A method of purifying an organometallic compound comprising    distilling the organometallic compound for purification while blowing an inert gas through a vapor of the organopolysiloxane, thereby removing from the organometallic compound an impurity having a higher vapor pressure than the organometallic compound.

This invention relates to a purification method for organometallic compounds, especially trimethylaluminum. More specifically, this invention is concerned with a method for lowering the concentration of an impurity, especially an organosilicon compound, which is contained in an organometallic compound such as trimethylaluminum effectively used for the production of a compound semiconductor and has a higher vapor pressure than the organometallic compound. This invention is also concerned with a purified organometallic compound obtained by the purification method.
Compound semiconductor materials such as gallium arsenide, indium phosphide and gallium phosphide are well known materials having uses in electronics industry in such applications as microwave oscillators, semiconductor light-emitting diodes, lasers and infrared detectors. The quality of a compound semiconductor available from an epitaxial growth of an organometallic compound is significantly controlled by impurities in the organometallic compound as a raw material. Therefor, high purity is required for the organometallic compound to obtain the compound semiconductor material with a high function.
Typical examples of organometallic compounds used in the production of compound semiconductors include trimethylgallium, trimethylindium, and trimethylaluminum. Among these, trimethylgallium and trimethylindium are produced from gallium chloride and trimethylaluminum and from indium chloride and trimethylaluminum, respectively, and the purities of trimethylgallium and trimethylindium are considered to depend on the purity of trimethylaluminum as their starting material. It is, accordingly, the most important step in the production of these organometallic compounds to highly purify trimethylaluminum.
The impurities in an organometallic compound to be purified include hydrocarbon compounds and in addition, organometallic compounds and metallic compounds containing metals different from the metal in the organometallic compound to be purified. Among these impurities, those having higher or similar vapor pressures compared with the organometallic compound to be purified may form impurity inclusions in a compound semiconductor to be produced from the purified organometallic compound if they still remain even after the purification, and therefore, are considered to be particularly harmful.
Among impurities having high vapor pressures, organosilicon components with Group IV metals contained therein are desired to be removed completely, because they lower electrical properties and optical properties of Group III-V compound semiconductors such as gallium arsenide if they are included in the compound semiconductors.
As processes for removing impurities having high vapor pressures, there have heretofore been reported adduct purification processes (JP-B 5-35154 and JP-A 62-185090), processes involving distillation in contact with metallic sodium or metallic potassium (JP-A 62-132888 and JP-A 8-12678), and processes for purifying liquid organometallic compounds by cooling and solidifying them (JP-A 2003-518007).
However, the adduct purification processes and the processes involving distillation in contact with metallic sodium or metallic potassium are accompanied by many drawbacks in that, as they require the addition of a solvent and the chemical for the treatment to an organometallic compound to be pured, the purity of the solvent and chemical need to be made very high before their addition, the solvent and chemical have to be treated after use, the solvent and chemical is costly, and the handling of the solvent and chemical is dangerous. The purification processes involving cooling and solidification of organometallic compounds also have problems in that applicable organometallic compounds are limited and the removal of impurities is insufficient.

Purification method for organometallic compounds and organometallic compounds obtained therefrom


The drive mechanism is suitable for a permanent delivery of a drug from a compact drug delivery device, which may be carried on the body. The drive mechanism comprises a flexible advance cable bearing a coupling feature of longitudinal extension. The advance cable is guided by a guide means. A drive means engages the coupling feature and thus enables an advancement of the advance cable according to the guide means. An end piece is provided to push a plug or bung of a cartridge containing a drug, and the end piece is driven by the advance cable. The drive means is permanently engaged with the coupling feature. This allows a permanent advancement of the plug or bung by means of the drive mechanism.

EP 1 372 768 B1 describes a drive mechanism for an injection device in which a semi-rigid belt with a track is used to drive a piston member. A belt drive means is provided to drive the belt a preselected way. It comprises a tooth for a selective engagement with the track and allows an advancement of the belt only in one direction.

Drive mechanism for a drug delivery device and drug delivery device


A plurality of memory cells each storing n values (n is a natural number which is not smaller than 3) are arranged in a matrix form in a memory cell array, and each memory cell is connected with a word line and a bit line. Each memory cell stores the n-valued data by a first write operation and a second write operation. A read section sets a potential of a word line, and reads data from a memory cell in the memory cell array. If data read by the read section and written in the second write operation includes an uncorrectable error, a control section changes a potential of a word line supplied to the read section when reading data written in the first write operation.

1. Field of the Invention
The present invention relates to a NAND flash memory using, e.g., an EEPROM, and more particularly to a semiconductor memory device capable of storing multivalued data in a single memory cell.
2. Description of the Related Art
In a NAND flash memory, a plurality of memory cells arranged in a column direction are connected in series to constitute a NAND cell, and each NAND cell is connected with a corresponding bit line through a select gate. Each bit line is connected with a latch circuit which latches write data and read data. There has been proposed a non-volatile semiconductor memory device capable of storing multivalued data in this NAND flash memory (see, e.g., Jpn. Pat. Appln. KOKAI Publication No. 2000-195280).
In recent years, miniaturization of an element has advanced, and a distance between cells is decreasing. Therefore, an influence of a floating gate capacity between cells adjacent to each other is becoming large. Specifically, there has arisen a problem that a threshold voltage of a cell in which data has been previously written fluctuates due to a threshold voltage of a cell which is adjacent to the former cell and in which data is subsequently written. In particular, since a multivalued memory which stores a plurality of sets of data each consisting of two or more bits in a single cell stores a plurality of sets of data by using a plurality of threshold voltages, a distribution of a threshold voltage corresponding to one set of data must be controlled to be extremely narrowed. Therefore, the influence of the threshold voltage of the adjacent cell is prominent.
In order to solve this problem, in a memory cell in which one-bit (a first page) data is stored, one-bit (the first page) data is written in an adjacent memory cell to reach a threshold voltage (a V-level) lower than an original threshold voltage before storing the next data. After writing the data in this adjacent memory cell, writing to increase the voltage to the original threshold voltage (a word line potential "b" (V<=B)) is carried out in writing a second page. However, it is hard to recognize that data of the first page has been written with to the original threshold voltage or the lower threshold voltage before and after writing the second page. Therefore, in order to recognize this, there has been proposed a write scheme by which a flag memory cell (which will be referred to as a flag cell) is prepared in accordance with each page and a read operation is performed in accordance with data in this flag cell (see, e.g., Jpn. Pat. Appln. KOKAI Publication No. 2004-192789).
In a case where data of the second page is written based on this write scheme, when data of the first page is "1" and data of the second page is "0", data in the memory cell is changed from "0" to "1", a threshold voltage is increased to, e.g., a level A. Further, when data of the first page is "0", its threshold voltage is determined as a voltage including the level A. Therefore, their threshold voltage distributions overlap each other. Therefore, when writing is interrupted due to, e.g., an abnormal cutoff of a power supply during writing the second page, there occurs a problem that the previously written first page data is also destroyed. Therefore, there has been demanded a semiconductor memory device which can avoid destruction of data of the first page even if writing the second page is abnormally interrupted.

Semiconductor memory device which prevents destruction of data


An apparatus for generating hydrogen gas in which hydrogen gas of a high purity is supplied to a hydrogen-utilizing device by using a decahydronaphthalene/naphthalene reaction. The apparatus includes a storage tank in which decahydronaphthalene is stored as a crude fuel, a reaction tank which has a catalyst and a heater for heating the catalyst and which causes dehydrogenation of decahydronaphthalene supplied from the storage tank to the heated catalyst, and a separation tank in which hydrogen-rich gas is separated out from naphthalene and hydrogen gas supplied from the reaction tank by using a hydrogen separation film and from which the separated hydrogen gas is discharged.

