions during distillation, which render the process more complicated and more costly.
Accordingly, there is a need in the art for more efficient methods of producing a quality high proof liquor suitable for the preparation of brandy and other alcoholic beverages. The present invention fulfills these needs and provides further related advantages.

Method for the production of high proof liquor


The present invention is a non-volatile memory device, wherein programming or erasing of memory cells is carried out by injecting or removing carriers in floating gates in the memory cells, comprising: a plurality of memory blocks each comprising a plurality of memory cells, respectively; and an erasing circuit for applying an erasing stress in units of the memory blocks and verifying that erasure has been completed in units of memory cells; wherein the erasing circuit applies an erasing stress to the plurality of memory blocks simultaneously until a past erasing stress minimum value for the plurality of memory blocks. According to the aforementioned invention, an erasing stress value, such as a number of erasing stress applications, is recorded for each memory block in past erasing operations, and the minimum erasing stress value of these erasing stress values is recorded. In the next erasing operation, an erasing stress is applied to a plurality of memory blocks in one batch, until this minimum erasing stress value is reached. Therefore, the erasing time can be shortened in comparison with a conventional method where application of erasing stress and erasure verification are repeated for each memory block, after respectively.

1. Field of the Invention
The present invention relates to a non-volatile memory device, such as a flash memory, or the like, and more particularly, to a non-volatile memory device whereby over-erasing is prevented and erasing time is shortened.
2. Description of the Related Art
Electrically rewritable non-volatile memory devices, such as a flash memories or EEPROMs, are capable of storing data in an unpowered state, and are widely used in portable telephones, portable information terminals, and the like. Flash memories, in particular, have been developed to high memory capacities, and erasing is carried out in high-capacity memory block units.
A memory cell in a non-volatile memory generally comprises: a control gate connected to a word line; a drain connected to a bit line; and a source connected to a source line. A programming operation (writing data 0) is carried out by applying a high voltage to the control gate and drain so that the memory cell transistor is switched conductive, and by setting the source to a low voltage so as to injecting the electrons passing along the channel to a floating gate. Supplying a prescribed voltage to the memory cell in order to carry out this program operation is known as applying "programming stress". When a program operation is executed, the memory cell transistor has a higher threshold voltage.
Moreover, in the erasing operation, the electrons are drawn away from the floating gate by setting the control gate to a low voltage or negative voltage, setting the drain to a floating state, and setting the source to a high voltage.
This operation of applying a prescribed voltage to the memory cell is known as applying "erasing stress". When an erasing operation is carried out, the memory cell transistor has a low threshold voltage.
In the read-out operation, by controlling the word line to an intermediate voltage between the threshold voltages of the programmed and erased transistors, the memory cell transistors in a programmed state are switched OFF (non-conductive), whilst the memory cell transistors in an erased state are switched ON (conductive), and this presence or absence of current according to the OFF or ON state of the transistors is detected by means of the bit line.
In the erasing operation, after the aforementioned erasing stress has been applied for a prescribed unit time, the memory cell being erased is read out to check (verify) if its threshold voltage is less than the erasure verification level. By repeating the operations of applying this erasing stress and verifying erasure, a suitable erasing operation is performed. In a flash memory using a non-volatile memory, erasing is performed for a whole memory block comprising a plurality of memory cells, in one batch.
In the aforementioned erasing operation, if an erasing stress is applied more times than necessary, the threshold voltage of the memory cell transistors will become negative, meaning that even if the word line is in an unselected state (L level), the memory cell connected thereto will be switched ON, which is undesirable. This state is known as "over-erasing", and must be avoided in the erasing operation.
On the other hand, as memory capacity increases, there is a tendency towards increased variation in the number of applications of, and time period of, erasing stress which is required for each memory cell or each memory block. In general, an erasing operation is carried out by applying an erasing stress to a plurality of memory cells in one batch. Therefore, if erasure has been completed in one portion of the memory cells but it has not been completed in the other memory cells, the erasing stress will still be applied equally to the memory cells which have been completely erased. Consequently, a portion of the memory cells will be "over-erased". The greater the number of memory cells to which an erasing stress is applied in one batch, the greater the variation in the number of erasing stress applications required, and hence the greater the probability of over-erasing.
In order to avoid these-over-erasing problems, conventionally, a memory region is divided into a plurality of memory blocks, and the operations of applying an erasing stress and verifying erasure are repeated for each memory block. By reducing the number of memory cells which are erased in a single operation, it is possible to suppress variation in the threshold voltages of memory cells after application of the erasing stress, thereby avoiding the problems of over-erasing.
However, if a method is adopted whereby the operations of applying erasing stress and verifying erasure are repeated for each memory block, individually, then the time taken to erase all of a plurality of memory blocks will become long. In flash memories, in particular, where high memory capacity is being developed, this lengthening of the erasing time is a problem which must be resolved.


An intercalation compound of general formula Na.sub.x K.sub.1-X Z.sub.y, wherein Z is a carbon or a polymer with a cyclic, particularly aromatic unit, as base unit; 0<x<1; and 2.ltoreq.y.ltoreq.6. A method for preparing the compound is also described, as well as the use thereof, particularly in pyrotechnics and in lithium batteries.

