A method for determining the characteristic properties of soot particles originating from combustion processes utilizes the determination of the blackening of a filter paper. In order to allow for achieving a quick and relatively accurate determination of the particle sizes, possibly of further characteristics as well, a method of this kind provides that the pressure conditions on the filter paper are established as well. It is advantageous for this purpose to determine the differential pressure on the filter and/or filter paper caused by the deposition of the particles.

1. Field of the Invention
The invention relates to a method for determining the characteristic properties of soot particles from combustion processes by way of determining the blackening of a filter paper.
2. The Prior Art
Smoke meters of the current generation establish the filter smoke number (FSN) or the soot emission in mg/m3 by means of the deposition of particles on a filter paper. Due to the possibility of varying the suction length and suction time, it is possible to vary the measuring range in the context of such a method within very wide limits. The measured values range approximately from FSN 0.001 to 10, which corresponds to measured concentration values of approximately 0.015 to 30000 mg/m3.
But measuring the size of the emitted particles is, on the one hand, either quite time-consuming or quite complex and, on the other hand, in part very expensive equipment is necessary for the process. Examples of equipment of this kind include impactors, however, they have the disadvantage of long measuring times and the requirement of having to weigh the collected particles; electrical low pressure impactors (ELPI), a low-pressure impactor type with dynamic measurement; and particle mobility analyzers such as scanning mobility particle sizers (SMPS) or double differential mobility particle sizers (DDMPS), etc.
Currently, the composition of the particles can only be established either by way of chemical extraction—with diverse solvents, such as dichloromethane—or by way of thermogravimetric methods, which means by way of sample heating. To this end, the particles must be collected in a defined filter, weighed and submitted for analysis according to one of the methods referred to above—including weighing of the filters following the filter treatment.
The object of the present invention therefore consists in providing a method that allows for the simple, quick and relatively accurate determination of the particle sizes and possibly of further characteristics as well.

Method for determining the characteristic properties of soot particles


Cosmetic compositions and methods, particularly for skin lightening, using compound and derivatives of general formula I and/or II as skin lightening agents alone or in combination with other skin benefit agents and together with a cosmetic vehicle:

Many people are concerned with the degree of pigmentation of their skin. For example, people with age spots or freckles may wish such pigmented spots to be less pronounced. Others may wish to reduce the skin darkening caused by exposure to sunlight or to lighten their natural skin color. To meet this need, many attempts have been made to develop products that reduce the pigment production in the melanocytes. However, the substances identified thus far tend to have either low efficacy or undesirable side effects, such as, for example, toxicity or skin irritation. Therefore, there is a continuing need for new cosmetic skin lightening agents, with improved overall effectiveness.
Applicants have now discovered that 4-hydroxyphenylpyruvate and derivative compounds deliver skin lightening benefits. The general chemical formulas and structures of these compounds are discussed in more detail herein below. The 4-hydroxyphenylpyruvate and derivative compounds have been found to be cosmetically effective and possibly less irritating to the skin. These compounds of the present invention have not been used in cosmetics, nor have they been used, specifically, for lightening skin. The 4-hydroxyphenylpyruvate is available from Sigma-Aldrich.

Skin lightening agents, compositions and methods

Abstract: Where each R, independently, represents a hydrogen atom, C1–C4 acyl group, or C1–C4 alkyl group. Preferably, the compound is 4-hydroxyphenylpyruvate, i.e., where each R in the formula I is Hydrogen.


A method and apparatus for waking up a computer system using a peripheral device connected to a standard parallel port of the computer system. Functionality is added to the parallel port Select line normally used to indicate that the peripheral device connected to the parallel port is on line when the select signal is high. A signal transition on the Select line from low to high is detected and used to wake up the computer system. This toggling of the Selected line is detected and used to activate the computer system power supply into a normal operating state from a power save state.

1. Field of the Invention
This invention relates to computer systems and more specifically to powering up a computer system from a peripheral device connected to a standard parallel port of the computer system.
2. Description of the Prior Art
Personal computers, e.g. portable and desk top computers, often include a power management function. When the computer is inactive (not executing an application program or otherwise in use) the computer is placed in a standby mode. In the standby mode, typically only the memory is powered and a power management logic chip or chips are powered up. When the computer needs to resume operation due to keyboard input or other activity, the power management logic circuitry activates the power supply and powers up other portions of the computer including for instance the CPU (central processing unit).
However this presents the problem that devices such as Multi-Functional Peripherals (such as a combination facsimile machine-printer) connected to a parallel port of the computer may require the attention of the CPU when the CPU is powered down. For instance, if a facsimile is received by the facsimile machine, it must be stored into the computer's disk drive. If the computer is in the standby mode, the facsimile machine-printer connected to the parallel port needs a way to wake up (power up) the CPU of the computer and the disk drive which are powered down in the standby mode. However, no such feature is now available. It is also important that this wake up be performed quickly and be implemented in inexpensive fashion to make it suitable for use with a variety of computers.

Method and apparatus for waking up a computer system via a parallel port


The heat exchanger of the present invention has a charge air cooler stacked upstream of a jacket water cooler. The charge air cooler is split into two sections. Each section has a vertical tank and header on the outside of the charge air cooler. Charge air enters the respective tanks and then horizontally flows to a vertical center tank, where it flows vertically to the outlet, and is routed to the engine. Maximum entering temperature differentials in the charge air cooler occurs at the sides of the cooler, as does maximum heat energy transfer. The air passing through the middle of the charge air cooler (adjacent the vertical center tank) gains the least amount of heat energy. The jacket water cooler can be a vertical flow cooler. A significant portion of the jacket water cooler at the middle of the jacket water cooler operates at increased entering temperature differential.

1. Field of the Invention
The present invention relates to a heat exchanger, and particularly to a series or stacked heat exchanger with a horizontally flowing charge air cooler and a vertically flowing jacket water cooler.
2. Description of the Related Art
It is well known that heat energy contained in one fluid is capable of being transferred to another fluid. Such heat transfer is described in the classical heat transfer equation: Q=UAdT. In this equation, Q represents the heat transfer, U represents a coefficient of heat transfer, A represents the surface area through which the heat can be transferred, and dT represents the change in temperatures between the two mediums. Heat exchangers, and radiators in particular, are designed for a relative high level of transfer of heat energy from one medium to another. One common example is an automobile radiator, in which a coolant fluid passes through an engine to absorb heat energy from the engine. The coolant fluid then is routed through the radiator, where heat is transferred from the coolant fluid to the environment (ambient air).
Engineers and designers have incorporated many strategies to increase the amount of heat that a heat exchanger is capable of transferring. One strategy is to attempt to increase the coefficient of heat transfer. Design components, such as the incorporation of louvers, dimples, waves, ridges and other alterations to the fin and tube profiles have been effectively used. While these improvements are quantifiable and generally useful, there are limitations (both practical and theoretical) as to how much the coefficient of heat transfer can be improved. For example, the increased capital investment in equipment and tooling costs may overshadow any savings associated with the increased coefficient. Accordingly, it may take a long time to recapture those costs through efficiency savings, if it is even possible at all.
Others have had success in increasing the heat transferring capability of the heat exchanger by increasing the surface area between the two mediums (i.e. increasing the size of the heat exchanger). The increases in surface area can come from a combination of increases in height, width, depth and density of the heat exchanger. Often times, the size requirements for shipping, packaging and deliverable use dictate maximum dimensions in the height and width dimensions. In such situations, the only remaining variable is the depth of the unit. Accordingly, designers have increased the depth of the heat exchanger in order to increase the surface area.
Some heat exchangers are designed for use with engines having turbochargers. It is standard practice to stack two or more radiators in series to cool both a jacket water coolant from the engine and charge air compressed by one or more turbochargers. The traditional configuration has a charge air cooler first, and a jacket water cooler second. Put another way, the charge air cooler is upstream of the jacket water cooler in some configurations, such that air first passes through the charge air cooler and second through the jacket water cooler. There are several drawbacks associated with the standard configuration.
It is well known that the maximum heat transfer in a charge air cooler occurs at the inlet side of the cooler where a maximum entering temperature differential exists between the fluids exchanging heat energy. The heat transfer decreases as the charge air passes through the cooler, as the temperature difference between the ambient air and the charge air decreases. The result is that the air (having passed through the charge air cooler) has an uneven temperature distribution as it passes through the jacket water cooler (the second cooler).
In a configuration where the charge air cooler has charge air moving up vertically through the cooler, the effective area of the jacket water cooler can decrease. This is because the air that passes through the charge air cooler near the inlet realizes the largest heat rise. The air with the largest heat rise can have a temperature that approaches or even surpasses the engine coolant temperature in the jacket water cooler. With little or no temperature differential in those areas of the jacket water cooler, no cooling takes place. The jacket water cooler can therefore operate at less than desired efficiency. To compensate for and overcome this inefficiency, air movers with increased horsepower capacity are utilized to move additional air through the heat exchanger. Yet, this approach can prove ineffective where little or no temperature differential exists. The standard configuration is therefore designed to be less than fully efficient.
A considerable amount of pressure, caused by the expansion of the air as it gains energy from the heat exchanger, can develop near the inlet sides of the coolers. This pressure gain can negatively affect the flow characteristics of the air passing through the coolers. The fan therefore needs to have greater horsepower capacity (i.e. higher initial cost plus increased energy consumption during operation) in order to move the intended amount of air through the heat exchanger at the desired locations to overcome the increase in external system pressure.
A further issue facing charge air coolers is the potential for axial thermal expansion of the tubes within the charge air cooler, which leads to local stress and high vibrations risk because of the different growth characteristics of the components of the heat exchanger.
A still further potential drawback associated with standard charge air coolers is that the inlet tube and header interfaces are subject to a great deal of stress. The weight of the charge air and the vibrations can exacerbate the stress at the joints.
Thus there exists a need for a heat exchanger that solves these and other problems.