1. Field of the Invention
The present invention relates to an apparatus for generating hydrogen gas (gaseous hydrogen), and particularly to an apparatus for generating hydrogen gas which can be mounted in a vehicle such as an electric vehicle and can supply hydrogen gas to fuel cells mounted in the vehicle.
2. Description of the Related Art
Conventionally, an electric vehicle carries fuel cells as a power source for obtaining driving force of the vehicle and is loaded with hydrogen, as a fuel which is used to carry out power generation in the fuel cells, or with a crude fuel which is used to produce hydrogen. Hydrogen is loaded on the electric vehicle in the form of a cylinder (tank) filled with compressed hydrogen gas or in the form of a hydrogen-absorbing alloy or hydrogen-absorbing material into which hydrogen is absorbed. Further, an electric vehicle loaded with a crude fuel is loaded with a hydrocarbon crude fuel, such as methanol or gasoline, and includes a hydrogen generator for generating hydrogen-rich gas by steam reforming the crude fuel.
However, hydrogen storage density of the hydrogen-absorbing alloy or hydrogen-absorbing material is not sufficient for use in fuel cells of an electric vehicle, and it is very difficult to control storage and absorption of hydrogen. Compared with an electric vehicle loaded with hydrogen, an electric vehicle loaded with a crude fuel has the advantage of a longer travelling distance on one supply of fuel, and also has the advantage that the crude fuels such as hydrocarbons are easier to handle and is safer to transport than hydrogen gas.
Decahydronaphthalene (Decalin), which is a hydrocarbon, has a vapor pressure of approximately zero at ordinary temperatures (the boiling point is close to 200° C.) and is easy to handle. Accordingly, the possibility that decahydronaphthalene can be used as the above-described crude fuel has been foreseen.
As a dehydrogenation method for decahydronaphthalene, a method has been known in which decahydronaphthalene is irradiated with light in the presence of a transition metallic complex containing at least one kind of transition metal selected from cobalt, rhodium, iridium, iron, ruthenium, nickel and platinum, and thus hydrogen is removed from the decahydronaphthalene (see Japanese Patent Application Publication (JP-B) No. 3-9091). Further, a method has also been known in which decahydronaphthalene is irradiated with light in the presence of a rhodium complex of an organic phosphorous compound or in the presence of an organic phosphorous compound and a rhodium compound, to produce hydrogen from the decahydronaphthalene (see Japanese Patent Application Publication (JP-B) No. 5-18761).
However, when one of the above-described conventional hydrogen generating methods is applied to a hydrogen-utilizing device such as fuel cells of an electric vehicle, a reaction conversion ratio is low, and naphthalene, unreacted decahydronaphthalene and the like produced by the dehydrogenation, are included. Accordingly, there exists a problem that hydrogen partial pressure is low and the efficiency of the hydrogen-utilizing device deteriorates.


An inner insert for a passage opening in an outer insert for an EUV radiation source is embodied in multiple parts and/or has a plurality of sections that extend in the longitudinal direction and have different internal diameters (di, da).

Used radiation in the EUV range can be generated in an EUV radiation source by igniting a source plasma in a source chamber of the EUV radiation source. US 2011/0089834 A1 describes an embodiment of an EUV radiation source with an electrode plasma generation device. EP 1 774 838 B1 discloses an inductively coupled plasma source.
An EUV radiation source is also known for example from Blackborow et al. (2010), "EUV source development for AIMS and blank inspection;" Proc SPIE, 7636.
EUV radiation sources are used in illumination systems for projection exposure apparatuses, in particular for EUV lithography inspection apparatuses and metrology systems. A corresponding projection exposure apparatus is known for example from WO 2009/100 856 A1.
In some examples, during the operation of the projection exposure apparatus, it is essential that the EUV radiation source generates radiation pulses of substantially consistent, constant intensity. It has been shown that this is not directly the case after wear parts of the radiation source are exchanged. EUV radiation sources therefore typically need to undergo a lengthy and complex conditioning process after an exchange of wear parts.

EUV radiation source, insert for an EUV radiation source and insert for an insert for an EUV radiation source


A lighting device has a base, an optic defining an optical chamber, a driver circuit positioned in electrical communication with the base, and a flexible circuit board positioned within the optical chamber along and generally circumscribing a longitudinal axis of the optical chamber and in electrical communication with the driver circuit. The flexible circuit board may comprise a plurality of longitudinal sections. Each longitudinal section may comprise a first inclined section, a second inclined section, and a plurality of light-emitting diodes (LEDs). The first inclined section may be positioned in the direction of the base relative to the second inclined section. The lighting device may further include a longitudinal translation device to translate longitudinally part of the flexible circuit board.

The lighting industry is gradually moving towards the use of light-emitting semiconductors, such as light-emitting diodes (LEDs) due to their advantages of lower energy consumption than traditional incandescent bulbs and their lack of hazardous materials, such as mercury, which is present in compact fluorescent light bulbs (CFLs). However, in general, LEDs are positioned on a printed circuit board (PCB) that is opaque, causing light emitted from the LED to be emitted in a hemisphere generally opposite the PCB. As such, lighting devices employing PCB-based LEDs have needed to take extraordinary measures to accommodate the rigidity of traditional PCBs while still achieving desirable light distribution, namely, approximately uniform light in a 4π steradian distribution.
Flexible circuit boards ("flex circuits") present an alternative to traditionally rigid PCBs. Flex circuits may have a curvature along one or more axes. Additionally, flex circuits may be folded for a more abrupt change of direction beyond a minimum radius of curvature, below which the circuit folds.
Additionally, the cost of LED-based lighting devices has tended to be higher than lighting devices including other methods of emitting light due to the relatively high price of LEDs. Accordingly, fewer numbers of LEDs were economically feasible to include in a lighting device. As such, the amount of light emitted by each individual LED of a lighting device needed to be maximized, so as to produce enough light sufficient for consumer use. As the efficiency of LEDs, namely, the amount of light emitted, decreases with an increase of temperature beyond a certain threshold, an LED-based lighting device frequently employed a heat sink to increase the thermal dissipation capacity of the lighting device. A heat sink adds cost to a lighting device, as well as tending to add significant weight, as typical heat sinks are fabricated of aluminum and alloys thereof. However, as the cost of LEDs has come down, the need to operate each individual LED at a peak efficiency associated with a certain peak operating temperature is no longer necessary to maintain commercial viability, and indeed, it is becoming more economically disadvantageous to include a heat sink. However, it is still desirous to operate LEDs as close to their peak operating temperatures as is feasible. Accordingly, there is a need in the art that
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.

Lighting device with flexible circuits having light-emitting diodes positioned thereupon and associated methods


A magnetically levitated transport device provides levitation and propulsion of a vacuum carriage. An air carriage is moved by conventional means through both linear and angular displacements. Non-magnetic coils mounted on the air carriage interact with permanent magnets mounted on the vacuum carriage to magnetically link the carriages together using Lorentz forces. The non-magnetic coils, which are exposed to the fields generated by the permanent magnets, produce the Lorentz forces when driven by drive currents in response to inputs received from position sensors. In one embodiment, power requirements are reduced by adding permanent magnets to the air carriage that interact with some of the permanent magnets on the vacuum carriage to provide forces that substantially levitate all of the static load.

This invention relates to magnetic levitation systems, and more particularly to using magnetic levitation in linear transport systems which transport materials between process stations in a vacuum environment.
The use of linear transport systems is well known throughout various industries. For example, many manufacturing operations utilize linear transport systems to move the materials being fabricated into and out of vacuum chambers, where the materials are treated. The use of magnetic levitation enables the transport mechanism to be substantially free of dust and other particulates. For example, Enomoto U.S. Pat. No. 5,288,199 describes a transporting device which uses a magnetically levitated floating arm to transport semiconductor wafers between multiple chambers of a wafer fabrication system. Enomoto relies on the use of proportional/integrating/differentiating (PID) control circuits to maintain the slider arm in the proper horizontal position and a judging circuit to determine whether a wafer is present on the arm.
In another system, Oshima et al. U.S. Pat. No. 5,241,912 describes a magnetically floating carrier in which electromagnets act through a reduced thickness portion of the wall of a lateral member. Oshima, like Enomoto is directed toward an apparatus for transporting semiconductor wafers in a vacuum chamber. Oshima utilizes a sealed tubular portion that is typically maintained at atmospheric pressure, while a carrier that slides along the tubular portion is disposed in the vacuum. A drive system is disposed within the tube that includes two pairs of magnetic bearings and various position sensors. The magnetic bearings interact with magnetic targets that are placed on the carrier to cause the carrier to laterally float back and forth. In order to reduce the power requirements of the system, Oshima discloses a technique whereby the thickness of certain portions of the outer wall of the tubular member (i.e., where the magnetic targets are placed) is reduced to improve the linkage between the bearings and the targets.
Another variation of a linear semiconductor transportation apparatus is disclosed by Belna U.S. Pat. No. 4,624,617. Belna's device utilizes a linear induction motor to levitate and linearly propel a car that supports a semiconductor wafer. The motor includes permanent magnets disposed on the car that interact with individually energizable electromagnets disposed along a track that the car travels along. The car is guided down the track by a pair of permanent magnet grooves (i.e., "V" shaped) in the underside of the car and pair of "V" shaped magnets that extend down from the track to the grooves. The electromagnets act to offset the natural magnetic forces between the grooves and the "V" shaped magnets such that the car levitates above the track. As the electromagnets are sequentially energized, the car moves linearly along the track.
While each of the above described devices may be adequate for transporting one or more semiconductor wafers, none of the devices are capable of transporting objects of greater weight, possibly even including cassettes holding multiple wafers. For example, Oshima describes how extra power would be necessary to transport single wafers without reducing the thickness of the tubular walls. The extra power, besides being a negative factor itself, may cause severe problems due to heat generation. In fact, the heat dissipation problem is particularly applicable in applications such as Belna in which the electromagnets may not be located in a region at atmospheric pressure.
In view of the foregoing, it is an object of this invention to provide improved magnetically levitated transport devices that operate with reduced power requirements.
It is also an object of this invention to provide improved magnetically levitated transport devices that are capable of transporting objects weighing more than a pound.