It is known to prepare materials capable of generating a sufficient amount of heat on contact with air to be able to be used in pyrotechnics. These materials are generally provided in a pulverulent form and are in particular inorganic compounds.
Among inorganic compounds, alloys and inter-metallic compounds can a priori offer good prospects. Calcium-based alloys are advantageous, for example: they are hard, brittle, can easily be detrimentally affected by water and exhibit exploitable melting temperatures. By way of illustration, the melting temperature of Ca.sub.2 Sn is 1120.degree. C. and that of CaSn.sub.3 is 627.degree. C.
Mention may also be made of calcium-magnesium alloys MgCa or Mg.sub.2 Ca for which the melting temperatures are 517 and 714.degree. C. respectively. Mention may further be made of calcium-zinc alloys, for example ZnCa for which the melting temperature is 385.degree. C.
The enthalpies of reaction (.DELTA.H) are as follows, assuming that the oxides are formed according to a reaction of the type ##EQU1##
______________________________________ 1 .DELTA.H (kcal .multidot. mol.sup.-1) ______________________________________ Ca.sub.2 Sn 2 -442 CaSn.sub.3 3.5 -568 Mg.sub.2 Ca 1.5 -449 MgCa 1 -300 ZnCa 1 -235 ______________________________________
Alloys based on sodium and on potassium have been widely studied for possible pyrotechnic applications. It has thus been possible to demonstrate that some of these alloys, for example the sodium-potassium alloy containing 50-80% by mass of potassium, may be potentially advantageous in pyrotechnics. This is because some of them react in the presence of oxygen or of water with a strong release of heat.
As regards the intermetallic compounds formed with sodium or potassium, their reaction with air is less violent that when Na or K are alone, which is per se a positive point.
Titanium forms a great many binary or ternary alloys with most of the elements of the periodic classification (nouveau traite de Chimie Minerale [New Treatise on Inorganic Chemistry], Paul Pascal, Masson).
Metallic titanium has the property of spontaneously oxidizing in the presence of oxygen, releasing a large amount of heat.
Moreover, much work has been carried out into the study of coruscative materials (this concerns intermetallic combined materials, that is to say that, after having reached the reaction temperature, these products are capable of releasing large amounts of energy).
Mention may be made, for example, of:
______________________________________ Ignition Reaction Enthalpy % temperature temperature measured Material by weight (.degree.C.) (.degree.C.) (J.g.sup.-1) ______________________________________ Ti Sb Pb 48 23 29 570 1010 1045 Ti Te 27 73 433 870 815 ______________________________________
Patents WO 089/10340 and U.S. Pat. No. 4,830,931 relate to processes for the activations of metal surfaces in order to render them pyrophoric.
The basic principle is the attack on the metal surface by a mixture of a metal and of its chloride, at a temperature such that the substrate remains in the solid state and that the mixture is in the liquid state. The reaction is long, since it lasts several tens of hours.
The metal, thus covered with an intermetallic layer, is subsequently activated by a sodium hydroxide solution.
The metal which has become pyrophoric must then be stored in a liquid of low volatility (examples: fluoroethane, nonane, glycerol).
However, it is expensive to prepare these compounds and the latter can thus be exploited industrially only to a fairly limited extent.
Compounds which have formed the subject of other studies in this field are metal pairs which are in a position, when the reaction temperature is reached, to release relatively large amounts of energy with the formation of an alloy.
It is thus necessary to transmit a sufficient amount of energy to these materials in order for the melting temperature of one of the metals of the pair to be reached and for the reaction to take place.
Explosive charges are generally used.
The exothermic reaction is brief.
However, these compounds are also expensive and, for this reason, can also be exploited industrially only to a limited extent.
Lithium-based alloys are also well known. Their high reactivity in the presence of moist air, for example, is known and is profusely described by J. C. Bailar, in "Comprehensive Inorganic Chemistry", Volume 1, 1973, 335-37, F. A. Cotton and G. Wilkinson, in "Advanced Inorganic Chemistry", 1972, 189-91 and F. E. Wang and M. A. Mitchell, in "J. Less Common Metals", 1978, 61, 237.
It is noted that organometallic compounds are often far removed from pyrotechnic applications. This is because they often exhibit the disadvantage of reacting violently in the presence of water. Now, the water content in air depends essentially on the weather conditions. It is therefore very clearly understood that the result of bringing these compounds into contact with air is uncertain and that, for this reason, these compounds are rather far removed from pyrotechnic applications.
In reality, in this field, there is interest in particular in compounds which give rise to reactions involving atmospheric oxygen (optionally nitrogen), in order for the product to retain an equivalent performance whatever the surrounding conditions.
It is a question of generating heat in the atmosphere by distributing therein a pulverulent product capable of spontaneously oxidizing. More specifically, it is a question of heating a volume of air (typically 1000 m.sup.3) while avoiding an excessively high temperature peak (so-called "thermal peak").
In this respect, tests have shown that the majority of the inorganic compounds indicated above exhibit in particular the following disadvantages:
their duration of combustion is too brief, PA1 the temperature reached is too high. PA1 it reacts instantaneously with air, that is to say in less than 0.5 second, PA1 its duration of combustion with air is greater than 5 seconds, PA1 its calorific value is high, PA1 its resistance to ageing is good, PA1 it is nontoxic, PA1 it is prepared by means of a process which can be readily industrialized, PA1 its cost is moderate, PA1 it does not give rise to a violent reaction when it is immersed in water. PA1 Z represents carbon or a polymer with a cyclic unit, in particular an aromatic unit, especially a polymer in which the basic unit is C.sub.6 H.sub.4 ; EQU 0<x<1, PA1 y being able to be an integer or a noninteger.
In addition, these compounds can be improved from the viewpoint of their intrinsic properties, for example their toxicity. Moreover, it would also be desirable to have better control over all the values related to their reaction with air, namely the energies and the durations of this reaction.
From a practical viewpoint, it would also be appropriate to develop a process for the manufacture of such compounds which is simpler and faster than those which currently exist.
Some intercalation compounds of graphite, namely those of heavy alkali metals, have been known since 1926 [K. Fredenhagen and G. Cadenbach, Z. anorg. allgem. Chemie (1926) 158].
Finally, the description of the state of the art can be completed by the citation of the document U.S. Pat. No. 3,160,670, which teaches the use of KC.sub.8 as a catalyst for chemical reactions.