Heat exchanger with horizontal flowing charge air cooler


The invention relates to a non-volatile memory with floating gate, in particular a Flash-EPROM, in which writing takes place through injection of hot electrons into the floating gate and in which erasing takes place through injection of hot holes. To keep the write and erase voltages sufficiently low, p-type zones which locally increase the background doping concentration of the p-type substrate are provided around the n-type source and drain zones. These p-type zones cause an increased field strength at the drain zone whereby hot electrons are formed at the pinch-off point also at lower voltages. This increased background concentration in addition reduces the breakdown voltage of the pn junction of the source and drain zones, so that hot holes for erasing can be formed by pn breakdown at comparatively low voltages. The device is particularly suitable for being integrated into a signal processing IC manufactured in a standard process, such as a microcontroller.

The invention relates to a semiconductor device with a semiconductor body which is provided at a surface with a non-volatile electrically erasable memory comprising a number of memory elements with source and drain zones situated in a p-type surface region of the semiconductor body, adjoining the surface, and mutually separated by an interposed channel region, with a floating gate situated above the channel region and insulated therefrom by an interposed gate dielectric, and with a control gate insulated from the floating gate, information being written and erased through injection of hot electrons and hot holes into the floating gate, while the hot electrons are generated in the channel adjacent the drain zone through induction of a channel current between the source zone and drain zone. The invention also relates to a method of manufacturing this semiconductor device.
Such a device is known, for example, from European Patent Application EP-A 0 218 342, publication date 15.04.87.
Non-volatile memories with floating gates are known in the literature, for example, under the abbreviations EPROM and EEPROM (Electrically Erasable Programmable Read-Only Memory). An embodiment which is particularly popular at the moment is known under the name Flash-EEPROM or Flash-EPROM, with which a very high density can be obtained because each memory cell is formed by a single floating-gate transistor. The selection transistors, which are necessary for each memory element in an EEPROM of a usual type, are absent in the memory.
In the known device mentioned above, the transistor selected for writing is brought into the "ON state" by means of a high voltage applied to the control gate and the drain zone. Owing to the strong electric field near the drain zone, high-energy (hot) electrons are formed in the channel current with sufficient energy for flowing across the potential barrier of the gate dielectric to the floating gate, partly also under the influence of the electric field in the gate dielectric. Erasing of the information takes place in the known device through injection of hot holes which compensate the charge injected during writing.
This method differs from the usual method of erasing whereby electrons tunnel from the floating gate to a zone in the semiconductor body, for example, the source zone. A very thin dielectric is necessary in view of the tunnelling effect, which implies an added complication for the manufacturing process of the device, especially when the memory is embedded in a signal-processing IC, for example, a microcontroller which is manufactured by a different process. Such a thin tunnel oxide is unnecessary when erasion takes place with hot holes. The hot holes are formed by a "snap-back" method in which a comparatively high voltage is applied between the source zone (earth) and the drain zone (7 V), while the transistor is in the "OFF state". The control gate is then brought to a high voltage (13 V) for a short period whereby the transistor enters the "ON state", after which the voltage at the control gate is reduced to 0 V. Since the pn junction of the source zone remains forward-biased, an electron current is injected into the substrate so that a comparatively high drain current is maintained owing to lateral npn operation in spite of the low voltage at the control gate. Thanks to the low voltage at the control gate, hot holes formed by the strong field can be injected into the floating gate.
A disadvantage of the known device is that the "snap-back" mechanism described here is highly critical. Thus, the optimum voltage at the drain zone, which must be sufficient for obtaining the snap-back effect but must be lower than the breakdown voltage between the source and drain zone (punch-through voltage), strongly depends on doping concentrations and dimensions. Owing to the spread in such parameters, it is often difficult in practice to choose for the device such an adjustment that all cells can be erased in the manner described above.
During writing, a high voltage is applied to the selected word line in order to render the transistor in the selected cell conducting. Owing to capacitive coupling, the floating gates of the other cells connected to this word line may get a higher potential. It is possible then for electrons to flow towards the floating gates of these quasi-selected cells owing to the tunnelling effect. This phenomenon, which is known as "gate disturb", was described inter alia in the publication "Degradations due to hole trapping in flash memory cells" by Haddad et al. in IEEE Electron Device Letters, vol. 10, no. 3 March 1989, pp. 117-119. As is indicated in this publication, the "gate disturb" effect is reinforced by holes which are trapped in the gate dielectric. In a selected cell, moreover, it is found that writing becomes more difficult after a number of write/erase cycles in the sense that the difference between the threshold voltage in the programmed state and the threshold voltage in the non-programmed state becomes smaller. A possible explanation for this is that the electric field in the channel is weakened by the trapped holes in the gate oxide. Since the tunnelling effect is also strongly influenced by the electric field across the gate oxide, it is important to keep the programming voltage as low as possible, especially in memories in which erasing takes place with hot holes. Moreover, high voltages in general impose additional requirements, for example, on the dielectric insulation, parasitic channel formation, etc, which seriously hamper the embedding of the memory in an integrated circuit manufactured by a standard CMOS logic process. This also renders it desirable to keep the programming voltages and erasing voltages as low as possible.

Semiconductor device having a non-volatile memory and method of manufacturing such a semiconductor device


A method, apparatus and code product for estimating labor costs associated with producing a printed circuit board assembly.

Software solutions in the marketplace for estimating the manufacturing labor portion of printed circuit board assembly manufacturing currently focus on the cost of materials, which average 80-85% of the total cost of the product. The remaining 15-20% of the cost is the labor portion associated with manufacturing, testing and other items required to convert the product from a collection of raw materials to a printed circuit board assembly.
Because no commercial solutions exist for analyzing the labor component of the manufacture of printed circuit board assemblies, the labor component of the overall cost of a printed circuit board assembly is analyzed by:                Comparing the quotation on a particular printed circuit board assembly to a similar assembly previously manufactured by the same supplier,        Experience in the manufacturing process and understanding the labor steps associated with the particular product and/or        No analysis; simply accepting the conversion cost (cost of labor) provided by the supplier.
The present invention eliminates the need for comparison, extensive manufacturing expertise and/or heavy dependence on the information provided by the supplier. The present invention, otherwise known as the Manufacturing Labor Cost Estimator, is a first of a kind software tool specifically targeted at the analysis of labor costs of manufacturing printed circuit board assemblies. It is difficult to quantify the cost savings associated with the use of Manufacturing Labor Cost Estimator as past labor costs have been negotiated using empirical data and educated hypothesis.


A circuit module includes one or a plurality of semiconductor parts, a substrate having the semiconductor parts mounted thereon, and terminals arranged on an outer periphery of the substrate along a plurality of sides of said substrate. The circuit module is connected to a board of a computer by plugging the terminals into corresponding terminal holes, so that the terminals are used in common for providing electrical connection and mechanical connection with the board of the computer.

The present invention generally relates to circuit modules having electric circuits in a form of a module.
Conventionally, electric circuits are provided on a circuit board, and a computer board manufactured by Micromint is an example of such a circuit board. This computer board has a group of terminals provided along only one side of the computer board. For this reason, there is a problem in that the size of the computer board is approximately 330 mm.times.120 mm which is relatively large.
Another example of such a circuit board has extended memories of a computer on a circuit board. This extended memory board has a group of terminals provided along only one side of the extended memory board, and the size thereof is large.
FIGS. 1 and 2 show an example of a conventional a computer board 10 manufactured by Micromint. In FIGS. 1 and 2, the computer board 10 has mounted thereon a central processing unit (CPU) 11, a first POACH (PC On A Chip, trademark) 12 manufactured by Zymos, a second POACH 13, third POACHs 14 and 15, a basic input output system read only memories (BIOS-ROMs) 16 and 17, a memory 18 made up of eighteen 256 kbit dynamic random access memories (DRAMs) 19, a bipolar programmable read only memory (PROM) 20, a delay line 21, an integrated circuit group 22 for producing access timings, for example, a calendar circuit part 23, and a keyboard controller 24. All of these elements of the computer board 10 are mounted on only a top surface of a board 25. A terminal group 26 is provided along one side of the board 25.
The POACHs 12 through 15 are integrated circuits (ICs). For example, the POACHs 12 and 13 are peripheral controller chips, the POACH 14 is an address buffer chip, and the POACH 15 is a data buffer chip.
The computer board 10 is assembled into a computer (not shown) by plugging in the terminal group 26 to a connector (not shown) and inserting the computer board 10 in an upright position.
FIGS. 3 and 4 show the first POACH 12. The first POACH 12 has a stage 100, a plurality of leads 101, a semiconductor chip 102, a plurality of wires bonded to connect chip 102 and the leads 101, and a synthetic resin-formed package portion 104. Each lead 101 has a shape such that the inner end thereof is narrow and the outer end thereof is wide. A length L.sub.2 of each lead 101 is about 8 mm which is approximately four times a length L.sub.1 of the wire 103 which is about 2 mm. For this reason, the size of the first POACH 12 is 29 mm.times.29 mm which is relatively large. A thickness t.sub.1 of the first POACH 12 is 3.9 mm.

Shielded circuit module with terminal pins arrayed on four sides for connection to a computer board


This invention relates to printed circuit boards having improved fire resistance and improved environmental stability. The invention provides halogen-free fire retardant printed circuit boards incorporating potentially flammable polymers. Flame resistant thermoplastic layers prevent combustion of thermosetting polymers, as well as adding strength to the laminate, resulting in a less brittle thin core than the prior art. The flame resistant circuit board is cost efficient, environmentally safe and has excellent properties, including a decreased probability of shorting, good dielectric breakdown voltage, a smooth surface and good electrical/thermal performance.