Magnetically levitated robot and method of increasing levitation force


Methods and systems are presented for custom caching. Application threads define caches. The caches may be accessed through multiple index keys, which are mapped to multiple application thread-defined keys. Methods provide for the each index key and each application thread-defined key to be symmetrical. The index keys are used for loading data from one or more data sources into the cache stores on behalf of the application threads. Application threads access the data from the cache store by providing references to the caches and the application-supplied keys. Some data associated with some caches may be shared from the cache store by multiple application threads. Additionally, some caches are exclusively accessed by specific application threads.

Technological advancements have led to more sophisticated and powerful data management systems. Data processing in such systems require efficient handling a large number of data transactions (e.g. data reads, writes, etc.).
The advent of the Internet and the World-Wide Web (WWW) combined with the development of network-based commerce system applications have enabled companies to transact business globally in real-time. Such network-based commerce systems may process large amounts of data transactions from geographically dispersed users. The users may enter transactional requests over communications lines that result in the persistant storage of data in a master information source (data store). In several cases, back-end systems (e.g., database servers, etc.) support the data store and interact with other systems or services to map the data between a persistent or relational form into an object form that is more readily utilized by software applications.
Furthermore, software developers typically expend a large amount of time and energy in managing access related to the data store and in managing memory usage within their applications, which is used to manipulate data acquired from the data store within the scope of their applications. One tool that developers rely on for improving processing throughput of their applications is a cache manager or cache service. However, cache services are typically not customizable and are not extensible by the developers within their applications. This is so, because caching services are generally implemented as black boxes having a defined set of generalized and static services or features. As a result, data store access and memory management are tasks that developers still largely have to account for within their individual applications. These tasks are time consuming and in some cases not optimal because some developers may not be as adept as other developers in handling these tasks.


A lighting and/or signaling device for a motor vehicle, comprising at least one light source emitting a light beam and at least one optical guide in which the light beam propagates, the optical guide comprising: a first face forming an exit face for the light beam, and a second face, opposite to the exit face, forming a reflection face for the light beam, such that the light guide is associated with a diffusing screen disposed opposite the reflection face of the light guide.

1. Field of the Invention
The object of the present invention is a lighting or signaling device equipping a motor vehicle, comprising at least one optical guide able to produce diffusion of the light over at least part of its length. The invention also concerns a vehicle comprising such a lighting or signaling device.
2. Description of the Related Art
In the field of motor vehicle lighting and signaling, optical guides are being used more and more frequently. An optical guide is, very schematically, an elongate element made from transparent material, generally in the form of a cylinder. Close to one of the ends of the guide, referred to as the guide entry face, one (or more) light source is disposed, for example a small light source of the light emitting diode type: the light rays emitted by this source propagate by total reflection in the length of the guide in the direction of its opposite end, referred to as the end face of the guide. Some of the light rays propagating in the guide will emerge from it in the so-called front face of the guide by virtue of the presence of reflecting elements disposed on the so-called rear face of the guide, opposite to the previous one. These reflecting elements consist for example of prisms. The guide thus emits light over its entire length. It has the advantage of being able to take very varied geometric forms, be it rectilinear or in an arc of a circle, and bring an illuminating surface even into areas of the vehicle headlight or light that are not very accessible. It thus participates greatly in the style of the headlight or light. However, existing light guides are open to improvement: this is because it is often tricky to ensure an identical illumination level between the first and second ends of the guide, particularly if it has a significant length, the illumination level having a tendency to decrease on moving away from the entry face of the guide. Moreover, it is also tricky to ensure a homogeneous appearance to the guide whatever the angle of vision that there is of the guide, the light emerging from the guide having an angular distribution that is often insufficiently broad. However, it is an important point according to the arrangement of the guide and its shape inside the headlight or light: there is a tendency to design the guide so that it illuminates mainly in the axis of the vehicle in order to meet photometric standards. However, it also proves important to have a homogeneous and visually agreeable illuminated appearance also when the observer moves away from the longitudinal axis of the vehicle. It may also be wished to improve the optical efficiency of the guide since there may be leakages of light therein lost through the rear face of the guide in particular.
It is already known from the patent EP 1 443 265 how to associate a light guide with a reflector situated at the rear of the light guide in order best to limit the leakages of light and thus improve the optical efficiency of the guide.
The aim of the invention is then to obtain an improved light guide that makes it possible in particular to have a more homogeneous illuminated appearance, particularly in a wide range of vision angles of incidence.

Lighting or signal device with an optical guide for a motor vehicle


An improved dielectric thin film and a capacitor with the same for a semiconductor and a fabrication method thereof capable of preventing leakage current in operation, which dielectric thin film includes (Ba, Sr)TiO.sub.3 containing Ta, and which the capacitor includes a substrate; an interlayer insulation layer formed on a substrate, thereby exposing a predetermined portion of the substrate to the outside; a lower electrode formed on a predetermined portion of the interlayer insulation layer including the exposed portion of the substrate; a dielectric thin film consisting of (Ba, Sr)TiO.sub.3 containing Ta and formed on the interlayer insulation film including the lower electrode; and an upper electrode formed on the dielectric thin film.

1. Field of the Invention
The present invention relates to a dielectric thin film (e.g., for a capacitor in a semiconductor apparatus) and a fabrication method thereof, and in particular to an improved dielectric thin film and a fabrication method thereof capable of preventing leakage current in operation by providing a dielectric thin film.
2. Description of the Conventional Art
As well known to those skilled in the art, a unit device of a Dynamic Random Access Memory (DRAM) consists of one transistor and one information storing capacitor. The storing capacity of the information storing capacitor has a storing capacity of at least 30 fF/cell so as to prevent a soft error operation which is caused by .alpha.-particle.
The more the integration level of the DRAM apparatus is increased, the more the problem for increasing storing capacity in a limited cell space occurs. In order to overcome the problem, the following methods are introduced in the industry based on an expression of (1). EQU C=.di-elect cons..sub.o .di-elect cons..sub.r A/d (1)
where C denotes a storing capacity of a battery, .di-elect cons..sub.o denotes a dielectric constant in vacuum, .di-elect cons..sub.r denotes a dielectric constant of a dielectric thin film, A denotes a surface of a battery, and d denotes a thickness of a dielectric thin film.
The first method is to make the thickness of a dielectric thin film thinner, the second method is to increase the effective surface of a capacitor, and the third method is to use a certain material having a greater dielectric constant.
Among theses methods, the first method has a disadvantage in that it is difficult to adapt to a large scale memory device since the reliability of the thin film is decreased due to the Fowler-Nordheim current in case that the thickness of a dielectric layer is below 100 .ANG..
The second method has disadvantages in that manufacturing process has complexity, and manufacturing cost is increased. That is, although various kinds of capacitor cells, having a three dimensional construction, such as a stack type, a trench type, a fin type, and a cylindrical type are used in 4 MB DRAM and 16 MB DRAM, the above-mentioned capacitor cells can not be effectively used in 64 MB and 256 MB DRAMs.
In addition, the trench type capacitor has a disadvantage in that a leakage current between trenches occurs due to a scaling down operation, and since the cell of the stack type, the fin type, and the cylindrical type have many curved portions and step coverage on the surfaces thereof in order to obtain more storing capacity, it is difficult to perform a photolithography process in the follow-up process, and mechanical strength of the thin film and the cylindrical capacitor is very weak.
The third method is directed to using a high dielectric constant material such as Y.sub.2 O.sub.3, Ta.sub.2 O.sub.5, TiO.sub.2, etc, and recently, a ferroelectric material such as a PZT(PbZr.sub.x Ti.sub.1-x O.sub.3) or a BST(Ba.sub.x Sr.sub.1-x TiO.sub.3 are used. Generally, the ferroelectric material has a self-polarizing characteristic and a dielectric constant from a few hundreds to 1,000. Using this ferroelectric material, it is possible to fabricate a desired thin film having an equivalent oxide thickness of below 10 .ANG. even forming a ferroelectric film having a thickness of a few hundreds.
In particular, the BST among the ferroelectric materials is proper as a high dielectric constant material for a DRAM capacitor since it has a high dielectric constant even in a high frequency as compared to a PZT, and fatigue and aging phenomenon are removed since it is converted to a paraelectric material in accordance with a ratio of Ba/Sr.
Conventionally, a sputtering method, a metal-organic chemical vapor deposition method (MOCVD), a spin coating method, or an aerosol method is used for integrating a high dielectric constant material in a semiconductor apparatus. Sputtering generally involves four steps: ions are generated and directed at a target; the ions sputter target atoms; the ejected (sputtered) atoms are transported to the substrate; and the sputtered atoms condense and form a thin film.
However, the problems occurring while fabricating a BST thin film for use of the DRAM capacitor is that a dielectric constant is decreased since the thickness of a dielectric thin film becomes thin and a more leakage current occurs at a real operation voltage level. In this case, it is possible to prevent the decrease of the dielectric constant through a fabrication process, however, since the phenomenon that the leakage current is decreased and the breakage magnetic field is reduced are the inherent problems of the material, it is the most important problems in really using the BST thin film in the industry.
Therefore, when fabricating the capacitor of the semiconductor apparatus using the BST thin film, the reliability of the semiconductor apparatus is decreased due to a characteristic deterioration of the capacitor.
To improve the above-mentioned problems, a method for improving a dielectric characteristic of the BST thin film which is so bulky and used in a separate device of a ceramic capacitor is disclosed in the industry, which is characterized to add other materials to the BST thin film.
For example, the U.S. Pat. No. 4,058,404 discloses a method for increasing the dielectric constant and for preventing a dielectric variation in accordance with applied voltage. The above method is characterized to insulating using SrTiO.sub.3 of about 18-70%, BaTiO.sub.3 of about 4-7%, Bi.sub.2 O.sub.3 of 2.5-17.5%, and either NiO, Al.sub.2 O.sub.3, or Cu.sub.2 O.
In addition, the U.S. Pat. No. 4,888,246 discloses another method for improving the reliability of the high dielectric constant material and for increasing breakage electric field of a dielectric thin film having a Nitrogen-contained BST by adding Nitrogen into a sputtering gas when depositing a thin film in a sputtering method and the Perovskite structure of AMO.sub.3.