Intercalation compounds, method for preparing them and use thereof, particularly in pyrotechnics


A connector assembling construction includes a movable connector (20) provided on a module (M) such as an instrument panel of an automotive vehicle and a waiting-side connector (40) provided on a body (B) and having a receptacle (41) for receiving the movable connector (20). The movable connector (20) and the waiting-side connector (40) are connected as the module (M) is assembled with the body (B). Rib-shaped slanted surfaces (28, 30) project within the entire width range and within the entire height range of a connecting surface of the movable connector (20). The slanted surfaces (28, 30) are arranged at positions near opposing ends of the connecting surface, and have gradients to increase projecting amounts thereof as they extend in from the ends of the connecting surface.

1. Field of the Invention
The invention relates to a connector assembling construction for connecting a module-side connector and a body-side connector as a module such as an instrument panel is assembled with a body in an automotive vehicle.
2. Description of the Related Art
Modules, such as an instrument panel, must be assembled with the body of an automotive vehicle. The module and the body have connectors that must be connected with one another as the module and the body are assembled. However, connecting parts of the connectors are hidden between the module and the body and may be displaced from each other during the assembly process. As a result, assembly efficiency may be reduced. U.S. Pat. No. 6,878,001 discloses a connector assembling construction which is designed in view of this problem. The connector assembling construction of U.S. Pat. No. 6,878,001 has a waiting-side connector with a receptacle and a tapered guide is formed at the opening edge of the receptacle to correct a displacement during the connecting operation. According to this assembling construction, the front end of a movable connector contacts the slanted inner surface of the guide during a connecting operation. As a result, the front end of the movable connector moves orthogonal to a connecting direction and into a proper insertion position as the connecting operation progresses.
However, a correctable range is determined by the size of the guide in this construction. Thus, an attempt to miniaturize the guide restricts the correcting displacement, and it is difficult to miniaturize the entire connector.
The invention was developed in view of the above, an object is to miniaturize a connector while correcting displacement during connection.


A beamsplitter includes a first fluoride prism and a second fluoride prism. A coating interface is between the first and second fluoride prisms, wherein an overall R(s)*T(p) function of the beamsplitter varies no more than ±2.74% in the range of 40-50 degrees of incidence.

1. Field of the Invention
The present invention pertains to optics, and in particular, to beam splitters used in microlithography.
2. Related Art
Photolithography (also called microlithography) is a semiconductor fabrication technology. Photolithography uses ultraviolet or visible light to generate fine patterns in a semiconductor device design. Many types of semiconductor devices, such as, diodes, transistors, and integrated circuits, can be fabricated using photolithographic techniques. Exposure systems or tools are used to carry out photolithographic techniques, such as etching, in semiconductor fabrication. An exposure system can include a light source, reticle, optical reduction system, and a wafer alignment stage. An image of a semiconductor pattern is printed or fabricated on the reticle (also called a mask). A light source illuminates the reticle to generate an image of the particular reticle pattern. An optical reduction system is used to pass a high-quality image of the reticle pattern to a wafer. See, Nonogaki et al., Microlithography Fundamentals in Semiconductor Devices and Fabrication Technology, Marcel Dekker, Inc., New York, N.Y. (1998), incorporated in its entirety herein by reference.
Integrated circuit designs are becoming increasingly complex. The number of components and integration density of components in layouts is increasing. Demand for an ever-decreasing minimum feature size is high. The minimum feature size (also called line width) refers to the smallest dimension of a semiconductor feature that can be fabricated within acceptable tolerances. As a result, it is increasingly important that photolithographic systems and techniques provide a higher resolution.
One approach to improve resolution is to shorten the wavelength of light used in fabrication. Increasing the numerical aperture (NA) of the optical reduction system also improves resolution. Indeed, commercial exposure systems have been developed with decreasing wavelengths of light and increasing NA.
Catadioptric optical reduction systems include a mirror that reflects the imaging light after it passes through the reticle onto a wafer. A beam splitter cube is used in the optical path of the system. A conventional beam splitter cube, however, transmits about 50% of input light and reflects about 50% of the input light. Thus, depending upon the particular configuration of optical paths, significant light loss can occur at the beam splitter.
In UV photolithography, however, it is important to maintain a high light transmissivity through an optical reduction system with little or no loss. Exposure time and the overall semiconductor fabrication time depends upon the intensity or magnitude of light output onto the wafer. To reduce light loss at the beam splitter, a polarizing beam splitter and quarter-wave plates are used.
Generally, polarizing beam splitters are designed for maximum optical throughput, but without a particular attention to the apodization they impose on the pupil of the projection optics. In optical systems having low numerical apertures (i.e., on numerical apertures corresponding to a lower range of operating angles at the beam splitter coating), this is not a significant problem, since the natural bandwidth of the coating is typically large enough to cover the requirements. However, at higher numerical apertures, the coating designs become more complex, and result in an increase in undesirable performance fluctuations over the angular range of operation.
Accordingly, what is needed is a beamsplitter with a relatively flat apodization function over a wide angular range that is usable in UV photolithography.