1. Field of the Invention
This invention relates to printed circuit boards having improved fire resistance and improved environmental stability. More particularly, the invention relates to halogen-free fire retardant printed circuit boards incorporating potentially flammable polymers.
2. Description of the Related Art
Printed circuit boards are employed in a wide variety of applications. For example, they can be found inside radio and television sets, telephone systems, automobile dashboards and computers. They also play an important role in the operation of airborne electronic equipment and guided missiles. In forming insulating dielectric materials for printed circuit boards, it is common to employ organic polymer films that may be flammable under certain circumstances.
To combat this problem, fire retardant halogen additives are commonly employed. The purpose of the halogens is to attain an acceptable flammability rating as determined by Underwriters Laboratory (UL) 94V0 or 94V1 flammability tests, for most standard resins. For example, Japanese abstract JP6240214 provides a copper-clad laminate having a copper foil coated with a flame-retardant adhesive. The flame-retardant adhesive comprises a poly(vinyl acetal) resin, epoxy resin, polyisocyanate resin, and brominated polyester resin. U.S. Pat. No. 6,071,836 discloses polybutadiene and polyisoprene thermosetting compositions having a bromine-containing fire retardant. However, these additives are very expensive and interfere with the physical and electrical properties of the polymer. Also, decomposition of dielectric materials having halogen additives produces carcinogenic materials such as furan and dioxins.
In order to minimize the impact on the environment of electronic materials, many countries are requiring the substrates used in circuit boards to be halogen-free. For example, Japanese abstract JP11343398 provides a laminate and metal foil utilizing a flame retardant epoxy resin composition. This flame retardant composition comprises an epoxy resin, a hardener and an additive, wherein at least one incorporated hardener comprises a polycondensate of phenols, a compound having a triazine ring and aldehydes, and an inorganic filler as an additive. Also, Japanese abstract JP10195178 discloses a halogen-free flame-retardant composition comprising a bisphenol A epoxy resin, a novolac epoxy resin, a phenolic resin curing agent, a cure accelerator and an inorganic filler. U.S. Pat. No. 5,082,727 teaches a flameproof product wherein the flameproofing agents are a combination of organic borates, salts of phosphoric acids and oxide hydrates of magnesium and/or of aluminum. However, these alternatives are also very expensive and do not have good peel strengths to foil conductors.
It has therefore been desirable to provide an affordable, non-flammable, halogen-free dielectric composition for printed circuit boards having good properties and performance. The present invention offers a solution to this problem, providing a method by which copper foils are coated with non-halogenated thermoplastic dielectric layers and thermosetting polymer layers.
In particular, a printed circuit board is provided comprising a substrate having opposite surfaces, a thermosetting polymer layer on each of the opposite substrate surfaces, a thermoplastic dielectric layer on each of the thermosetting polymer layers, and an electrically conductive layer on each of the thermoplastic dielectric layers. The thermosetting layers may have various degrees of flammability, but the thermoplastic layers are inherently flame resistant and prevent combustion of the thermosetting polymers. The thermoplastic dielectric also adds strength to the laminate, resulting in a less brittle thin core than the prior art. The result is a cost efficient, environmentally safe and flame resistant laminate having excellent properties, including a decreased probability of shorting, good dielectric breakdown voltage, a smooth surface and good electrical/thermal performance.
The invention provides a circuit board comprising in order:
a) a planar substrate having opposite surfaces;
b) a thermosetting polymer layer on each of the opposite substrate surfaces;
c) a thermoplastic dielectric layer on each of the thermosetting polymer layers; and
d) an electrically conductive layer on each of the thermoplastic dielectric layers.
The invention also provides a process for manufacturing a printed circuit board comprising:
a) depositing a thermosetting polymer layer onto opposite surfaces of a substrate;
b) depositing a thermoplastic dielectric layer onto each of the thermosetting polymer layers; and
c) depositing an electrically conductive layer onto each of the thermoplastic dielectric layers.
The invention provides a halogen-free, fire retardant printed circuit board.
The first step in the process of the invention is to deposit a thermosetting polymer layer onto opposite surfaces of a planar substrate. Typical substrates are those suitable to be processed into an integrated circuit or other microelectronic device. Suitable substrates for the present invention non-exclusively include non-halogenated materials such as fiberglass, aramid (Kevlar), aramid paper (Thermount), polybenzoxolate paper or combinations thereof. Of these, fiberglass is the most preferred substrate. Also suitable are semiconductor materials such as gallium arsenide (GaAs), silicon and compositions containing silicon such as crystalline silicon, polysilicon, amorphous silicon, epitaxial silicon, and silicon dioxide (SiO2) and mixtures thereof. The preferred thickness of the substrate is of from about 10 to about 200 microns, more preferably from about 10 to about 100 microns. In a preferred embodiment of this invention, the substrate of the printed circuit board may comprise a plurality of adjacent strata including the strata of the above substrate materials, forming a complex multilayered article. In this embodiment, each stratum is attached to an adjacent stratum by a thermosetting polymer layer.
The thermosetting polymer layers are preferably deposited onto the substrate as liquids by coating, evaporation or vapor deposition to allow for control and uniformity of the polymer thickness. The liquid layers may subsequently be partially or fully cured on the substrate, thus forming a prepreg. For the purposes of this invention, an A-staged prepreg comprises a substrate having uncured thermosetting polymer thereon, a B-staged prepreg incorporates a partially cured thermosetting polymer, and a C-staged prepreg has a fully cured polymer. The most preferred prepreg for use in this invention is a B-staged, partially cured prepreg. Curing is conducted by placing the prepreg into an oven to evaporate any solvent from the polymer and either partially or fully cure the layers. Such may be done by subjecting the prepreg to a temperature of from about 100xc2x0 F. to about 600xc2x0 F., for about 1 to about 10 minutes. After curing is completed, the prepreg is removed from the oven and cooled.
The thermosetting polymer layers may also be deposited in the form of liquids or sheets that are laminated onto opposite sides of the substrate. Lamination is preferably conducted in a press at a minimum of about 275xc2x0 C., for about 30 minutes. Preferably, the press is under a vacuum of at least 28 inches of mercury, and maintained at a pressure of about 150 psi. The thermosetting polymer layers preferably comprise non-halogenated materials such as epoxies, bis-malimide triazine epoxies, thermosetting polyimides, cyanate esters, allylated polyphenylene ethers, benzocyclobutenes, phenolics and combinations thereof. Of these epoxies and polyimides are preferred. Preferably, the thermosetting polymer layers have a thickness of from about 5 to about 200 microns, more preferably from about 2 to about 100 microns.
Next, thermoplastic dielectric layers are deposited onto each of the thermosetting polymer layers or onto the conductive layers. The thermoplastic dielectric layers may be deposited in the form of liquids or sheets that are laminated onto each thermosetting polymer layer, under conditions similar to those for lamination of the thermosetting layers. Preferably, the thermoplastic dielectric layers are deposited onto the thermosetting layers as liquids by coating, evaporation or vapor deposition, allowing for control and uniformity of the polymer thickness. The thermoplastic dielectric layers preferably comprise a substantially non-flammable material as determined by the UL94V0 test. These materials preferably include polyimides, polyesters, polyester containing co-polymers, polyarylene ethers, liquid crystal polymers, polyphenylene ethers, amines, and combinations thereof. Of these, polyimides are the most preferred. Polyimides are preferred because they have high electrical strengths, good insulating properties, a high softening point and are inert to many chemicals. Preferred are polyimides having a glass transition temperature (Tg) of from about 160xc2x0 C. to about 320xc2x0 C., with a glass transition temperature of from about 190xc2x0 C. to about 270xc2x0 C. being preferred. Preferably, the thermoplastic dielectric layers have a thickness of from about 5 to about 200 microns, more preferably from about 2 to about 100 microns.
The thermoplastic dielectric liquids will typically have a viscosity ranging from about 5,000 to about 35,000 centipoise with a preferred viscosity in the range of 15,000 to 27,000 centipoise. The polymer liquids will each comprise a solution including from about 10 to about 60% and preferably 15 to 30 wt % polymer with the remaining portion of the solution comprising one or more solvents. It is preferred that a single solvent be used in each polymer solution. Useful solvents include acetone, methyl-ethyl ketone, N-methyl pyrrolidone, and mixtures thereof. A most preferred single solvent is N-methyl pyrrolidone.
Either one or both of the thermosetting and thermoplastic polymers may also optionally comprise a filler material. Preferred fillers non-exclusively include ceramics, boron nitride, silica, barium titanate, strontium titanate, barium strontium titanate, quartz, glass beads (micro-spheres), aluminum oxide, nonceramic fillers and combinations thereof. If incorporated, a filler is preferably present in the thermoplastic dielectric polymer or thermosetting polymer in an amount of from about 5% to about 80% by weight of the each polymer, more preferably from about 10% to about 50% by weight of the each polymer. The percent of total polymer to the substrate material and to fillers may have a strong effect on flammability of the circuit board. Generally, the less the amount of thermosetting polymer present in the circuit board, the less flammable the circuit board will be.
The ratio of the thermoplastic dielectric to the thermosetting dielectric is important to obtain a fire resistant circuit board having good properties. Preferably, the weight ratio of the thermoplastic dielectric to the thermosetting dielectric is from about 1:0.5 to about 1:15, and more preferably from about 1:1 to about 1:8.
After the thermoplastic dielectric layers have been deposited onto the thermosetting polymer layers and/or the electrically conductive layers the materials are laminated together to form a metallic clad substrate. Each conductive layer may comprise either the same metal or may comprise different metals. The conductive layers preferably comprise foils and preferably comprise a material such as copper, zinc, brass, chrome, nickel, aluminum, stainless steel, iron, gold, silver, titanium and combinations and alloys thereof. Most preferably, the conductive layers comprise a copper foil. At least one of the electrically conductive foils may also comprise a part of an electrical circuit.
The conductive layers preferably have a thickness of from about 0.5 to about 200 microns, more preferably from about 9 to about 70 microns. The conductive materials used in the flexible composites of this invention may be manufactured with a shiny side surface and a matte surface. Examples of such conductive materials are disclosed in U.S. Pat. No. 5,679,230, which is incorporated herein by reference. The conductive layers may be applied using any well known method of metal deposition such as electrolytic or electroless deposition, coating, sputtering, evaporation or by lamination onto the thermoplastic layer.
After the circuit board is formed, it may then be selectively etched using well known photolithographic techniques using a photoresist composition. First, a photoresist is deposited directly onto the conductive layer. The photoresist composition may be positive working or negative working and is generally commercially available. Suitable positive working photoresists are well known in the art and may comprise an o-quinone diazide radiation sensitizer. The oquinone diazide sensitizers include the o-quinone-4-or-5-sulfonyl-diazides disclosed in U.S. Pat. Nos. 2,797,213; 3,106,465; 3,148,983; 3,130,047; 3,201,329; 3,785,825; and 3,802,885. When o-quinone diazides are used, preferred binding resins include a water insoluble, aqueous alkaline soluble or swellable binding resin, which is preferably a novolac. Suitable positive photodielectric resins may be obtained commercially, for example, under the trade name of AZ-P4620 from Clariant Corporation of Somerville, N.J. as well as Shipley I-line photoresist. Negative photoresists are also widely commercially available.
The photoresist is then imagewise exposed to actinic radiation such as light in the visible, ultraviolet or infrared regions of the spectrum through a mask, or scanned by an electron beam, ion or neutron beam or X-ray radiation. Actinic radiation may be in the form of incoherent light or coherent light, for example, light from a laser. The photoresist is then imagewise developed using a suitable solvent. Subsequently, the conductive layer is etched by well known etching techniques. The circuit board may then be rinsed and dried. After the circuit lines and spaces are etched through the metal layer and the conductive layer, the remaining photoresist may be removed from the metal layer surface either by stripping with a suitable solvent or by ashing by well known ashing techniques.
It is preferred that each of the substrate, thermosetting polymer layers, thermoplastic dielectric layers and electrically conductive layers are absent, i.e. free of halogen containing fire retardant additives. More particularly, it is preferred that each of these constituents are absent, i.e. free of bromine containing fire retardant additives. As a result, the fire resistant printed circuits formed by this invention are more environmentally safe than those of the prior art.