Dielectric thin film and fabrication method thereof


A fluorene compound represented by the following general formula [I]:

An organic luminescent device is a device where a thin film containing a fluorescent organic compound or a phosphorescent organic compound is sandwiched between an anode and a cathode; an electron and a hole injected from the respective electrodes generate an exciton of the fluorescent compound or the phosphorescent compound; and light emitted when the exciton returns to a ground state is utilized.
According to a study of Kodak company in 1987 (Appl. Phys. Lett. 51, 913 (1987)), there has been reported a luminescence of approximately 1000 cd/m2 at an applied voltage of approximately 10 V in a device having a separated-function type two-layer structure using ITO as an anode, a magnesium-silver alloy as a cathode, an aluminum quinolinol complex as an electron transport material and a luminescent material, and a triphenyl amine derivative as a hole transport material. The related patents include U.S. Pat. Nos. 4,539,507, 4,720,432, 4,885,211, and so on.
In addition, it is possible to generate a luminescence from ultraviolet to infrared ones by changing the kinds of the fluorescent organic compound, and in recent years, extensive studies have been made on various kinds of compounds. For instance, such compounds are disclosed in U.S. Pat. Nos. 5,151,629, 5,409,783 and 5,382,477, Japanese Patent Application Laid-Open Nos. 2-247278, 3-255190, 5-202356, 9-202878, 9-227576, and so on.
In recent years, many studies have been made on an application of energy in a triplet state to an EL using phosphorescent compounds as luminescent materials. A high luminous efficiency exhibited by an organic luminescent device using an iridium complex as a luminescent material has been reported by a group at Princeton University (Nature 395, 151 (1998)).
Furthermore, in addition to the organic luminescent device using a low molecular weight material as mentioned above, an organic luminescent device using a conjugated polymer has been reported by a group at Cambridge University (Nature, 347, 539 (1990)). In this report, a luminescence from a single layer is confirmed through film formation of polyphenylene vinylene (PPV) using a coating system.
The related patents of the organic luminescent device using the conjugated polymer include U.S. Pat. Nos. 5,247,190, 5,514,878, 5,672,678, Japanese Patent Application Laid-Open Nos. 4-145192 and 5-247460, and so on.
In this way, a recent progress in the organic luminescent device is remarkable, and characteristics thereof suggest a possibility of applications for various purposes, which enable the luminescent device with a high luminance even at a low applied voltage, a wide variety of luminous wavelengths, a high-speed response, and a thin and lightweight form.
However, an optical output with a higher luminance or higher conversion efficiency is required under the present conditions. In addition, many problems still remain to be solved regarding a durability against a change with time due to a long-term use, deterioration caused by an atmospheric gas containing oxygen, moisture, or the like. Furthermore, it is not still insufficient for solving problems related to the needs for luminescences of blue, green, and red having high color purity when considering the applications to a full color display and the like.

Fluorene compound and organic luminescent device using the same

Abstract: is used to provide an organic luminescent device. Such a device has an optical output exhibiting a high luminance with an extremely high efficiency, and has an extremely high durability.


An electrical mounting device for securing an electrical component or fixture on a wall. The mounting device includes a front plate with an opening therein and a rearward extending portion surrounding the opening. The rearward extending portion may be in the form of a peripheral wall with an open back or a peripheral wall with a rear wall defining an enclosure therein. Bosses with oversize apertures are provided in the plate for accommodating mounting fasteners. Clamp arms are secured rigidly to the ends of the mounting fasteners. The peripheral wall is dimensioned slightly less than the diameter of a standard size hole-saw. The clamp arms can be adjusted to a retracted position for insertion on a wall or to an extended position for securing the electrical mounting device to a wall. The electrical mounting device significantly reduces the time required for mounting an electrical component on a wall.

To improve the lighting or electrical services in their homes, homeowners frequently retrofit their homes with additional electrical devices or light fixtures. Typically this is done by locating an appropriate stud, removing the sheetrock, and installing a standard electrical box or frame member that is secured to the studs with fasteners. This method typically involves replacing or repairing a substantial amount of sheetrock around the newly installed electrical box.
An alternative method includes an electrical box or frame member with flip out arms. In this method, a hole is made in the sheetrock and the electrical box or frame member is pushed through the hole. The hole in the sheetrock must typically be made larger than the box or frame member in order to accommodate the flip out arms as they are passed through the wall. After passing through the sheetrock, the arms are rotated outwards from the box or frame member and fasteners tightened to draw the clamps and box tight against the sheetrock. One problem with this method is that the homeowner must make a hole large enough to accommodate the flip out clamps that extend outward from the sidewalls of the electrical box. Typically the electrician makes a hole with a knife or saw and then enlarges the hole around the perimeter to accommodate each of the clamps. Mounting a conventional box or conventional frame member with rotatable arms therefore typically takes anywhere from 10 to 12 minutes. Given the rates charged by qualified electricians, this excessive installation time can make the installation of additional electrical services very expensive.
What is needed is an inexpensive, mechanically simple electrical box or frame member that can be quickly installed on a wall with minimal effort. Installation of the box should require only a standard size hole-saw for preparing the wall for the box or frame member.

Electrical mounting device front with plate and retractable clamp arms for rapid mounting using hole saw


A magnetoresistive head includes a magnetoresistive element set back from the front end face of the head confronting a record medium for converting changes in a signal magnetic field leaking out from the record track of the record medium into changes in resistance. The magnetoresistive element is connected to a pair of terminals and a sense region is defined between both the terminals. The magnetoresistive element is magnetically coupled to a front flux guide, one end of which is exposed in the front end face of the head, at the other end of the same. The front flux guide is virtually in the form of a rectangle elongated in the direction of the width of the record track of the record medium so as to exceed the sense region of the magnetoresistive element.