Ultraviolet polarization beam splitter with minimum apodization


An electroconductive composite material composed of a three-dimensional continuum of a porous metal with the pores filled with graphite and a resin, having a good heat resistance, wear resistance, strength and thermal conductivity, having a light weight, and particularly useful as electric armature brushes and other electric sliding elements.. A process of producing the composite material comprises the steps of: filling pores of a three-dimensional continuum of a porous metal with a pasty mixture composed of graphite, a binder, and a solvent; treating the continuum for volatilization of the solvent; and then, forming and heating the continuum.

1. Field of the Invention
The present invention relates to a composite material for sliding parts such as pulleys, retainers, sliding parts housings and friction members, and for sliding parts of electric armatures, such as commutator brushes.
2. Description of the Related Art
Conventionally, sliding parts such as pulleys, retainers, housings and friction members are made of resin. Resin is lightweight and easy to work, allowing inexpensive manufacture.
Resin, on the other hand, is inferior in heat resistance, wear resistance, strength and heat conductivity. Therefore, sliding parts made of resin have a short lifetime.
To avoid these drawbacks, a resin mixed with a metal powder is used. Metal is superior to resin in heat resistance, wear resistance, strength and heat conductivity. The mixing of a metal powder in a resin is intended to impart these characteristic properties of metal to the mixture.
The mixture, however, is heavy because a great amount of metal powder must be added to a resin to avoid the above drawbacks.
Conventional electric armature brushes are mostly composed of a metal powder (predominantly of Cu) for providing electric conductivity, graphite for lubrication, and a binder. Among these components, the metal powder mostly has an adverse effect on wear resistance, and therefore, is preferably present in as small an amount as possible, though it is necessary to provide good electric conductivity.
The metal is mostly used in the form of a powder (such as electrolytic powders, atomized powders, and flake powders) in order for the metal to disperse well over the mixture. The metal powder, however, is present as discrete particles in the mixture and causes the mixture to be less conductive than expected from the metal amount contained in the mixture, so that an undesirably great amount of metal powder is unavoidably added in the mixture to ensure good conductivity, even though the lifetime (wear resistance) is reduced. Thus, the conventional electric armature brush has a poor resistance to wearing, because of a great amount of metal powder contained therein.

Composite material and process of producing same


The operation of a device by a user is detected, and one or more speech input executing commands corresponding to the operated device are provided to the user, e.g., by speech or by being displayed on a screen. Speech input guidance may be stopped if it would interfere with an audio or image output of an operated device, or if a count of guidance speech outputs exceeds a predetermined number.

1. Field of the Invention
The present invention relates to a speech input guidance method for notifying a user of features that are operational by speech for a speech input device for allowing various types of device operations by speech, and a speech input guidance apparatus for executing this method.
2. Description of the Prior Art
As a result of recent diversifying features of various types of devices, a single device can include an extremely wide variety of features and provide a user of the device with great convenience. On the other hand, because it is necessary for a user to select an operation unit which provides a specific feature from many operation units, such as switches, and to operate the operation unit to enter an operation instruction, the difficulty of selecting an operation unit and remembering an order of an operation increases. As a result, the number of devices for setting an order of displayed features from a higher priority on a liquid crystal display, for example, allowing a user to select a displayed feature with a touch panel or a cursor indication of a remote controller, and finally conducting the specific feature is increasing.
For example, a desired destination setting means allows a selection from among various methods, such as finding a specific place while scrolling to display from a wide area map to a zoomed map sequentially, narrowing down sequentially from a state or a prefecture to a specific place, entering a phone number, entering a zip code to show a map for a neighborhood of a specific place and finding the place while scrolling the map, specifying a category of a specific facility, and then specifying an area to search for the facility, selecting from a list of places which were previously set as destinations, visited, or registered, and using alphabet keys for direct entry. Operations are provided on selection screens and scroll screens displayed sequentially for the individual means, the specific place is found, and finally the place is established on a vehicle onboard navigation device.
It is a proper method for operating many features to specify precisely a desired feature from among many features, and to conduct a setting operation for this feature while various selection screens are being shown. However, as features become further diversified and complicated, it becomes ambiguous what operations are to be sequentially conducted for a desired operation, and it is required to repeat various operations for the setting.
Because a user who operates vehicle onboard devices such as a vehicle navigation device or a vehicle audio device is most often a driver, it is required for the user to operate these vehicle onboard devices so that the operation does not affect driving, which the driver should concentrate on most. However, as the different types of devices have included more functions as described above, because it is virtually impossible for a user to select and to operate a desired feature button from many feature buttons, or to conduct an operation for sequentially selecting function menus shown on a screen, the user has to do so while stopped.
As a consequence, it is gradually becoming common to introduce speech recognition technology, which has been researched and developed rapidly in recent years, for providing an instruction by means of speech for different types of operations. With this technology, when the phrase "Nearby Seven-Eleven" is simply uttered while a speech input device is being ON, a navigation device recognizes "nearby", determines that a search for a specific facility is requested, also determines that a search area should be as close to a current position as possible, and selects a search range so as to search on a guide route as much as possible, and simultaneously in an area ahead of the current position when it is discriminated that this vehicle is traveling along the guide route. The navigation device recognizes a phrase, "Seven-Eleven", to search by category, selects a convenience store category from different types of categories, and searches for facilities of "Seven-Eleven" in the category. When a search result is obtained, the result is shown on a map on a screen based on position data, and guidance such as "There is a Seven-Eleven on the left side 700 m ahead" is provided by speech if necessary.