Manufacturing fire retardant circuit boards without the use of fire retardant resin additives


A rubber cylinder sleeve for web-fed rotary offset printing machines has a covering layer which is a finite layer having a joint location, the joint location being filled with a compressible material.

1. Field of the Invention
The invention relates to a rubber sleeve having an inner carrier sleeve which can be expanded by means of air, at least one compressible layer arranged over the carrier sleeve, and an outer covering layer. A similar device is disclosed in U.S. Pat. No. 6,148,725.
2. Description of the Related Art
Sleeves of this type are disclosed, for example, by U.S. Pat. Nos. 5,429,048, 5,323,702, 5,440,981 and 5,304,267. One disadvantage of these known rubber cylinder sleeves (transfer cylinder sleeves) is that the middle and lower layers of the same have to be at least partly continuous. This has a particularly detrimental effect on the production costs.
In addition, U.S. Pat. No. 5,351,615 discloses the practice of applying a rubber blanket to a carrier plate, for example by adhesive bonding. After this, this arrangement is shaped into a rubber cylinder sleeve and the mutually facing ends of the carrier plate and those of the rubber blanket or rubber covering are joined to each other, for example by welding or adhesive bonding. Although this arrangement no longer has a gap, a joining seam or a joint location remains on the surface.
In the rubber cylinder sleeve shown in U.S. Pat. No. 5,429,048, its outer layer is continuously sleeve-like and consists of an incompressible material. Apart from the higher production costs already mentioned, a continuous outer layer has the disadvantage that, during rolling contact with a plate cylinder and an impression cylinder, the rubber blanket sleeve is loaded with tangential forces to which further forces are added with each revolution. High loading on the rubber blanket sleeve is established. This loading also has a detrimental effect on the printing quality (for example by a tendency to slippage of the rubber blanket sleeve in relation to the web to be printed. in the press nip, and in the rolling nip with a plate cylinder).
It is an object of the present invention to produce a genus-forming rubber cylinder sleeve, especially for web-fed rotary offset printing machines, more cheaply as compared with the known sleeves of this type, with approximately the same or improved printing quality and behaviour.
The object is achieved by designing the covering layer as a finite layer having a joint location which is filled with a compressible material. The rubber cylinder sleeve can be produced cost-effectively. In addition, it makes possible good printing quality since the joint location filled with compressible material is permitted to dissipate tangential forces during rolling contact with other printing-unit cylinders.
As is known from the prior art described above, the fundamental construction of such rubber cylinder sleeves substantially comprises an inner, preferably metallic sleeve. However, a glass-fibre reinforced (GRP) sleeve can also be used advantageously instead of the inner metal sleeve. The thickness of these sleeves is, for example, dimensioned in such a way that, when they are pushed onto the transfer cylinder, which is usually referred to as a rubber-covered cylinder, in printing machines operating in accordance with indirect printing processes, they can be expanded slightly by means of air. As shown in U.S. Pat. No. 5,429,048, such a sleeve can be pushed through the side wall of a printing machine onto the transfer cylinder previously exposed on one side. In the process, the sleeve to be pushed on is expanded with compressed air with the aid of openings provided in the transfer cylinder, so that fitting in a straightforward way is possible, after which, after the compressed air has been removed, the sleeve pushed on assumes a firm seat on the transfer cylinder.
At least one further layer which is compressible, i.e. having air inclusions, is appliedxe2x80x94directly or indirectlyxe2x80x94to this inner, preferably metallic carrier sleeve. At least one covering layer which, for example, can consist of an elastomeric material, is provided above this compressible layer. Using this material, the image to be printed is accepted from a printing plate, for example an offset printing plate or a sleeve-like offset printing plate, and is transferred to a printing medium.
A further non-expandable layer is preferably provided between the compressible layer (e.g. an elastomer with air inclusions) and the covering layer, for example in the form of a hard elastomeric material or, for example, in the form of short fibres (e.g. threads) which can also be embedded in the hard elastomeric material. Alternatively, a non-expandable layer or non-expandable particles, such as threads or pieces of threads, can also be introduced directly into the aforementioned volume-compressible layer.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Rubber cylinder sleeve, especially for web-fed rotary offset printing machines


A light source device includes: a first optical element that generates transmitted light obtained by removing a first wavelength band component from incident light and generates reflected light obtained by extracting the first wavelength band component from the incident light; a first light source that emits light that includes at least a component of the first wavelength band and that causes the light to be incident on the first optical element so as to be reflected light of the first optical element; a second light source that emits light so that light including a component of a wide second wavelength band including the first wavelength band to be transmitted light of the first optical element; and a control unit that controls driving of the first light source and the second light source. The control unit controls on/off of emission of the first and second light source emission light.

There is a conventionally known endoscope system that acquires an image and information of a biological tissue imaged by an endoscope and performs diagnosis. In order to obtain an image that enhances a special portion in a biological tissue in the diagnosis using an endoscope system, a special ray of light in a specific wavelength band different from white light being normal light is used as illumination light for the biological tissue. For example, an image that enhances a portion of a blood vessel in a biological tissue is acquired, or information regarding a biological substance in the biological tissue, for example, the concentration of hemoglobin and the oxygen saturation of hemoglobin is acquired.
There is known a light source device used for an endoscope system capable of capturing a special image using such a special ray of light, that is, a special ray of light having a spectral intensity characteristic different from that of white light (Patent Literature 1).
The known light source device includes a light source device including two light emitting diodes (LEDs) and a rotating optical filter. One of the two LEDs is a purple LED that emits light in the purple wavelength band. The other LED is a phosphor based LED having a blue LED and a yellow phosphor, and mixes blue LED light and yellow fluorescence to emit pseudo white light. The optical filter is a wavelength selection filter that allows passage of only light in a wavelength band having high absorbance with respect to a specific biological tissue, and can be inserted into and extracted from an optical path of light emitted from the phosphorbased LED.
When the optical filter is removed from the optical path in the light source device, the light emitted from the phosphorbased LED illuminates an object as white light (normal light) with no limitation of the wavelength band. In contrast, when the optical filter is inserted on the optical path, both the irradiation light emitted from the phosphor-based LED and having wavelength band limitation and the irradiation light emitted from the purple LED illuminate the object as a special ray of light. In this manner, with the spectral intensity characteristic of illumination light different from the characteristic of white light and allowing only the light of a specific wavelength band to illuminate the object, it is possible to capture an image in which a specific tissue is enhanced from among biological tissue objects.

Endoscope light source device and endoscope system


An egg testing apparatus and method utilize a vessel having marked thereupon indicia including graphics, calibrations and text, for use in determining the freshness, approximate age and recommended use for a chicken egg immersed inside the vessel in a volume of cool, fresh (i.e. non-salted) water.