1. Field of the Invention
The present invention relates to a thin-film magnetic head for use in magnetic recording and reproducing apparatus such as magnetic disk apparatus and magnetic tape apparatus and, more particularly, relates to a magnetoresistive head for reproducing recorded information on a record medium by the magnetoresistive effect.
2. Description of the Related Art
Recently, with the advancement in magnetic disk apparatus having smaller sizes and increased recording density, there are demands for implementation of contact recording/reproduction during which the head slider has a reduced flying height, i.e., the slider floats slightly above a record medium or the slider contacts the record medium.
When the velocity of a magnetic disk relative velocity to the head is decreased as the diameter of a magnetic disk is reduced, a conventional magnetic inductive head reproduces a deteriorated output. Therefore, a magnetoresistive head (hereinafter briefly referred to as "MR head") which reproduces an output not dependent on the velocity and provides a high power output even when the disk is rotated at low velocity is desired to be developed.
An MR head supplies a constant sense current to a magnetoresistive element to convert changes in magnitude of a signal magnetic field leaked out from the record track of a record medium into changes in resistance and thereby reproduces information recorded on the record medium as changes in voltage. In conventional MR heads, a magnetoresistive element has been exposed on the surface of the head confronting the medium. Therefore, the recording and reproducing through very low flying height or contacting have been very difficult to realize while using a combination of such a head and a metallic record medium because of a short or discharge occurring in between.
Accordingly, the present inventors proposed in Japanese Laid-open Patent Publication No. Hei 5-114119 a flux-guided type magnetoresistive head in such an arrangement that the magnetoresistive element is not exposed on the surface of the head confronting the medium, and a leakage magnetic field from the medium is guided by a flux guide formed of a soft magnetic material to the magnetoresistive element.
The MR head disclosed in the above laid-open patent publication includes a magnetoresistive element of Ni-Fe set back from the front end face of the head confronting a record medium. The magnetoresistive element is provided with a pair of terminals which define a sense region of the magnetoresistive element therebetween, and a constant sense current is adapted to be supplied from one terminal to the other. The MR head further includes a flux guide having one end thereof exposed in the front end face of the head and the other end magnetically coupled to one end of the magnetoresistive element for guiding a magnetic flux from the record medium to the magnetoresistive element.
The flux guide, magnetoresistive element, and terminals are embedded in a nonmagnetic insulating layer and, upper and lower magnetic shields sandwich the nonmagnetic insulating layer. Further, there is defined a gap between the upper and lower magnetic shields for receiving the magnetic flux from the record medium in the front end face of the head.
The sense region of the magnetoresistive element, defined by the pair of terminals, is formed to be larger than the width of the record track on the record medium. The flux guide has, in its plan view, a trapezoidal form, a home plate form, a triangular form, and the like and arranged to be smaller in width than the sense region of the magnetoresistive element.
In the prior art flux guide type MR head, disclosed in the above laid-open patent publication it has been difficult to control magnetic domains because a flux guide smaller in width is used, it has been difficult to control magnetic domains. Consequently, there has been a problem that the reproduced output and reproduced waveform by the magnetoresistive element tend to vary by the multi-domain activities of the flux guide itself.
The above mentioned problem will be described below in detail with reference to FIG. 29. The magnetoresistive element 2 is magnetically coupled to one end of each of a front flux guide 3 and a back flux guide 4. Since the front flux guide 3 is restricted in its length L (a longer length L makes passage of a signal magnetic field .PHI. difficult), the front flux guide 3 has a form whose length L and width W.sub.1 are virtually equal, i.e., a form close to a square.
Accordingly, the easy axis of magnetization, not shown, becomes unstable, and the signal magnetic field .PHI. incoming in the direction of the arrow in the diagram from the record track of a medium circulates as indicated by the arrows in the diagram in the front flux guide 3 and back flux guide 4 and, thereby, circulating magnetic domains partitioned by magnetic walls 5 are formed in each flux guide.
The phenomenon producing a plurality of circulating magnetic domains partitioned by magnetic walls 5 is called a multiple magnetic domain structure. A magnetic domain structure in which the direction of magnetization is aligned with a definite direction, and no magnetic wall is formed, is called a single magnetic domain structure. Magnetic walls, when applied with an external magnetic field, move to minimize the magnetostatic energy. However, it becomes difficult for the magnetic wall 5 to smoothly move when there are pin holes, projections and the like in the front and rear flux guides 3 and 4, and this causes noise.
Thus, in the MR head disclosed in the above laid-open patent publication, the easy axis of magnetization of the flux guide is unstable. Therefore, a multiple magnetic domain structure is produced in the flux guide and, hence, its response to the signal magnetic field .PHI. from the record medium becomes unstable. As a result, there has been such a difficulty that noises are mixed in the reproduced signal.

Magnetoresistive head with a front flux guide and an embedded MR element


A dual encoder (07) has a first shaft (09) being mounted in a housing (16) so as to be rotatable, wherein a first locking mechanism, for locking different rotational positions of the first shaft (09), and at least one first rotation signal generator (26, 27), for generating a signal showing a switchover between two locking positions, are provided at the first shaft (09), and having a second shaft (10) being mounted in the housing (16) so as to be coaxially rotatable, wherein a second locking mechanism for locking different rotational positions of the second shaft (10) and at least one second rotation signal generator (28, 29) for generating a signal showing a switchover between two locking positions are provided at the second shaft (10), wherein both shafts (09, 10) include activation elements (11, 12).

Dual encoders are input apparatuses, which allow users to enter an assigned electrical signal by turning an activation element. Here, dual encoders are characterized in that they do not only include one activation element, for instance a rotary knob or a rotary disk, but two activation elements. Here, both activation elements are connected to a shaft being mounted so as to be rotatable. One rotation signal generator, which is able to directly or indirectly detect a turning of the shaft, is assigned to each shaft. In each instance, the two rotation signal generators then generate an electrical signal after having detected an adjusting movement at the shaft.
Besides, the two shafts are equipped with one locking mechanism in each instance, which mechanism is able to lock the shafts in different rotational positions. In this manner, the signals having been generated by the rotation signal generator can show a switchover between two locking positions by turning the shaft.
For instance, but by no means exclusively, known dual encoders may be used for entering two adjusting values at an appliance, for instance the X value and the Y value in a Cartesian coordinate system, with discrete rates in each instance, with only minor adjusting movements of the hand. From document DE 33 36 746 A1, a simple encoder is known, which is embodied in the manner of a rotary switch. Said encoder has a mechanical locking mechanism, which is able to fix the shaft in different locking positions. Said mechanical locking mechanism has the disadvantage that the mechanical connections of the locking mechanism are subject to relatively high wear, due to which the locking mechanism becomes sluggish or fails completely after a certain running time.


Methods for preparing nanoscale reactions using nucleic acids are presented. Nucleic acids are captured saturably, yet reversibly, on the internal surface of the reaction chamber, typically a capillary. Excess nucleic acid is removed and the reaction is performed directly within the capillary. Alternatively, the saturably bound nucleic acid is eluted, dispensing a metered amount of nucleic acid for subsequent reaction in a separate chamber. Devices for effecting the methods of the invention and a system designed advantageously to utilize the methods for high throughput nucleic acid sequencing reactions are also provided.