Method and apparatus for speech input guidance


Disclosed is an optical printed circuit board (PCB) having a multi-channel optical waveguide, which comprises: an optical waveguide having an optical path for transmitting light beams; a groove for penetrating the optical waveguide; and an optical interconnection block inserted in the groove and connected to the optical waveguide to transmit the light beams, wherein the optical interconnection block includes an optical fiber bundle bent by the angle of 90°. The optical interconnection block connects a plurality of multi-layered optical waveguides to transmit light beams to the optical waveguides. The optical fiber bundle is installed as a medium of the multi-channel optical waveguide in the optical PCB.

(a) Field of the Invention
The present invention relates to an optical printed circuit board (PCB) and an optical interconnection block using an optical fiber bundle. More specifically, the present invention relates to an optical printed circuit board with a built-in optical waveguide, and an optical interconnection block in optical PCB based optical interconnectors.
(b) Description of the Related Art
In general, a printed circuit board (PCB) represents a phenol-resin or epoxy-resin circuit board on which various components are mounted and paths for interconnecting the components are fixedly printed. As to a PCB manufacturing process, a thin film of copper is attached to one side of a phenol-resin insulation board or an epoxy-resin insulation board, the thin film is etched according to predetermined patterns to configure a desired circuit, and holes for mounting components are generated.
The PCB can be classified as a single layer substrate, a double layer substrate, and a multi-layered substrate, and the multi-layered substrates are used in high-precision products because the increased layers allows more installation capacity. A multi-layered PCB represents a printed circuit board having conductive patterns on at least three layers that are separated by insulation matter.
The copper film is patterned to form an inner layer and an outer layer on the PCB in the conventional PCB manufacturing process, but high polymers and glass fibers have been recently used to insert optical waveguides into the PCB, which is referred to as an electro-optical circuit board (EOCB). The EOCB has optical waveguides and glass substrates in addition to the copper circuit patterns and allows both electrical signals and optical signals so that the EOCB may interface very high-speed data communication executed on the same board by using optical signals and may convert the optical signals into electrical signals and store data or process signals.
Various coupling methods for connecting the optical signals on the multi-layered PCB have been proposed, and general multi-channel interconnection methods include the direct writing method, the beam reflection method, the reflection mirror using method, and the direct coupling method.
FIG. 1 shows a conventional optical PCB and an optical connection structure using an optical interconnection block.
Referring to FIG. 1, a via hole is generated in the optical PCB 1, and an optical connection rod 4 having a reflection mirror with the angle of 45° on the top thereof is inserted into the via hole. In this instance, the reflection mirror is formed by coating silver (Ag) or aluminum (Al) on the optical connection rod 4, or the same is configured by attaching an additional reflection mirror thereon. Light beams output by a light source of an optical transmitter are reflected by 90° on the mirror with the angle of 45° to be transmitted through an optical waveguide 2 to a mirror with the angle of 45° of the optical connection rod 4 at the side of an optical receiver, and the light beams, again reflected by 90° on the mirror, are transmitted to a photo-detector 6 of the optical receiver.
For example, when electrical signals are applied to the optical transmitter by a process board, the electrical signals are converted into optical signals by a laser diode 5, the optical signals are transmitted through a lens to the left reflection mirror to be reflected, the reflected optical signals are provided through the optical waveguide to the right reflection mirror to be reflected again, and the reflected optical signals are transmitted through another lens to a photodiode 6 functioning as a photo-detector in the optical receiver. In this instance, the optical waveguide transmits the light beams through a multi-mode polymer waveguide core with low loss, and a waveguide clad is formed around the core. Therefore, the electrical signals provided by the left processor board are converted into optical signals and transmitted to the right processor board, and are then converted into electrical signals again.
In the prior art, when the vertical cavity surface emitting laser (VCSEL) 5 emits light, a micro-lens gathers the light and transmits the same to the optical waveguide through a PCB hole or an optical via hole 3, and the light is transmitted to another layer through the hole. A silicon optical bench (SiOB) generally referred to as a silicon wafer is formed on the PCB 1, and a polymer substrate can be used for the SiOB. The optical waveguide transmits the light provided by the VCSEL through the lens to another optical waveguide on another layer.
The VCSEL represents a light source for vertically outputting laser beams on a substrate and is used to transmit and amplify optical data. LEDs and edge emitting laser diodes (LDs) have been widely used as the light sources, although surface-emitting lasers (SELs), developed in the nineties, have recently come to be used instead of the LEDs and the edge emitting LDs. The VCSELs are used for optical fiber communication, interface, and parallel processing of large amounts of information.
FIGS. 2A and 2B show conventional optical interconnection blocks configured by optical interconnectors for transmitting light beams of various channels in parallel.
Referring to FIG. 2A, the optical interconnection block includes a plurality of optical connection rods 8 in parallel, each having a mirror 10 with the reflection angle of 45°. Vertical light beams 11 output from the light source of the transmitter or input to the photo-detector of the receiver are input to/output from the side 9 of the transmitter of the optical connection rod 8, and the light beams are reflected on the mirror 10 by the angle of 90°, and are then horizontally transmitted through the optical waveguide 2 of the optical PCB 1 of FIG. 1.
Referring to FIG. 2B, the optical interconnection block includes a plurality of parallel optical connection rods 8 bent by the angle of 90°. Vertical light beams 17 output from the light source of the transmitter or input to the photo-detector of the receiver are input to/output from the side 15 of the transmitter of an optical fiber 14, and the light beams are horizontally transmitted through the optical fiber 14 and are transmitted through the optical waveguide 2 of the optical PCB 1 of FIG. 1.
However, it is difficult to accurately match the position of the optical fiber 8 or 14 in the optical interconnection block with the position of the optical waveguide 2 of the optical PCB 1 since the optical interconnection blocks are connected with a single optical fiber for each optical signal channel. That is, it is difficult to control an optical path when the optical paths, in the order of the light source 5 of the transmitter←→the optical fibers 8 and 14 in the optical interconnection block ←→the optical waveguide 2 in the optical PCB ←→the optical fibers 8 and 14 ←→the photo-detector 6 of the receiver, cross each other and the light beams are provided to an adjacent channel.