It is desirable to have a convenient method and apparatus for testing chicken eggs to determine their freshness and suitability for human consumption. More particularly, it is desirable to have such a method and apparatus that can be conveniently used in a typical household kitchen.
Unfertilized chicken eggs have a typical useful life of about 31 days, if they are transported and stored in an appropriate environment. Many factors, including storage temperature and humidity, will affect the length of time that eggs can be maintained in a condition suitable for human consumption.
For eggs purchased from reliable grocers, date codes on the egg cartons can be relied upon to some extent for determining how old and fresh the eggs in the carton are likely to be, but this method is not infallible due to the many factors which can influence freshness and shelf life as the eggs make their way from the henhouse to the refrigerator shelf. Eggs from Free-Range chickens are particularly troublesome in this regard, because the eggs may not be gathered as quickly as commercial laying house eggs, given that the chickens may lay them in a place where they will not be immediately discovered.
It is known that as eggs age, they lose moisture through the shell, and a small air pocket inside the shell gets larger. It is also known that the freshness of a chicken egg may be tested by placing the egg in a vessel containing cool fresh water, and observing whether the egg floats, completely or partially in the water.
Specifically, it is known that a fresh egg will lie on its side on the bottom of the vessel. A slightly older egg will still lie generally on the bottom, but the larger end of the egg may float slightly off the bottom. As the egg continues to age, it will stand in the water with its small end touching the bottom. At a few more days of age, the egg will begin to bob up off of the bottom and float part way up in the water. A really old egg will float high in the water, perhaps even on the surface of the water.
For direct consumption, eggs which lie on the bottom are the freshest and most desirable. Eggs which are somewhat less fresh may still be quite good for direct consumption. Eggs which are less fresh yet may still be used for baking and in other indirectly consumed food products. Floating eggs should not be used for human consumption.
Although the above stated information regarding testing of eggs for freshness in water has been known for many years, the method is imprecise and prone to mistakes in interpretation. What is needed is an improved method and apparatus for more precisely determining the freshness of chicken eggs and their suitability for human consumption, in a manner that can be utilized in a typical household kitchen


Provided is a semiconductor chip that is flip-chip mounted where an inner chip pad array and an outer chip pad array, which are arranged on an inner side and an outer side of IO cells in a staggered manner, are arranged to be spaced away from each other by a predetermined gap or greater. The predetermined gap represents a gap where one via can be arranged between an inner substrate pad array and an outer substrate pad array on a substrate which faces and is connected to the inner chip pad array and the outer chip pad array. In addition, the predetermined gap represents a gap where a plated wire is interconnected and then a resist opening for etch-back can be formed. Even in a case where a space for forming an interconnection is not present between outer substrate pad arrays, interconnection characteristics of the substrate are improved.

The invention relates to a semiconductor chip that is flip-chip mounted in a substrate, and a semiconductor device on which the semiconductor chip is mounted, and more particularly, to a semiconductor chip and a semiconductor device that are suitably used for improvement of interconnection characteristics of mounting substrate.
With regard to the flip-chip mounting, in a substrate on which a semiconductor chip is mounted, a pad that is connected to a pad of the semiconductor chip is provided at a position facing the pad of the semiconductor chip. The pads are connected to each other through a bump and the like, thereby realizing electrical conduction. Hereinafter, the pad that is provided to the substrate to be connected to the semiconductor chip is referred to as "substrate pad", and the pad on the semiconductor chip is simply referred to as "pad" or "chip pad".
Along with improvement in a degree of integration, particularly, in a Large Scale Integrated circuit (LSI) such as a System on Chip (SoC), there is a tendency that a larger number of electrodes, that is, a larger number of pads is required in the semiconductor chip. With regard to an arrangement of the pad of the semiconductor chip, a so-called staggered arrangement, in which the pads are alternately arranged in two arrays at one side or both sides of input and output cells (IO cells) that are arranged in one array at each side of the semiconductor chip, is suggested. This is because the pads are significantly larger than the input and output cells, and thus the staggered arrangement has the best area efficiency.
JP-A-10-74790 discloses a technology of suppressing an area of a pad arrangement region in a case of arranging a plurality of pads on a surface of a semiconductor chip. At one side of an input and output buffer, the plurality of pads are arranged in a staggered shape in a plurality of arrays of two arrays or three or more arrays.
JP-A-2002-270779 discloses a technology of increasing an arrangement density of the TO pads without increasing a die size of the semiconductor chip. Input and output cells (IO cells) provided with an input and output circuit for electrical exchange with the outside are arranged in a ring shape at an outer peripheral portion of the semiconductor chip. The IO pads are arranged in a staggered shape with the IO cell arranged in a ring shape interposed therebetween.
In contrast, in the substrate on which the semiconductor chip is mounted, a substrate pad is arranged at a position facing the chip pad, and a through-hole via (hereinafter, simply referred to as "via") that penetrates through the entirety of the substrate or an interconnection layer that constitutes the substrate toward an opposite surface is arranged, and is interconnected to the substrate pad using the same interconnection layer as the substrate pad. Along with reduction in size of the semiconductor chip and an increase in the number of pins, a pitch between the pads becomes narrow, and congestion of the via and the interconnection becomes apparent in the substrate. For example, the via cannot be arranged in the vicinity of the substrate pad to which the via is connected, and thus leading-out of the interconnection from the substrate pad to the via becomes longer. Therefore, there are problems in that an interconnection impedance increases, electrical characteristics deteriorate, and the like. In addition, interconnection characteristics on a layout surface deteriorate and an area of the substrate increases. Therefore, for example, in a case where the substrate is a mounting substrate of an LSI package, there are problems in that the size of the package that can be accommodated increases, and the like.
JP-A-2008-252126 discloses a technology of removing a cause of an increase in semiconductor chip size in a Chip Size Package (CSP) type semiconductor device that employs Pad on Element (POE) technique and a staggered electrode pad arrangement. More specifically, when referring to FIG. 2, abstract, and paragraphs [0011] to [0013] of JP-A-2008-252126, the following technology is disclosed. Adjacent to corner cells 11 on a surface of a semiconductor chip 10, input and output cells 12 are formed so as to line up along the peripheral portion and each electrode pad 13 is formed on each of the input and output cells 12. The electrode pads 13 constitute an inner pad array and an outer pad array to form the staggered pad arrangement. However, among the electrode pads 13 that constitute the inner pad array, an electrode pad arrangement in a predetermined range adjacent to both sides of the corner cells 11 are omitted to prevent complication of interconnection patterns 21 of a carrier 20 (corresponding to the substrate) which is bump-connected to the semiconductor chip 10, and vias 22.
JP-A-10-173087 discloses a layout of a plated interconnection in a package substrate of a Ball Grid Array (BGA). The plated interconnection in the package substrate represents an interconnection on a substrate which applies an electric potential necessary for an electrolytic treatment to all electrodes to send a current so as to electrolytically plate the electrodes on front and rear surfaces of the substrate. As shown in FIG. 2 of JP-A-10-173087, the plated interconnection 9 leads out to the outside from a bonding lead.

Semiconductor chip and semiconductor device


The invention relates to a face mask arrangement for alternately administering a gas I containing nitrous oxide and a gas II devoid of nitrous oxide to a patient, comprising a face mask, two inlet flow lines I and II for gas I and a gas II, respectively, which flow lines end in a breathing interface, and an outlet flow line for evacuation of exhaled gas. The two inlet flow lines merge into a common inlet part. Each of the inlet flow lines I and II comprises an inlet valve I and II, each of which is capable of opening in response to inhalation and of closing in response to exhalation. The arrangement comprises a switching means enabling switching between inhalation through inlet flow line I and inlet flow line II depending on the patient's immediate need of gas I or gas II. The invention relates also to a system comprises the face mask arrangement and an apparatus for collecting inhalation air from patients inhaling gas containing nitrous oxide and to the use of the face mask arrangement for administration of nitrous oxide to a patient via inhalation and collecting nitrous oxide from exhaled air of a patient during the administration.