This invention is in the field of biotechnology, and relates to methods and apparatus for preparing and performing small scale reactions, particularly small scale cycling reactions and isothermal reactions that use nucleic acid templates.
The original goal of the federally-funded Human Genome Project had been to complete the sequence of the human genome at ten-fold coverage by the year 2005. With dramatic acceleration in pace, a partial draft has recently been presented.
Rather than decreasing, however, the need for rapid, inexpensive DNA sequencing will grow dramatically after the Human Genome Project is completed.
For example, there is growing interest in sequencing the genomes of non-human organisms, including bacteria, plants and animals. More importantly, the burgeoning fields of molecular pathology and pharmacogenomics will require the sequencing of multiple genes from individual patients. Molecular pathology relates to the diagnosis, and often formulation of a prognosis, for human diseases by identifying mutations in particular genes. Pharmacogenomics refers to understanding how allelic differences that exist in all human populations affect the therapeutic response, and susceptibility to side effects, of individuals to drugs. As the need to sequence genes from individual patients grows, so will the demand for point of care sequencing capability. There will need to be a shift from large, centralized, high throughput DNA sequencing facilities that only exist at well-funded academic research centers and genomics companies to small, less complicated, middle-throughput gene sequencing systems that can be installed in the majority of hospitals and clinics. This shift in the market for sequencing technologies will put a premium on reducing the cost of reagents and making the sample processing steps as simple and seamless as possible.
In the late 1970s, Sanger et al. developed an enzymatic chain termination method for DNA sequence analysis that produces a nested set of DNA fragments with a common starting point and random terminations at every nucleotide throughout the sequence. Lloyd Smith, Lee Hood, and others modified the Sanger method to use four fluorescent labels in sequencing reactions enabling single lane separations. This resulted in the creation of the first automated DNA sequencers, which used polyacrylamide slab gels for separations. More recently, fluorescent energy-transfer dyes have been used to make dye sets that enhance signals by 2- to 10-fold and simplify the optical configuration.
Automated fluorescent capillary array electrophoresis (CAE) DNA sequencers appear to be the consensus technology to replace slab gels. Capillary gel electrophoresis speeds up the separation of sequencing products and has the potential to dramatically decrease sample volume requirements. The 96-channel capillary electrophoresis instrument, MegaBACE(trademark), which is commercially available from Molecular Dynamics (Sunnyvale, Calif.), uses a laser-induced fluorescence (LIF) confocal fluorescence scanner to detect up to an average of about 625 bases per capillary (Phred 20 window) in 90 minute runs with cycle times of two hours. Confocal spatial filtering results in a higher signal-to-noise ratio because superfluous reflections and fluorescence from surrounding materials are eliminated before signal detection at the photomultiplier tube (PMT). Accordingly, sensitivity at the level of subattomoles per sequencing band is attainable. Confocal imaging is also particularly important in microchip analysis systems using capillary electrophoresis, where the background fluorescence of a glass or plastic microchip may be much higher than that of fused silica capillaries. Capillary array electrophoresis systems will solve many of the initial throughput needs of the genomic community for DNA analysis. However, present methods for low volume sample preparation still present a significant barrier to increased throughput and reduced cost.
While fluorescent DNA sequencers are improving the throughput of DNA sequence acquisition, they have also moved the throughput bottleneck from sequence acquisition back towards sample preparation. In response, rapid methods for preparing sequencing templates and for transposon-facilitated DNA sequencing have been developed, as have magnetic bead capture methods that eliminate centrifugation. Thermophilic Archae DNA polymerases have been screened and genetically engineered to improve fidelity, ensure stability at high temperatures, extend lengths, and alter affinities for dideoxynucleotides and fluorescent analogs. These improvements have resulted in lower reagent costs, simpler sample preparation, higher data accuracy, and increased read lengths.
The sequencing community has also developed higher throughput methods for preparing DNA templates, polymerase chain reaction (PCR) reactions, and DNA sequencing reactions. Sample preparation has been increasingly multiplexed and automated using 96- and 384-well microtiter, multi-channel pipettors, and laboratory robotic workstations. In general, these workstations mimic the manipulations that a technician would perform and have minimum working volumes of about a microliter, although stand-alone multi-channel pipettors are being used to manipulate smaller volumes.
A typical full-scale sample preparation method for DNA shotgun sequencing on capillary systems begins by lysing phage plaques or bacterial colonies to isolate subcloned DNA. Under some circumstances it may be desirable to PCR-amplify the subcloned DNA insert to exponentially increase its concentration in the sample. Next, exonuclease I (ExoI) and arctic shrimp alkaline phosphatase (SAP) are added to perform an enzymatic cleanup reaction to remove primer and excess dNTPs that interfere with cycle sequencing. ExoI is used to degrade the single-stranded primers to dNMPs without digesting double-stranded products. SAP converts dNTPs to dNPs and reduces the dNTP concentration from 200 xcexcM, as used for the PCR reaction, to less than 0.1 xcexcM for use with fluorescent sequencing. The reaction is performed at 37xc2x0 C. and then heated to 65xc2x0 C. irreversibly denature the ExoI and SAP.
Because PCR amplification can produce excess template DNA for cycle sequencing, the ExoI/SAP treated PCR sample can be diluted five-fold before cycle sequencing. This reduces the concentration of contaminants into a range that causes less interference with capillary electrophoresis analysis. Cycle sequencing reagents are added, typically with fluorescently labeled dye primers or terminators and the reaction is thermal cycled to drive linear amplification of labeled fragments. Finally, after cycling, the samples are post-processed, typically by ethanol precipitation or spin filtration, resuspended in formamide, another denaturant, or water, and the sample is electrokinetically injected into the capillary electrophoresis system.
This workflow has resulted in a dramatic improvement in the performance of the MegaBACE(trademark) system, and similar work flows currently appear to be the methods of choice for other capillary electrophoresis systems as well. Using actual samples from single plaques and colonies of human genomic random subclones or Expressed Sequence Tags (ESTs), this workflow with linear polyacrylamide as a separation matrix has improved the success rate of samples over 200 base pairs from about 60% to 85-90%, and has improved the average read length from about 400 to greater than 600 bases. Furthermore, this method has proven to be quite robust.
While the above sample preparation methods have greatly increased throughout, the cost of reagents remains a major component of the cost of sequencing. Capillary electrophoresis requires only subattomoles of sample, but presently samples are prepared in the picomole range. Reducing the reaction volume will therefore reduce the cost of DNA sequencing and still provide enough material for analysis. However, substantial reductions in reaction volume can only be achieved if satisfactory methods can be developed for manipulating and reacting samples and reagents. Ideally, such a method would be automated and configured to produce multiple samples at one time. Moreover, it would be desirable to integrate such a method as a module capable of interfacing with additional components, such as capillary electrophoresis and a detector for separation and analysis.
Several devices have been designed to aid in the automation of sample preparation. For example, U.S. Pat. No. 5,720,923 describes a system in which small cycling reactions take place in tubes with diameters as small as 1 mm. The tubes are subsequently exposed to thermal cycles produced by thermal blocks to effect the desired reaction. Multiple samples may be processed in a single tube by drawing in small amounts of sample, each of which are separated in the tube by a liquid which will not combine with the sample. Fluid moves through the tubes by means of a pump. These features are incorporated into a system which automatically cleans the tubes, moves sample trays having sample containing wells, and brings the tubes into contact with the wells in the sample trays.
U.S. Pat. No. 5,785,926 discloses a system for transporting small volumes of sample. In this system, at least one capillary tube is used to transport small amounts of sample. A precision linear actuator connected to a computer controlled motor acts as a pneumatic piston to aliquot and dispense liquid using the tube. The sample amount is monitored by an optical sensor that detects the presence of liquid within the capillary segment. The system includes a fluid station containing liquids to be deposited and a positioning device for positioning the transport capillary.
U.S. Pat. No. 5,897,842 discloses a system for automated sample preparation using thermal cycling. In this system a reaction mixture is pumped into a capillary tube. One end of the tube is sealed using pressure from an associated pump while the other end is sealed by pressing the tube against a barrier. The pump also serves to move fluid within the tube. Once the ends are sealed, the tube is exposed to thermal cycles. In this system a robotic transfer device moves the tubes between the sample preparation station where the pump loads the components of the reaction mixture into the tubes and the thermal cycling station.
In the systems discussed above, it is necessary to first mix together a sample, such as DNA template for sequencing, and reagents, prior to introducing the mixture into a reaction chamber. This intermediate mixing step inevitably requires additional reagent and sample handling steps that results in wastage. For example, if separate micropipets are used to dispense sample and reagent into a mixing chamber, small amounts of sample and reagent will be retained in the respective pipets, and reaction mixture will be retained in the mixing chamber. In a high throughput system the cost of this wastage and providing new or properly cleaned pipets and mixing chambers rapidly mounts. Extent of wastage is often exacerbated by the need to dispense relatively large volumes of liquids containing reaction components at low concentration as a strategy to compensate for inaccuracies in dispensing low volumes of higher concentration liquids. Usually, after the reaction mixture is formed, only a small proportion is required for analysis, and the remainder is discarded.
Thus, there exists a need for means by which a biological sample to be analyzed could be introduced into a reaction chamber without the need to first mix the sample with the reagents necessary to effect the reaction.
U.S. Pat. No. 5,846,727 discloses affinity-capture methods wherein template DNA is immobilized inside a glass capillary tube that serves as a reaction chamber for thermal cycling. The capillary is first prepared by immobilizing biotin molecules to the inner surface of the capillary, followed by charging the column with avidin or streptavidin which binds tightly the biotin. Template DNA to be sequenced is covalently linked to a biotin moiety by PCR, and is then exposed to the avidin inside the capillary. This results in immobilization of the template to the capillary wall through a biotin-avidin-biotin linkage. After unbound template is washed away, sequencing reagent is added, and the contents of the capillary are subjected thermal cycling to activate the sequencing reaction. In this manner it is unnecessary to mix template DNA with sequencing reagent prior to loading the capillary.
However, the method just described requires that biotin be linked to the template DNA by PCR, necessitating setting up and carrying out a reaction even before the sequencing reaction. This requisite preliminary step adds to the time and cost associated with acquiring the sequence data. Furthermore, the immobilization of the DNA is effectively irreversible because the biotin-avidin linkage is so strong it can only be broken using agents that denature avidin, a treatment that would also denature any other protein components in a reaction. As a result the template DNA must stay bound to the inner surface of the capillary. Because the DNA is not free in solution, additional time is required for reaction components to diffuse to the walls where they can interact with the DNA. Furthermore, when it is desired to recycle the capillary, it is necessary to remove the template DNA via denaturation of the avidin, washing and then recharging of the avidin in the capillary, all of which add to time and reagent costs.
Thus, there is continued need in the art for methods to introduce molecules into reaction chambers without an initial sample-reagent mixing step, without the need to attach an affinity capture moiety to all the molecules in the sample, and wherein template immobilization is reversible. In this way reagent costs would be minimized and processing speed maximized.
Capillary array electrophoresis systems and capillary electrophoresis microchip analytical systems can detect subattomoles of DNA sequencing reaction products. This extraordinary sensitivity comes at the cost of reduced tolerance, compared to slab gels, for deviations from the ideal amount of template DNA in the sequencing reactions. For example, if there is too little template DNA in the sequencing reaction, there will be poor yield of fluorescently labeled primer extension products. This results in weak signal strength when the reaction products are scanned by the laser. This prevents the software that analyzes the chromatogram from adequately performing spectral separation, resulting in shorter than average sequence read lengths; the reaction will have to be repeated or the sequence information will be lost.
Too much template DNA causes problems as well, due to overloading of the capillary. While there is adequate yield of fluorescently labeled reaction product, if the template is in excess, it competes with sequencing products for entry into the capillary during electrokinetic injection. The presence of the large template DNA molecules can result in an overall reduction, or sudden drop in capillary current, which can manifest itself in a variety of ways. Overloading can cause weak signal strength, late appearance of interpretable fluorescence intensity peaks in the chromatogram, and poor resolution of the reaction products because the fluorescence emission is broad and diffuse. All these effects lead to shorter reads and lower sequencing data quality.
The problem of overloading is typically solved by either diluting the sequencing reaction, or carefully titrating the amount of template DNA introduced into the sequencing reaction. While both these solutions are simple in principle, the former requires repeating the analysis of the reaction, and the latter is difficult to implement using conventional means in a high-throughput system. These means include detecting, and comparing to standard concentration curves, the quantity of fluorescent dye that binds DNA in a sample, or measuring the absorbance of ultraviolet light at 260 nm wavelength, which can be converted into an absolute measure of DNA concentration. Thus, there is continued need in the art for methods to titrate the quantity of template DNA for sequencing reactions to be analyzed using high-throughput capillary electrophoresis systems, where minimizing cost and maximizing speed are crucial.
There is an additional need for an automated system that is able to perform small-scale thermal cycling reactions in a highly parallel manner. The system should allow for rapid preparation of cycling reactions with minimal consumption of reagents. The combination of reducing the amount of reagents required for a reaction and reducing the time required for a reaction will greatly reduce the overall cost of reparation of cycling reactions.
It is, therefore, an object of the present invention to provide novel methods for introducing small amounts of nucleic acid, such as template DNA to be sequenced, into a reaction chamber in a manner that obviates prior mixing of the nucleic acid with reagents to generate a reaction mixture.
It is a further object of the present invention to provide methods useful for introducing small amounts of nucleic acid into a reaction chamber without use of affinity capture moieties attached to the nucleic acid or reaction chamber.
It is a further object of the present invention to provide methods of introducing small amounts of nucleic acid into a reaction chamber without irreversible binding of nucleic acid to the wall of the reaction chamber.
It is yet another object of the present invention to provide methods useful for obtaining predetermined approximate quantities of nucleic acid for use in a reaction, such as template DNA to be sequenced, without the need to determine the concentration of the nucleic acid in the solution from which the DNA was drawn. It is a particular object of the invention to provide methods to titrate the quantity of template DNA for use in sequencing reactions that are to be analyzed using high-throughput capillary array electrophoresis systems, where minimizing cost and maximizing speed are crucial.
It is a further object of the invention to provide an automated system that is able to perform small-scale thermal cycling reactions in a highly parallel manner.
In accordance with this invention, a method is provided by which predetermined, reproducible amounts of nucleic acid are captured from solutions having wide variation in nucleic acid concentration directly, yet reversibly, onto a surface of the reaction chamber, either for submicroliter reaction directly therein or for metered elution into a second chamber for subsequent use. In accordance with other aspects of the invention, apparatus and systems useful for performing the inventive methods are provided.
The present invention is based, in part, upon the novel use of the saturable, yet reversible, binding of nucleic acids to the surface of certain materials. This reproducible, saturable, yet reversible binding is used to control the mass of nucleic acid delivered as template to a subsequent reaction, without a required antecedent determination of the concentration of nucleic acid in the solution from which the nucleic acid is to be captured. In particular embodiments, the internal surface of a capillary is used to effect nucleic acid capture, permitting nucleic acid template to be captured directly in the chamber in which subsequent reaction is to be performed.
Thus, in a first aspect, the invention provides a method of introducing into an enzymatic reaction a predetermined approximate mass of nucleic acid, comprising: saturably capturing, directly onto an interior surface of a chamber in which said enzymatic reaction is to be performed, a predetermined approximate mass of nucleic acid from an excess thereof, and then removing the excess.
The methods of the present invention are articularly useful in submicroliter DNA sequencing reactions. Thus, in another aspect, the invention provides a method of performing a DNA sequencing reaction, comprising: immobilizing template DNA directly on a substrate, and then contacting the template DNA with a reaction mixture that effects the DNA sequencing reaction. In related aspects, the invention further provides a product of a DNA sequencing reaction effected by the above-described method, and a DNA sequence derived from the product of the DNA sequencing reaction.
In another aspect, the invention provides a method of verifying the sequence of template DNA in solution, wherein the solution has been, or is desired to be, contacted to a first substrate as part of a spatially addressable array, comprising: immobilizing the template DNA directly on a second substrate, wherein said template DNA is immobilized by contacting the second substrate with the solution of template DNA for time sufficient for the DNA to become immobilized, and then contacting said template DNA with a reaction mixture that effects said DNA sequencing reaction, wherein the composition of the template DNA solution to be contacted to said first and second substrates is essentially identical.
The invention further provides systems that advantageously utilize the capillary-based embodiments of the present invention to effect high throughput reaction. In one embodiment of this aspect of the invention, the system uses a capillary cassette comprised of a number of capillary tube segments arranged in parallel alignment. The tube segments extend through a substrate and are generally positioned with uniform spacing. The capillary cassette may be used both to meter reagents and as a reaction chamber in which the reaction is conducted.
The system of the present invention is useful for the preparation of sequencing reactions, but may also be used in highly parallel preparation of cell lysates, plasmid extraction, polymerase chain reactions, ligase chain reactions, rolling circle amplification reactions, screening compound libraries for drug discovery or compound activity, protein digestion/sequencing, ELISA, radioimmunoassays and other chemical or biochemical reactions or assays.