Optical printed circuit board and optical interconnection block using optical fiber bundle

Information and Communication Univerity Research and Industrial Cooperation Group


An elastomeric vial cap used for sealing a vial container, but allowing pipette access to its containment fluid includes an annular flange portion for capping the vial and a sloped truncated cone portion to easily guide the pipette into the vial container. A tubular seal portion is configured to encircle the truncated cone portion and firmly engage an inside wall of the vial container with ease of insertion. A center flap portion is circumscribed by a channel at its top surface for penetration by the pipette and has a flex portion. The center flap portion separates around the perimeter of the channel but hinges at the channel above the flex portion and does not become dislodged. The ratio of the diameters of the pipette and the center flap portion is such that significant problems related to back-pressure and vacuum conditions do not exist during transfer of the containment fluid.

This invention relates to a cap for use with a fluid container. In particular, this invention relates to a cap that encloses a vial container of various volumes and shapes. The vial cap allows for penetration by pipette or sampling tube while avoiding the problems associated with the conventional vial cap discussed below.
A problem common to conventional vial caps is the propensity for the pipette or sampling tube to cause a back-pressure during filling or a vacuum condition during aspiration of the vial container. Back-pressure and vacuum conditions can cause errors in the precise transfer of fluid to or from the vial container. For example, a vacuum condition created in the vial container during a pipetting operation may cause the amount of fluid removed from the container to be less than the desired amount. Thus, problems transferring the precise amount of fluid from the vial container to the pipette or vice versa may occur when the pipette engages the vial cap and begins to add or withdraw containment fluid from the vial container.
Another problem with conventional vial caps is lack of symmetry and flange portions that overhang the vial container. Robotic manipulating arms are designed to grasp vial containers of a particular diameter or width. When conventional vial caps are utilized with vial containers, they oftentimes have flanges or other extremities that extend beyond the outer perimeter of the vial container and may cause the robotic manipulating arm to fail to grasp the vial container properly. These conventional vial caps may cause a transport or pipetting operation to completely fail.
Another problem of the conventional vial cap is that it may be damaged during a pipetting operation because the vial cap often has a shallow slope leading to a center flap portion of the vial cap. The shallow slope may cause the pipette to impinge on an area of the vial cap that is not penetrable rather than reaching the center flap portion.
Another problem may occur when the pipette penetrates the center flap portion. The center flap portion may tear-away and fall into the containment fluid causing pipetting and/or contamination problems.
What is needed is a vial cap that works well with robotic manipulating arms, maintains its operability during pipetting operations, keeps its center flap portion from falling into the containment fluid, and can facilitate the transfer of containment fluid without creating back-pressure or vacuum conditions that interfere with the proper pipetting of the containment fluid.


A method and apparatus route telecommunication calls in a telecommunication switching system by receiving visual information for a caller of one of the telecommunication calls; analyzing the received visual information for characteristics of the telecommunication calls; and routing the one of the telecommunication calls based on the analyzed visual information.

In the prior art, customer relation management systems (also referred to as call centers or automatic call distribution systems) receive incoming calls and route these calls to agents attached to the customer resource management system so that the agents can assist customers. Within the prior art, it is known for CRM systems to be quite large and have hundreds of agents that are connected to the CRM system. A CRM system may service a plurality of corporations with sets of agents being assigned to each corporation. This allows the agents to have experience with the needs of the customers of a particular corporation. In addition, it is known to have certain agents who are considered experts on a particular subject, and the less skilled agents can transfer customers to the more skilled agents for additional information.

Apparatus and method for routing telecommunication calls using visual caller information


A reflective plate comprises a substrate, a plurality of protrusions each formed on the substrate and having a curved surface, and a reflective film formed on the substrate having the protrusions, wherein a planar shape of each of the protrusions is indefinite, and when a frame line of the planar shape of each of the protrusions is divided into fine line segments, the line segments are pointed in all directions or in predetermined directions. This improves reflective properties such as dispersion properties.