Nitrous oxide is an air pollutant which is considered at least 300 times more effective than carbon dioxide as a "green house gas". It is also considered hazardous for people exposed to it during work (e.g. doctors, dentists, nurses etc). Occupational health limits have been set to 25 ppm in many countries.
Within health care units, nitrous oxide is used within surgery, dental care, maternity care during delivery etc. due to its anaesthetic and analgesic effects on patients. The typical patient is allowed to inhale a gas mixture (=inhalation air) in which the main components are nitrous oxide, typically in concentrations of ≥10%, such as ≥20% and/or ≤80%, such as ≤70% (v/v) and oxygen. When an enhanced anaesthetic effect is desired, the mixture typically also contains a gaseous anaesthetic agent other than nitrous oxide. As a rule this agent is present in concentrations of ≤10% with typically levels being in the range of 0.25-3%, such as 0.5-2% (v/v). Suitable anaesthetic agents have often been selected amongst volatile halo-containing organic compounds.
Gas containing oxygen but no nitrous oxide means in particular oxygen gas, ambient atmosphere, air from a pressurized storage tank, physiologically acceptable mixtures of oxygen gas with gases other than nitrous oxide etc.
During health care applications, such as delivery of babies, dentists' patients etc., inhalation of a gas containing nitrous oxide is often alternated with inhalation of gas containing oxygen but no nitrous oxide. Inhalation is typically via a face mask which in some of the applications may intermittently be taken of allowing the patient to breathe ambient atmosphere. The frequency and the length of periods for a particular gas and for breathing ambient atmosphere may vary in an irregular way within a treatment, between treatments of the same kind, between patients etc.
There are several alternatives for taking care of nitrous oxide in exhalation air. Typical examples are a) catalytic decomposition, b) compression/condensation, and c) adsorption. For some years the main focus in hospitals has been on catalytically decompose nitrous oxide in highly diluted forms in a central decomposition apparatus receiving highly diluted nitrous oxide from several parts of the hospital. Typical apparatus are described in WO 2011075033 (Nordic Gas Cleaning AB), WO 20101071538 (US20110262332, Nordic Gas Cleaning AB), and WO 2002026355 (U.S. Pat. No. 7,235,222, Showa Denko KK). The decomposition efficiency has been good with more than 95% of collected nitrous oxide being decomposed to nitrogen N2 and oxygen O2 and with very low production of hazardous nitrogen oxides other than nitrous oxide (Ek & Tjus, Destruction of Medical N2O in Sweden, IVL Swedish Environmental Research Institute, and EK & Tjus, Decreased emission of nitrous oxide from delivery wards—case study in Sweden, Mitig. Adapt. Strateg. Glob. Change (2008) 13:809-818). More recently there has been an upcoming interest in apparatuses for close to patient use requiring decomposition of nitrous oxide in more concentrated forms. Apparatuses for this use are described in EP 2165756 (Linde AG) and international patent application PCT/SE2012/000044 (US61/469,381, Nordic Gas Cleaning AB). Apparatus for adsorption of nitrous oxide close to the patient are described in WO 2009095601, WO 2009095605 and WO 2009095611 (all of Air Liquid) and PCT/SE2012/000043 (U.S. 61/469,369, Nordic Gas cleaning).
Calculations have shown that proportionally large amounts (up to 25-35%) of the used nitrous oxide escape collection. Recognized leakage sources have been deficient collection at the patient's bedside and leaking from the central system for handling gas containing nitrous oxide. Poor collection at bedsides basically depends on a number of facts: a) the typical patient inhaling nitrous oxide is awake and normally controls the inhalation during medical care involving administration of nitrous oxide (mothers during delivery, dentists' patients etc.), b) the need for pain relief typically varies over time meaning that the need for nitrous oxide only is periodical during the treatment, c) breathing via a face mask is uncomfortable for a patient being awake etc. The general practice has been that patients are taking the face mask on and off depending on their subjective need for nitrous oxide. This means that nitrous oxide will be able to escape directly into ambient atmosphere, e.g. from the open mask or when the patient via his/her lungs ventilates nitrous oxide remaining in his blood and lungs. Leakage from a central gas handling systems has among others been attributed to difficulties with proper balancing of valves, flow velocity, decomposing efficiency, cost-effectiveness with respect to consumption of energy etc in relation to irregular and unpredictable time variations in incoming levels of nitrous oxide to be decomposed.
Thus, there is a need for systems enabling administration and collection of nitrous oxide and destruction of nitrous, as well as for improved face mask arrangements.
In the prior art face mask arrangements used for the administration of nitrous oxide have so far comprised (FIG. 1a):                a) A face mask 101 as such, i.e. the part of the arrangement covering the mouth, nose or both defining a breathing interface 102 between the mask 101 and a patient using the mask and a common space 103 or volume through which both exhalation and inhalation air have to pass.        b) One inlet flow lines I 104 for a first gas I containing nitrous oxide and one optional inlet flow line II 105 for a second gas II containing oxygen but no nitrous oxide. Both flow lines 104 and 105 are ending in the breathing interface 102. When there are two inlet flow lines they are merging into a common inlet part 106 before ending in the breathing interface 102. In other words the downstream parts of each of the two inlet flow lines coincide with each other. The two upstream parts 107 and 108 of the two flow lines 104 and 105 are thus non-coinciding. Each of the inlet flow lines comprises an inlet valve I 109 and II 110, respectively, which                    i) is capable of opening in response to inhalation and closing in response to exhalation, and            ii) is placed upstream of the common inlet part 106, i.e. in the non-coinciding part 107 and 108 of the inlet flow line 104 and 105, respectively.                        c) An outlet flow line 111, which is starting in the breathing interface 102 and used for evacuation of exhaled gas (exhalation air). The upstream part of this flow line 111 coincides with the downstream part of the common inlet part 106 forming a common inlet/outlet part (=common space 103) through which exhalation and inhalation air have to pass. This flow line 111 has an outlet valve 112 which i) is placed in the outlet flow line 111 at a position downstream of the common inlet/outlet part 103 (i.e. in a non-coinciding part 113 of the outlet flow line 111, and ii) is capable of opening in response to exhalation and of closing in response to inhalation.
FIG. 1b illustrates variants in which the common inlet part 106 and the common inlet/outlet part (103, =common space) fully overlap each other.
Earlier face mask arrangements for administration of nitrous oxide are illustrated in WO1982001999 (Lindkvist), WO 2007035093 (Think Global B.V.), WO 2008070918 (Dunlop) and WO 2011094018 (Nashed).
Most face masks in use nowadays are considered disturbing due to a high and irregular noise resulting from the time to time use during a medical care period.
All patent applications and issued patents cited in this specification are hereby incorporated by reference.

Face mask arrangement, system containing it and use thereof for administration


A multi-piece ceremonial sculpture that when assembled creates a symbol for unity during a wedding, anniversary, or union ceremony. The method of assembling the sculpture is to insert a first bent-shaped heart piece onto a base and then insert a second bent heart-shaped piece onto the base each by means of pegs and peg holes. The first bent heart-shaped piece and the second bent heart-shaped piece may be fastened together through a hinge connection. Finally, a pin may be inserted through the hinge connection of the first bent heart-shaped piece and the second bent heart-shaped piece to secure the two pieces together. The completed assembly resembles one three-dimensional heart, yet maintaining the identities of each individual heart symbolizing two hearts coming together into a union.

1. Field of the Invention
The present invention is directed to a method of assembling a multi-piece ceremonial sculpture and to a multi-piece ceremonial sculpture. More specifically, the present invention is a method of assembling a three-dimensional heart-shaped sculpture, that once assembled establishes a symbol of unity during a wedding or union ceremony.
2. Description of the Related Art
Various ceremonial rituals such as candles and other devices are commonly used to commemorate weddings, unions, or other various types of ceremonies. During a ceremony, two people in unison commence some sort of action such as lighting a candle, or filling a bottle with sand in order to show their union.
Current existing art also includes the assembly of a cross-like sculpture during a ceremony to celebrate a union for example, see Applicant's Method of Assembling a Multi-Piece Sculpture (U.S. Pat. No. 8,418,344). However, the assembly of a heart shaped sculpture represents two hearts of two different people coming together to form one heart in unison. Such an assembly is desired in the art and advantageous over the prior designs and commemorative rituals due to its unique nature and symbolism.


System and methods for scheduling OFDM frames are provided. Each packet is assigned to a frame bucket, this amounting to a temporary decision of when to transmit the packet. Each packet is marked with one or more metrics. The metrics are used to sort packets and make scheduling decisions. Packets are analyzed to determine their suitability for MIMO transmission.

Many schedulers have been defined that are suitable for scheduling sequential transmission of resources on a single transmission medium that has common channel conditions. These schedulers are not, in general, applicable to OFDMA scheduling in which there is a two dimensional resource (time and frequency) for use in transmitting to multiple users that will experience different channel conditions at different times, and for different frequencies within the available frequency resource.

This patent is subject to a terminal disclaimer.

Methods and systems for scheduling OFDM frames


A method of forming chip bumps of a bump chip scale semiconductor package, such a package and a chip bump are disclosed. In the bump chip scale semiconductor package produced by the above method, the chip bumps are directly formed on the chip pads of a semiconductor chip. The above chip bumps are used as the signal input and output terminals of the package and are used as surface mounting joints when the chip is mounted to a mother board.

1. Field of the Invention
The present invention relates, in general, to a method of forming the chip bumps of a bump chip scale semiconductor package, and to such a package and chip bump and, more particularly, to an improvement in such a method, package and chip bumps for directly mounting a semiconductor chip to a mother board by forming the chip bumps on the chip pads of the semiconductor chip.
2. Description of the Prior Art
The recent trend of compactness, smallness, lightness, thinness and multi-function of semiconductor-electronic appliances is promoted by high integration and high effectiveness of semiconductor chips. In order to meet such a recent trend, it is necessary to achieve compactness, smallness, lightness and thinness of semiconductor packages and to maximize the number of fins of each package. That is, it is necessary to reduce the size of the packages while improving the operational function of the packages. In this regard, the packages using solder balls as the signal input and output terminals are preferred to the packages using leads as the signal input and output terminals.
A BGA (ball grid array) semiconductor package, which is a typical package using the solder balls as its signal input and output terminals, remarkably reduces the package size and remarkably improves integration degree of the package in comparison with a typical QFP (quad flat package). However, the typical BGA package is problematic in that it fails to effectively reduce the package size due to the molding zone thus regrettably requiring a large surface mounting area when it is mounted to a mother board. Therefore, such a BGA package fails to achieve compactness, smallness, lightness and thinness of semiconductor-electronic appliances.
FIG. 9 is a sectional view showing the construction of a typical BGA package. As shown in the drawing, the BGA package comprises a semiconductor chip 1 which is attached to the top center of a PCB (printed circuit board) 7 by epoxy resin. The PCB 7 has a circuit pattern 71 on its edge portion. The chip pads of the semiconductor chip 1 are electrically connected to the circuit pattern 71 of the PCB 7 through a plurality of wires 8. A predetermined molding zone including the chip 1 and wires 8 is packaged by a molding compound 9 thus protecting the chip 1 and wires 8 from atmosphere. A plurality of solder balls 2 are formed on the bottom side of the PCB 7 and are used as signal input and output terminals of the package.
As described above, the typical BGA package uses the wires 8, so that the area of the package is enlarged due to the wire loop thus reducing the package density while surface-mounting the packages. In addition, it is difficult to design the circuit pattern on the mother board due to the enlarged area of the package. Another problem of the above BGA package resides in that interfacial separation may be generated in the junction between the parts of the package due to a change of temperature.