Methods and apparatus for template capture and normalization for submicroliter reaction


A high-frequency module includes a stiffener (a support substrate), a resin base member of which one surface is fixed to the stiffener, a first conductive pattern formed on said one surface of the resin base member, a second conductive pattern formed on the other surface of the resin base member for constituting a waveguide in combination with the first conductive pattern to pass a high-frequency signal through the resin base member and including a window for allowing the high-frequency signal to pass therethrough, a cap for covering a semiconductor element and for absorbing or reflecting the high-frequency signal, an adopter (a waveguide tube) fixed onto the second conductive pattern such that one open end thereof surrounds the window, and an antenna fixed to the other open end of the adaptor.

1. Field of the Invention
The present invention relates to a high-frequency module.
2. Description of the Related Art
An in-vehicle radar device to be mounted on an automobile uses a high-frequency module which is operated in a millimeter wave range. The in-vehicle radar is widespread for the purpose of measuring a distance to an automobile which is running ahead, for instance. An example of the in-vehicle radar device is disclosed in Patent Literature 1.
In the Patent Literature 1, an active element such as a monolithic microwave integrated circuit (MMIC) is mounted on one surface of a metal substrate via a circuit substrate, and an antenna for transmitting and receiving a high-frequency signal is provided on the other surface of the metal substrate. In this structure, it is necessary to form a hole in the metal substrate so as to constitute a waveguide tube for guiding the high-frequency signal from the antenna to the active element. According to the Patent Literature 1, manufacturing time for the high-frequency module is reduced by forming the hole as the waveguide tube on the metal substrate while the circuit substrate is attached to the metal substrate.
Meanwhile, Patent Literature 2 discloses an FM radar module configured to connect an MMIC to an antenna so as to carry a high frequency by use of a pin.
However, forming the hole in the metal substrate requires a high cost. Accordingly, formation of the through hole serving as the waveguide tube in the metal substrate as disclosed in Patent Literature 1 incurs an increase in manufacturing costs of the high-frequency module.
(Patent Literature 1) Japanese Unexamined Patent Publication No. 2003-86728
(Patent Literature 2) Japanese Unexamined Patent Publication No. 8(1996)-114667


A readout circuit for use in an image sensor includes a sense amplifier circuit coupled to a bitline to sense analog image data from a pixel cell of the image sensor. An analog to digital converter is coupled to the sense amplifier circuit to convert the analog image data to digital image data. A ramp generator circuit is coupled to generate a first ramp signal. The analog to digital converter is coupled to generate the digital image data in response to the analog image data and the first ramp signal. A first capacitive voltage divider is coupled to the ramp generator. The first capacitive voltage divider is coupled to reduce an output voltage swing of the first ramp signal coupled to be received by the analog to digital converter to reduce noise in the first ramp signal.