These days, mobile information terminals, video recorders, and the like are being downsized and becoming more and more portable. This has presented a problem of how to reduce the power consumption of image display devices used in those terminals and recorders.
Image display devices capable of reducing power consumption include reflective type liquid crystal display devices and transflective type liquid crystal display devices.
Reflective type liquid crystal display devices display images by utilizing outside light such as sunlight and indoor lighting and controlling the amount of light reflected by a reflective plate. This makes a back light needless and realizes a reduction in power consumption. In addition, high visibility can be secured for the display screen even under strong outside light such as direct sunlight, and therefore, the display devices are often used in instruments for mobile phones.
Transflective type liquid crystal display devices display images by utilizing light both from outside and the back light. This enables it to turn off the back light when images are displayed in bright surroundings, and thus realizes a reduction in power consumption. Under strong outside light such as direct sunlight, high visibility can be especially secured by reflecting outside light. In dark surroundings, on the other hand, visibility can be secured by turning on the back light.
Reflective plates equipped in those two types of liquid crystal display devices are preferably without specularity. This is because if light is specular-reflected, a light source appears on a reflective plate and little light is reflected except in this place of appearance, making the display screen dark. In such a case, images are displayed brightly only when seen from the regularly reflected direction of light, and images are very dark when seen from other directions. That is to say, brightness can not be secured for displayed images except in the regularly reflected direction of light, and therefore, the display screen can not be viewed naturally. In view of this, it is indispensable for reflected light to be diffused.
There are mainly two methods to diffuse reflected light. 1) To form the surface of a reflective plate into fine protrusions and depressions.
2) To provide a diffusion film for light diffusion on the viewer's side of a liquid crystal display device.
In the method 1) among these methods, since reflective properties depend on protrusions and depressions on the surface of the reflective plate, the protrusions and depressions are extremely important elements to decide display properties of a liquid crystal display device.
However, even if a liquid crystal display device has a reflective plate with protrusions and depressions, there is a problem of a dark display screen in dark surroundings with extremely small outside light. Specifically, when outside light comes into the device, the light first passes through a liquid crystal layer in a liquid crystal cell. Then, the light is reflected by the surface of the reflective plate on the backside of the liquid crystal layer, and then passes through the liquid crystal layer again to be extracted as display light. That is to say, when outside light which has come inside the device goes out of the device, the amount of the light is decreased extremely. When the amount of outside light is inherently small, almost none of it is utilized as display light, thus making the display screen dark. Especially for a liquid crystal display device having a color filter to absorb light, the amount of light decreases considerably.
In view of this, for reflective type liquid crystal display devices, it is required to further increase the efficiency of light utilization. This is preferable also for transflective type liquid crystal display devices because power consumption is reduced.
One of methods to increase the efficiency of light utilization is to control the shape of a (diffusion) reflective plate so that incident light is reflected over an effective range. In SHARP TECHNICAL JOURNAL, vol. 74 (1999), on pages 41–45, there is disclosed an ideal distribution of tilt angles of protrusions provided on a reflective plate. FIG. 1 is a graph showing the relationship between tilt angles of protrusions and the presence probability of the tilt angles. A symbol (a) in the figure shows that there is almost no flat portions (where the tilt angle is 0 degrees) on the surface of the reflective plate, and protrusions having a tilt angle of up to about 8 degrees are provided on the surface. In addition, the presence probability of the protrusions increases up to 8 degrees, and no protrusions of more than 8 degrees of tilt angle exist. In such tilt angle distribution, light is designed to be reflected uniformly over a range of about 25 degrees from the regularly reflected direction, and the light is not dispersed outside the range.
The reflective properties of a reflective plate having the tilt angle distribution can be described as follows. FIG. 2 is a graph showing the relationship between an incident angle (degree) of incident light and the obtained gain. Gain is a value obtained such that the brightness of incident light with respect to an incident angle is divided by the brightness of the incident light with respect to a (diffusion) reflective plate. In the figure, reflective properties in the case of the ideal tilt angle distribution (corresponding to the symbol (a) in FIG. 1) are shown as a solid line (a). The viewer looks at the display screen mostly from the range of 25 degrees from the normal direction. Therefore, if brightness increases within this range, bright images are displayed, as in the case of the reflective properties shown as the solid line (a).
On the other hand, a dotted line (b) shows reflective properties in the case of a symbol (b) shown in FIG. 1, where tilt angle distribution is such that the presence probability of the protrusions peaks at 15 degrees of tilt angle. With such reflective properties, incident light angled by 50 degrees, for example, can be reflected towards the normal direction. In other words, incident light angled by various degrees is reflected to have widespread and almost uniform brightness. Therefore, such reflective properties provide high light diffusion properties. However, brightness towards the normal direction is lower than the solid line (a). Note that when tilt angle is 20 degrees for example, incident light is not released out of the display device.
In addition, a symbol (c) shown in FIG. 1 is the case where the peak of the presence probability of the protrusions is in the region of small tilt angles. In this case, regular reflection components increase and the reflective plate has specularity. Accordingly, obtained reflective properties are shown as a dotted line (c) in FIG. 2. Such reflective properties cause extremely large variations in brightness with respect to incident angles.
Thus, since the reflective properties of the reflective plate depend on the tilt angle distribution of the protrusions, it is important to control the tilt angle distribution of the protrusions in order to effectively utilize incident light.