Method of forming chip bumps of bump chip scale semiconductor package


Methods, and communications devices employing such methods, of controlling communications with at least two calling party devices by a user of a called party device. A first call link is established between a called party device and a first calling party device. The called party device then receives a call request from a second calling party device; e.g., a call-waiting indication. A user of the called party device places the first call link on hold, and accepts the call request from the second calling party device to establish a second call link between the called party device and the second calling party device. While the user of the called party device is in communication with the user of the second calling party device, the user can cause a message to be transmitted to the first calling party device, whereby the user of the called party device can communicate information to a user of the first calling party device without interrupting communications with a user of the second calling party device. A message to the first calling party device can, for example, instruct the user to hang up, continue to hold, or leave a message for the user of the called party device.

The world is currently experiencing revolutionary changes in communications systems, brought about, in part, by the evolution of the Internet. Conventional communications systems, however, such as the Public Switched Telephone Network (PSTN), are also undergoing revolutionary changes to bring enhanced services to subscribers.
Intelligent Network (IN) services refers generally to a collection of services offered to PSTN telephony system subscribers on a pre-subscribed basis, such as Calling Number Delivery, Calling Number Blocking, Customer Originated Trace, Automatic Recall, Automatic Callback, Selective Call Forwarding, Call Waiting, Selective Call Waiting, Selective Call Rejection, and Selective Call Acceptance. The collection of IN services is continually growing as telecommunications system engineers devise both improved and novel systems and processes for providing advanced services. The medium for providing communications services, however, is gradually transitioning from the circuit-switched PSTN networks to packet-switched networks, such as the Internet, and, thus, it is desirable to provide similar services in packet-switched communications environments.
One particularly popular IN service is Call Waiting. If a subscriber to the service is engaged in a call, and a call from another party is received, the subscriber receives an indication, such as an audible tone. The subscriber can, if desired, place the first call on hold and connect to the second call. After connecting to the second call, the subscriber can then alternate between the first and second calls, as desired. Although the Call Waiting IN services has become very popular, it has the disadvantage of only allowing a subscriber to communicate with one calling party at a time. For example, if, after connecting to the second call, the subscriber desires to tell the first caller that the subscriber needs to continue with the second call, the subscriber must place the second call on hold to reconnect to the first call, inform the first caller of this need, and then reconnect to the second call. This may be undesirable if, for example, the second call is long distance, extremely urgent, or the subscriber doesn't wish the second caller to know that the subscriber was on another call.
Accordingly, there is a need in the art for methods for providing an enhanced Call Waiting service that allows a subscriber to communicate with a first calling party without interrupting communications with a second calling party. There is a further need in the art for providing such enhanced Call Waiting service within a packet-switched communications network, such as the Internet.

Methods of controlling communications with at least two calling party devices by a user of a called party device


Improved methodology and apparatus for the clinical study and treatment of sleep apnea which incorporates one or more of the following features: (1) application of mono-level, alternating high and low level, or variable positive airway pressure generally within the airway of the patient with the mono-level, high and low level, or variable airway pressure generally being coordinated with and/or responsive to the spontaneous respiration of the patient, (2) usage of adjustably programmable pressure ramp circuitry capable of producing multiple pressure ramp cycles of predetermined duration and pattern whereby the ramp cycles may be customized to accommodate the specific needs of an individual sleep apnea patient so as to ease the patient's transition from wakefulness to sleep, (3) remote control or patient-sensed operation of the apparatus, (4) employment of safety circuitry, reset circuitry and minimum system leak assurance circuitry, controls and methods, and (5) utilization of clinical control circuitry whereby sleep disorder data may be compiled and appropriate therapy implemented during a one-night sleep study.

The sleep apnea syndrome afflicts an estimated 1% to 5% of the general population and is due to episodic upper airway obstruction during sleep. Those afflicted with sleep apnea experience sleep fragmentation and intermittent, complete or nearly complete cessation of ventilation during sleep with potentially severe degrees of oxyhemoglobin desaturation. These features may be translated clinically into extreme daytime sleepiness, cardiac arrhythmias, pulmonary-artery hypertension, congestive heart failure and/or cognitive dysfunction. Other sequelae of sleep apnea include right ventricular dysfunction with cor pulmonale, carbon dioxide retention during wakefulness as well as during sleep, and continuous reduced arterial oxygen tension. Hypersomnolent sleep apnea patients may be at risk for excessive mortality from these factors as well as by an elevated risk for accidents while driving and/or operating potentially dangerous equipment.
Although details of the pathogenesis of upper airway obstruction in sleep apnea patients have not been fully defined, it is generally accepted that the mechanism includes either anatomic or functional abnormalities of the upper airway which result in increased air flow resistance. Such abnormalities may include narrowing of the upper airway due to suction forces evolved during inspiration, the effect of gravity pulling the tongue back to appose the pharyngeal wall, and/or insufficient muscle tone in the upper airway dilator muscles. It has also been hypothesized that a mechanism responsible for the known association between obesity and sleep apnea is excessive soft tissue in the anterior and lateral neck which applies sufficient pressure on internal structures to narrow the airway.
The treatment of sleep apnea has included such surgical interventions as uvulopalatopharyngoplasty, gastric surgery for obesity, and maxillo-facial reconstruction. Another mode of surgical intervention used in the treatment of sleep apnea is tracheostomy. These treatments constitute major undertakings with considerable risk of postoperative morbidity if not mortality. Pharmacologic therapy has in general been disappointing, especially in patients with more than mild sleep apnea. In addition, side effects from the pharmacologic agents that have been used are frequent. Thus, medical practitioners continue to seek non-invasive modes of treatment for sleep apnea with high success rates and high patient compliance including, for example in cases relating to obesity, weight loss through a regimen of exercise and regulated diet.
Recent work in the treatment of sleep apnea has included the use of continuous positive airway pressure (CPAP) to maintain the airway of the patient in a continuously open state during sleep. For example, U.S. Pat. No. 4,655,213 and Australian patent AU-B-83901/82 both disclose sleep apnea treatments based on continuous positive airway pressure applied within the airway of the patient.
Also of interest is U.S. Pat. No. 4,773,411 which discloses a method and apparatus for ventilatory treatment characterized as airway pressure release ventilation and which provides a substantially constant elevated airway pressure with periodic short term reductions of the elevated airway pressure to a pressure magnitude no less than ambient atmospheric pressure.
U.S. Pat. No. 5,199,424 and published PCT Application No. WO 88/10108 describes a CPAP apparatus which includes a feedback system for controlling the output pressure of a variable pressure air source whereby output pressure from the air source is increased in response to detection of sound indicative of snoring. According to additional embodiments of the apparatus disclosed in these references, a pressure ramp cycle (i.e., a gradual increase in output pressure) may occur upon initial activation of the apparatus which gradually increases output pressure from a predetermined minimum to a predetermined maximum or therapeutic pressure specifically selected for the patient.
Publications pertaining to the application of CPAP in treatment of sleep apnea include the following:
1. Lindsay, D. A., Issa F. G., and Sullivan C. E. "Mechanisms of Sleep Desaturation in Chronic Airflow Limitation Studied with Nasal Continuous Positive Airway Pressure (CPAP), "Am Rev Respir Dis, 1982; 125: p. 112. PA1 2. Sanders N. H., Moore S. E., Eveslage J. "CPAP via nasal mask: A treatment for occlusive sleep apnea, Chest, 1983; 83: pp. 144-145. PA1 3. Sullivan C. E., Berthon-Jones M. Issa F. G. "Remission severe obesity-hypoventilation syndrome after short-term treatment during sleep with continuous positive airway pressure, Am Rev Respir Dis, 1983; 128: pp. 177-181. PA1 4. Sullivan C. E., Issa F. G., Berthon-Jones M., Eveslage J. "Reversal of obstructive sleep apnea by continuous positive airway pressure applied through the nares, Lancet, 1981; 1: pp. 862-865. PA1 5. Sullivan C. E., Berthon-Jones M. Issa F. G. "Treatment of obstructive apnea with continuous positive airway pressure applied through the nose. Am Rev Respir Dis, 1982; 125: p. 107. Annual Meeting Abstracts. PA1 6. Rapoport D. M., Sorkin B, Garay S. M., Goldring R. N. "Reversal of the `Pickwickian Syndrome` by long-term use of nocturnal nasal-airway pressure," N Engl J. Med, 1982; 307: pp. 931-933. PA1 7. Sanders M. H., Holzer B. C., Pennock B. E. "The effect of nasal CPAP on various sleep apnea patterns, Chest, 1983; 84: p. 336. Presented at the Annual Meeting of the American College of Chest Physicians, Chicago Ill., October 1983. PA1 8. Sanders, M. H. "Nasal CPAP Effect on Patterns of Sleep Apnea", Chest, 1984; 86: 839-844.
Although mono-level positive airway pressure or CPAP has been found to be very effective and well accepted, it suffers from some of the same limitations, although to a lesser degree, as do the surgery options; specifically a significant proportion of sleep apnea patients do not tolerate CPAP well. Thus, development of other viable non-invasive therapies has been a continuing objective in the art.


An advanced intelligent communication system is provided as an overlay application to, for example, one or more private networks. The system adds increased flexibility to an existing private network by facilitating remote access to the private network from non-network locations or stations. The system authorizes the remote access to the private network based on a calling party number of the non-network station and/or an authorization code entered by the remote calling party. Once authorized, the remote calling party is then enabled to terminate a call to a private network station identified by a private network telephone number.