Field of the Disclosure
The present invention relates generally to image sensors. More specifically, examples of the present invention are related to circuits that read out image data from image sensor pixel cells.
Background
Image sensors have become ubiquitous. They are widely used in digital cameras, cellular phones, security cameras, as well as, medical, automobile, and other applications. The technology used to manufacture image sensors, and in particular, complementary metal-oxide-semiconductor (CMOS) image sensors, has continued to advance at a great pace. For example, the demands for higher resolution and lower power consumption have encouraged the further miniaturization and integration of CMOS image sensors.
In CMOS image sensors, performance factors such as horizontal noise (h-noise), circuit power supply rejection ratio (PSRR), power consumption, etc., have been key parameters in which efforts have been made for improvement in recent years. Since human vision is especially sensitive to horizontal banding/noise in images, enormous efforts have been made to reduce this type of noise. Specifically, with regard to the most popular image sensor readout structures, column-wise analog to digital converters tend to generate large amounts of horizontal noise because the ramp generators are row-wise signals. Consequently, any noise in the ramp generator ramp outputs lead to different row-by-row readout performance. Similarly, due to the nature of single-ended ramp generators, power supply rejection ratio is also an important factor to be considered. An insufficient power supply rejection ratio will cause image horizontal banding due to ripple in the analog power supply.
Another concern with image sensor chips is the analog power consumption. A typical analog power supply for a state-of-the-art image sensor is around 2.8 V. This high analog VDD voltage is necessary in order for pixels to output full well signals. However, with image pixels being developed in a more aggressive fashion, smaller size pixels also have a lower full well requirement. As a result, compared to previous image pixels, a ˜1 V, ˜500 mV, or an even lower pixel output range is sufficient. Under these circumstances with lower pixel output ranges, a lower analog VDD supply voltage is a trend in future image sensor designs where power consumption is greatly reduced. Accordingly, readout circuitries also need to accommodate this lower analog VDD supply voltage trend, while still maintaining the same low noise performance.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.

Ramp generator for low noise image sensor


A dunnage support bar for supporting and retaining dunnage is formed with a number of longitudinal extending semicircular indented ribs for strengthening the bar and resisting bending. The dunnage bar has a T-shaped channel for slidingly receiving the dunnage, which supports an article to be transported. The bar is formed of at least two members, one folded within another, so as to affix the members together and prevent relative motion.

1. Technical Field
The present invention relates generally to material handling systems, and more particularly to a dunnage bar for use in a dunnage support structure.
2. Discussion
Various articles must be transported in almost every industry. For example, in the automobile industry, parts and components must be shipped from vendors to the automobile manufacturers. Many larger automotive components and subassemblies are shipped in custom designed rack assemblies, or dunnage support structures. These dunnage support structures include a horizontal metal base frame, two vertical end frames, and pairs of vertical support racks located at opposite ends of the horizontal frame. The vertical racks retain dunnage support bars which extend horizontally between a pair of the racks. The dunnage support bars are generally constructed of metal and may have a T-shaped channel for receiving an appropriately formed portion on a dunnage detail or member. The dunnage member slides onto a dunnage support bar and is locked in place longitudinally by dunnage stops which may be bolted or otherwise removably secured to the dunnage bar. The dunnage members are generally plastic or rubber and are formed to uphold and cushion the part or component from potentially damaging impacts while being transported.
The elements of the dunnage support structure are generally of a standard configuration, while the dunnage members are specifically designed for each particular type of part or component transported. The entire dunnage support structure is generally constructed to be disassembled and collapse after the parts have been shipped, in order to return the dunnage support structure to the vendor for use in a subsequent shipment.
Dunnage bars have generally been constructed of extruded aluminum, although steel has also been used. However, aluminum dunnage bars are difficult and costly to manufacture. In view of the fact that aluminum is not only relatively costly, but also readily recyclable, many aluminum dunnage bars are subject to theft. On the other hand, steel dunnage bars are generally heavy and are susceptible to corrosion. The steel bars are also generally not sufficiently flexible, and yield to permanent deformation under relatively light loads.
Accordingly, it is desirable to provide a dunnage bar which is strong, lightweight, abrasion and corrosion resistant, and less susceptible to theft. Furthermore, it is desirable to provide a dunnage bar which is resilient and can accept a wide variety of loads and impacts without permanent deformation. Other factors which affect the design of such a desirable dunnage support bar are size, cost, ease of manufacture, and protection for the articles to be shipped.


A zoom lens comprises, in the following order from the object side to the image side, a positive first lens unit, a negative second lens unit, which moves during zooming, a positive third lens unit, and a positive fourth lens unit, which moves during zooming. The first lens unit includes a negative lens subunit and a positive lens subunit. The negative lens subunit includes at least two negative lenses each having a concave surface facing the image side and at least one positive lens arranged from the object side. The positive lens subunit includes at least one biconvex positive lens, a negative lens and at least two positive lenses arranged from the object side, or at least one biconvex positive lens, a cemented lens composed of a negative lens and a positive lens and at least one positive lens arranged from the object side.

1. Field of the Invention
The present invention relates to a zoom lens and an image pickup apparatus equipped with the same. The present invention can be suitably applied to an electronic camera such as a video camera or a digital still camera, a film camera, and a broadcast camera etc.
2. Description of the Related Art
In recent years, image pickup apparatuses (or cameras) such as video cameras, digital still cameras and surveillance cameras using a solid state image pickup element are required to have many functions and to be small in their entire size.
In accordance with such requirements, optical systems (image pickup optical systems) used in such cameras are required to be constructed as zoom lenses that are small in size, have a wide angle of view while having excellent optical performance.
When a color separating optical system such as a prism or filter is used in an image pickup apparatus, the color separating optical system is provided in its image side end portion. Accordingly, zoom lenses used in such image pickup apparatuses are required to have back focus equal to the optical path length of the color separating optical system.
As a zoom lens that meets the above requirements, a four-unit zoom lens having a positive first lens unit, a negative second lens unit, a positive third lens unit and a positive fourth lens unit arranged in the mentioned order from the object side to the image side is known. Note that a lens unit or element having a positive optical power or positive refractive power is referred to as a positive lens unit or element in this specification, and a lens unit or element having a negative optical power or refractive power is referred to as a negative lens unit or element.
One known type of such a four-unit zoom lens is what is called a rear-focus four-unit zoom lens in which the second lens unit is moved to effect zooming and the fourth lens unit is moved to correct image plane variations caused during zooming and to effect focusing.
There have been disclosed various rear-focus four-unit zoom lenses that have the first lens unit including a negative front subunit and a positive rear subunit arranged in the mentioned order from the object side to the image side to achieve a wide angle of view (see Japanese Patent Application Laid-Open Nos. H11-287952 and H11-287954).
A five-unit zoom lens having a positive first lens unit, a negative second lens unit, a positive third lens unit, a positive fourth lens unit and a positive fifth lens unit arranged in the mentioned order from the object side to the image side is also known as a zoom lens that meets the above described requirements.
In a known type of such a five-unit zoom lens that has a relatively wide angle of view, the second lens unit and the fourth lens unit are moved for zooming, and the fourth lens unit is moved for focusing (see U.S. Pat. No. 5,694,252 and Japanese Patent Application Laid-Open No. 2002-365539).
When a zoom lens is constructed as a rear focus system, the size of the entire lens system can be made smaller, focusing can be made faster and short distance shooting can be made easier as compared to zoom lenses in which focusing is effected by the first lens unit.
On the other hand, however, the rear focus zoom lens suffers from larger aberration variations during focusing.
It is difficult to achieve a wide angle of view and a high zoom ratio while achieving excellent optical performance throughout the entire zoom range.
To achieve a wide angle of view and a high zoom ratio in a rear-focus zoom lens while achieving excellent optical performance throughout the entire zoom range, it is necessary to design the configuration of each lens unit, especially the configuration of the first lens unit appropriately.
In addition, to provide back focus long enough to allow to provide a color separating optical system on the image side of the zoom lens, it is necessary to design the refractive power arrangement and the lens configuration in each lens unit appropriately.
In particular, in the case of the above described types of four-unit zoom lenses and five-unit zoom lenses, it is very difficult to enlarge the angle of view and increase the zoom ratio while achieving excellent optical performance throughout the zoom range unless the lens configuration of the first lens unit is appropriately designed.

Zoom lens and image pickup apparatus equipped with same