There are various methods to produce a reflective plate, among which are to roughen the surface of a reflective metal film, and to pattern a resin layer to be protrusions and depressions by etching. When a resin layer is patterned to be protrusions and depressions, the use of a thermoplastic photo-resist makes it easy to form a uniform pattern. This is specified as follows. FIGS. 3A and 3B are cross sectional views illustrating the process of forming a protrusion. First, a photo resist layer is formed on a substrate 101 and exposed through a mask having a predetermined pattern, and then developed. By these steps, protrusions 102 each having a rectangle cross section are formed. Further, by heat-treatment, corner portions of each of the protrusions 102 are heat-fused, forming protrusions 103 each having a smoothly curved surface as shown in FIG. 3B. However, if there is a wide distance between the protrusions 103, a flat portion 104 is also formed. This provides specularity to the reflective properties of the obtained reflective plate.
In Japanese Unexamined Patent Application No. 6-27481A, there is disclosed a reflective plate that solves the problem of specularity. This publication discloses a reflective plate wherein wave-shaped picture element electrodes with their upper surfaces being continuous are formed on an insulative substrate. This reflective plate is fabricated as follows. A first polymeric resin layer is formed on the insulative substrate and patterned to form protrusions. Next, a second polymeric resin layer is formed over the insulative substrate having formed thereon the protrusions in order to fill gaps between the protrusions. Thereby, the second polymeric resin layer also becomes protrusion-depression shaped. However, the tilt angles of the second layer's protrusions are smaller than those of the protrusions of the first layer. In view of this, by reducing flat portions, regularly reflected light can be reduced. However, in the above-described method, since there is an extra step of coating the second polymeric resin layer and drying it, there arises a problem of increasing fabrication costs.
In order to solve the problem of increasing fabrication costs, the present inventors attempted a method to form a reflective plate having a protrusion-depression surface by forming protrusions without gaps using a single layer. Specifically, a photo-resist was coated on a substrate and light-exposed through a mask. A pattern of the mask was such that a gap between light shielding portions was set to be 5 μm or less. After the photo-resist was developed, protrusions each having a rectangle cross section were formed. Each gaps between the protrusions was 5 μm or less. Further, the rectangle protrusions were softened and deformed by heat treatment to fill the gaps therebetween. Among the gaps, gaps of 3 μm or less were filled up and adjacent protrusions bonded to each other, thus forming a flat portion. As a result, tilt angle distribution was different between a portion in which the protrusions were distant and a portion in which the protrusions bonded, causing non-uniform reflective properties on the same plane. As a result, there arose a problem that unevenness was recognized on the display screen. In addition, when a reflective layer made of Al, Ag, or the like is formed on a source electrode and a drain electrode, there is a danger of a shortcut between the source electrode and the reflective layer at a portion without a resist.
In addition, there is another method that the step of development is stopped halfway so that a part of a resist film (hereinafter referred to as a remaining film) remains between the protrusions of the resist. When this method is employed, since the protrusions originally form a continuous surface, a continuous protrusion-depression surface is formed by melting (heat-fusion). However, the amount of deformation during the melting step varies depending on the thickness of remaining films, and the amount of deformation decreases as the remaining films become thinner. Therefore, to control the tilt angles of the protrusions, it is required to precisely control the thickness of the remaining films. However, the developing speed of the resist film depends on many factors such as temperature, the ability of a developer, and how much the resist film is fatigued. This makes it difficult to stop the development halfway and have the same amount of remaining films to control the tilt angles.
Also in Japanese Patent No. 2698218, there is disclosed a method to form the protrusion-depression surface of the reflective plate. FIG. 4A is a plan view schematically showing a reflective plate disclosed in this publication. FIG. 4B is a cross section taken along the line A—A in FIG. 4A.
As shown in FIG. 4A, a multiplicity of protrusions 112 distant from one another are provided on a substrate 111, and a reflective film 113 is provided to cover the protrusions 112. By providing the protrusions 112, the reflective plate is provided with light dispersion properties, and the appearance of a light source on the display screen is reduced. However, in this prior art example, since the protrusions 112 are made distant from one another, gap portions 114 are flat. In addition, since the area of the gap portions 114 makes up much of the reflective plate as a whole, there is a peak for reflected light in the regularly reflected direction. As a result, a light source appears on the display screen, causing a problem of making the display screen dark.
In view of this, a reflective plate that has resolved this problem is disclosed in Japanese Patent No. 2756206. FIG. 5A is a plan view schematically showing the reflective plate disclosed in this publication. FIG. 5B is a cross sectional view taken along the line B—B in FIG. 5A. According to this publication, there are protrusions and depressions. A first film 122 having protrusions is provided on a substrate 121. To cover the first film 122, a second film 123 is formed. On the second film 123 is formed a reflective film 124. In such a configuration, the formation of the second film 123 smoothes the surface of the first film 122 and flat gap portions 125, realizing a smoothly curved surface in a protrusion-depression manner. This results in removal of flat portions that were considered as a problem in the foregoing example and realizes preferable light dispersion properties without a sharp peak in the regularly reflected direction.
However, in the latter prior art example, in the formation of the reflective plate, the step to form the first film 122 having the protrusions on the substrate 121, and the step to form the second film 123 by coating liquid over the first film 122 and hardening the liquid were required. That is to say, two steps were required to form the protrusion-depression shape, which was redundant.

Reflective plate and display device using the plate

Matsushita Electric Industrial Co., Ltd.