1. Field of the Invention
The present invention generally relates to an apparatus and method for facilitating remote communications access to a multiple location private network within a telecommunications network. More particularly, the present invention relates to an Advanced Intelligent Network (AIN) application for providing multiple location networking capabilities to remote callers accessing a private network from an off-network location.
2. Acronyms
The written description provided herein contains acronyms which refer to various communication services and system components. Although known, use of several of these acronyms is not strictly standardized in the art. For purposes of the written description herein, acronyms will be defined as follows:
10D--10 Digit Trigger PA0 AC--Authorization Code PA0 ATG--Alternate Trunk Group PA0 AIN--Advanced Intelligent Network PA0 CCIS--Common Channel Interoffice Signaling PA0 CCS--Common Channel Signaling PA0 CDN--Called Number PA0 CGN--Calling Number PA0 CENTREX--Central Exchange Service PA0 CO--Central Office PA0 CPN--Calling Party Number PA0 CPR--Call Processing Record PA0 DID--Direct Inward Dialing PA0 DLN--Dialed Line Number PA0 DRS--Data and Reports System PA0 EO--End Office PA0 ISCP--Integrated Service Control Point PA0 IXC--Interexchange Carrier PA0 LATA--Local Access and Transport Area PA0 LCS--Local Calling Scope PA0 MF--Multi-Frequency PA0 NANP--North American Numbering Plan PA0 NPA--Number Plan Area PA0 NXX--Central Office Code PA0 ORN--Office Route Number PA0 PBX--Private Branch Exchange PA0 PIC--Primary Interexchange Carrier PA0 POP--Point of Presence PA0 PRI--Primary Rate Interface PA0 PTG--Primary Trunk Group PA0 PSTN--Public Switched Telephone Network PA0 RAF--Remote Access to Facilities PA0 RI--Route Index PA0 SATG--Second Alternate Trunk Group PA0 SCE--Service Creation Environment PA0 SCP--Service Control Point PA0 SMDR--Station Message Detail Recording PA0 SMS--Service Management System PA0 SS7--Signaling System 7 PA0 SSP--Service Switching Point PA0 STP--Signaling Transfer Point PA0 TAT--Termination Attempt Trigger PA0 TCAP--Transaction Capabilities Applications Part PA0 TG--Trunk Group PA0 TN--Telephone Number
3. Background and Material Information
In recent years, a number of new telephone service features have been provided by an Advanced Intelligent Network (AIN). The AIN evolved out of a need to increase the capabilities of the telephone network architecture to meet the growing needs of telephone customers. The AIN architecture generally comprises two networks, a data messaging network and a trunked communications network. The trunked communications network handles voice and data communications between dispersed network locations, whereas the data messaging network is provided for controlling operations of the trunked communications network.
An illustration of the basic components of an AIN architecture is shown in FIG. 11. As shown in FIG. 11, Service Switching Points (SSPs) 64-70 are provided for sending and receiving data messages from a Service Control Point (SCP) 56 via Signaling Transfer Points (STPs) 58-62. The data messages are communicated to and from the SSPs 64-70 and the SCP 56 along a Common Channel Signaling (CCS) network 88. Each SSP 64-70 routes telephone calls between a plurality of dispersed network stations 172-186. For example, SSPs 64-70 may rout a telephone call between a calling station (e.g., station 172) and a called station (e.g., station 184) through trunks 90 and lines 92 (e.g., telephone lines). Stations 172-186 may comprise various customer or terminal equipment, such as a telephone unit (wired, cellular or mobile), a facsimile machine, and/or a modem attached to a personal computer. For more information regarding AIN, see Berman, Roger K., and Brewster, John H., "Perspectives on the AIN Architecture," IEEE Communications Magazine, February 1992, pp. 27-32, the disclosure of which is expressly incorporated herein by reference in its entirety.
A number of features provided by the prior AIN or AIN-type intelligent networks relate to specialized call processing of incoming calls and call traffic.
For example, U.S. Pat. No. 4,191,860, to WEBER, provides for special processing of calls, such as INward WATS (Wide Area Telephone Service) calls, via a number of local switching offices based on information stored in a central database. The central database is located at a remote Service Control Point (SCP). The local and toll offices of the telephone network compile a call data message via a common channel interoffice signaling (CCIS) link to the central database. The database at the SCP translates the dialed INWATS number into an unlisted destination telephone number based on an originating area code. The unlisted destination number is then returned to the central offices via the CCIS link, and the call is completed. When the number of telephone calls to the unlisted number per unit time exceeds a threshold, the database instructs the telephone system to inhibit such calls from being connected for a predetermined period of time.
U.S. Pat. Nos. 4,611,094 and 4,611,096, both to ASMUTH et al., disclose a system for providing custom incoming telephone call processing services to a subscriber operating at geographically diverse locations. A subscriber program stored in a central database is accessed to provide instructions to the SSPs to complete incoming calls to one of the subscriber locations in accordance with special services defined by the subscriber. The subscriber program controls the Action Control Points (ACPs) to string together the desired call processing capabilities to process each call. Specified parameters stored in the program, such as time of day, caller location and data inputted by the caller, determine the final destination to which each call should be completed.
U.S. Pat. No. 5,247,571, to KAY et al., discloses an Area Wide Centrex system to provide specialized calling features to stations connected to a plurality of central offices. Each of the central office switching points connects to a number of local telephone lines. The features are extended to the local telephone lines by taking the programming intelligence out of the central offices and moving it to a database located in a central location, such as an SCP. Service features are controlled by the central database and are changed by reprogramming the service logic located at the central database. A variety of service features are provided including extension number dialing and call transfer across groups of lines connected to different exchanges. In addition, a work-at-home feature is provided such that when a user from a predetermined home telephone number dials a desired number, access may be granted to certain features of the Area Wide Centrex system.
While prior AIN or AIN-type intelligent network applications have provided various call screening and processing features to subscribers and users, such past attempts have not extended the advantages of AIN functionality to private networks. In particular, prior attempts have not provided a remote access capability to supplement and enhance services to subscribers or users of an existing private network (e.g., networks comprising one or more PBX and/or Centrex systems, networks comprising one or more types of switch types, and networks comprising one or types of trunk configurations) to facilitate multiple location communication and provide increased flexibility to private network users. For example, in private networks having geographically dispersed locations and served by different switches, past attempts have not permitted remote callers to access the private network from any non-network location. This type of capability could enable subscribers to place local area and long distance calls to other locations on the private network at substantially reduced cost. Past attempts have also failed to provide adequate security screening features to control access to private networks from off-network locations through various screening or authorization features, including providing authorization through the use of different types of identifiers.
Such features would be desirable and provide advantages to subscribers and users of private communication networks, such as large multi-location/multi-switch corporate subscribers and government agencies, that desire ease of inter- and intra-location calling, especially from, for example, existing CENTREX and Private Branch Exchange (PBX) sites.

Method and apparatus for facilitating remote communications access to multiple locations within a telecommunications network


A rectifier comprising a metal-insulator-metal (MIM) structure. The insulator may be a native oxide with an adjacent layer of graphene. In one implementation, the rectifier is used in an electromagnetic energy collector consisting of a planar waveguide formed of multiple material layers having at least two different dielectric constants. MIM rectifiers are aligned with mirrors are formed within the waveguide core. In some arrangements, a plurality of MIM rectifiers are disposed in a column or 3D array beneath each mirror.

Technical Field
This patent application relates to an electromagnetic energy collection device and specifically to rectifiers for energy harvesting or general rectification of ultra-high frequency energy.
Background Information
The integration of photonic devices for low-cost on-chip optical interconnects is of great interest for high speed computing. Additionally, there is a desire in the solar energy industry to tap the potential high theoretical conversion efficiency of rectennas, where highly concentrated coherent light in a waveguide could enable higher rectenna efficiencies.
One of the key elements for both end uses is the efficient integration of a waveguide and a detector. Coupling of light from a planar waveguide to a monolithically integrated detector, such as a tunnel diode or rectenna, can be accomplished in several ways, but it has remained a challenge to do so with high efficiency across a broad spectral band.
There are a variety of applications for tunnel diodes and rectennas, including energy harvesting, rectification, and harmonic mixing for down and up conversion. Dipole, bowtie and spiral have been some of the antenna geometries explored, and the rectifying diodes include p-n junction semiconductor diodes, Schottky metal-semiconductor diodes, and MIM tunnel diodes. The choice of rectifier is dependent on the frequency of electromagnetic energy. The diodes listed above have increasing bandwidth as they rely less upon a capacitive depletion layer for asymmetry of current flow. For conversion of terahertz (THz) frequencies, tunnel diodes made from metal-insulator-metals are the only type of junction to that has the speed to rectify IR and potentially visible light.
Although there has been some success in fabricating dissimilar MIM diodes and obtaining rectification of infrared (IR) energy, the efficiencies reported have been less than 1% due to the limited asymmetry in the current vs. voltage characteristics of the diode.
Some earlier work experimented with creating a Schottky-like diode from a single layer of graphene in contact with a metal electrode, as reported by Nourbakhsh, A, et. al, Applied Physics Letters, 97, 1631010 (2010).
Reference may also be made to rectenna apparatus for solar energy collection, such as in U.S. Pat. No. 8,437,082 entitled "Orthogonal scattering features for solar array" and U.S. Pat. No. 8,735,719 entitled "Leaky solar array with spatially separated collectors", and U.S. Patent Publication 2014/0182656 entitled "Wideband light energy waveguide and detector", each assigned to AMI R&D, the assignee of the present application, and each of which are hereby incorporated by reference.

Graphene coupled MIM rectifier especially for use in monolithic broadband infrared energy collector