Showing papers on "Tantalum capacitor published in 1993"

High dielectric constant capacitor and method of manufacture

Abstract: A high storage capacity capacitor for a semiconductor structure includes a barrier layer formed on a polysilicon electrode, a lower electrode, a dielectric layer, and an upper electrode. The dielectric material is formed of a high dielectric constant material such as BaSrTiO 3 . In order to protect the barrier layer from oxidation during deposition of the dielectric layer and to provide a smooth surface geometry for depositing the dielectric layer, conducting or insulating spacers are formed on the sidewalls of the barrier layer and lower electrode. A smooth dielectric layer can thus be formed that is less susceptible to current leakage. In addition, the insulating spacers can be formed to completely fill a space between adjacent capacitors and to provide a completely planar surface.

Ultrathin Tantalum Oxide Capacitor Dielectric Layers Fabricated Using Rapid Thermal Nitridation prior to Low Pressure Chemical Vapor Deposition

Abstract: We describe the formation of ultrathin tantalum oxide capacitors, using rapid thermal nitridation of the storage-node polycrystalline-silicon surface prior to low pressure chemical vapor deposition of tantalum oxide. The amorphous tantalum oxide film is deposited on the nitrided polysilicon surface using penta-ethoxy-tantalum [Ta(OC 2 H 5 ) 5 ] and oxygen (O 2 ) gas mixture at 410 o C. The films are annealed at 600-900 o C in dry O 2 . Densification of the as-deposited film by annealing in dry O 2 is indispensable to the formation of highly reliable ultrathin tantalum oxide capacitors. During this densification, CH 4 and H 2 O desorb from the as-deposited film, and the film crystallizes into an orthorhombic structure

Storage capacitor with a conducting oxide electrode for metal-oxide dielectrics

Abstract: A capacitor having a high dielectric constant and method of making the same is disclosed. The capacitor comprises a bottom electrode comprising a conductive oxide deposited upon a substrate by chemical vapor deposition. A dielectric layer having a high dielectric constant is deposited upon the conductive oxide. Lastly, a counter electrode is formed upon the dielectric layer.

Method of making a capacitor for an integrated circuit

Abstract: A method is provided for forming a capacitor structure for a memory element of an integrated circuit. The method comprises providing a first conductive electrode, forming a layer of a first dielectric material thereon, opening a via hole through the dielectric layer, providing within the via opening a capacitor dielectric having a higher dielectric strength than the first dielectric, the capacitor dielectric contacting the first electrode, planarizing the resulting structure and then forming a second conductive electrode thereon. Preferably, when the second dielectric comprises a ferroelectric dielectric material, sidewalls of the via opening are lined with a dielectric barrier layer to provide diffusion barrier between the ferroelectric and first dielectric layer. Advantageously, planarization is accomplished by chemical mechanical polishing to provide fully planar topography. The method provides a capacitor of a simple, compact structure which may be integrated with CMOS, Bipolar and Bipolar CMOS processes for submicron VLSI and ULSI integrated circuits.

Method of fabricating capacitor element in super-LSI

Abstract: A capacitor element of a semiconductor device used for a super-LSI is formed by the steps including (a) removing a natural oxide film on a surface of a lower electrode of polysilicon, (b) forming on the surface of the lower electrode an impurity-doped tantalum oxide film, and (c) forming an upper electrode with at least a bottom thereof constituted by titanium nitride. The steps may further include (d) nitriding the surface of the lower electrode after the removal of the natural oxide film, and (e) densifying the tantalum oxide film by way of a high temperature heat treatment after the formation of the tantalum oxide film. In this way, it is possible to reduce thickness of a capacitive insulating film and to form the capacitor element in which the leakage current characteristics are improved.

Stacked type solid electrolytic capacitor

Abstract: A stacked type solid electrolytic capacitor has a plurality of single plate capacitors each constituted by a dielectric oxide film, a solid electrolytic film and a negative electrode layer sequentially laminated on a surface of a positive electrode member having a positive electrode section. A metal spacer which has a thickness corresponding to each of spaces between the positive electrode sections is placed in each of the spaces. The metal spacers and the positive electrode sections are mechanically and electrically interconnected by welding. The invention may be embodied in a stacked electrolytic capacitor of a lead type or that of a chip type. The invention provides capacitor in which the size is reduced and the capacity is increased, the possibility of deterioration in electrical characteristics during the fabrication process is eliminated, and the process of fabrication is made easy.

Transistor and a capacitor used for forming a vertically stacked dynamic random access memory cell

Abstract: A transistor and a capacitor is used to provide, in one form, a dynamic random access memory (DRAM) cell (10). The capacitor of cell (10) lies within a substrate (12). The capacitor has a first capacitor electrode (16) and a second capacitor electrode (20). A dielectric layer (18) is formed as an inter-electrode capacitor dielectric. A first transistor current electrode (36) is formed overlying and electrically connected to the first capacitor electrode (16). A channel region (38) is formed overlying the first transistor current electrode (36). A second transistor current electrode (40) is formed overlying the channel region (38). A conductive layer (30) is formed laterally adjacent the channel region (38) and isolated from the substrate (12) by dielectric layers (22 and 28). A conductive layer (30) functions as a gate electrode for the transistor and a sidewall dielectric (34) functions as a gate dielectric. The combination of a cylindrical dual-sidewall surface area capacitor for a large capacitance, along with a vertical transistor physically overlying the capacitor, forms a very dense and efficient DRAM structure.

Monolithic high-voltage capacitor

Abstract: s7 A high voltage capacitor (10) structure for integrated circuits or the like. The capacitor includes a provision for equalizing charge when multiple capacitors are series coupled. Charge is equalized by a SiN layer (18) overlaying, and in contact with one terminal (13) of, the capacitor. A ground ring (17) surrounds the capacitor structure and is also overlayed by, and in contact with, the SiN layer.

The Impact of High Energy Density Capacitors with Metallized Electrode in Large Capacitor Banks for Nuclear Fusion Applications

Abstract: : Power supplies for Inertial Confinement Fusion (ICF) lasers require large capacitor banks. As capacitor bank size increases, reliability, expressed as Mean-Time-Between Failures (MTBF) is reduced, for a given capacitors design. Metallized electrode capacitors exhibit more predictable failure characteristics than traditional foil designs, thus increasing MTBF for some applications. In addition, their soft failure mode gives facility operators flexibility to schedule capacitor bank maintenance. Experience with the design and testing of a metallized electrode capacitor for a 13 MJ bank is presented. Weibull statistics are used to predict performance on the 13 MJ bank, and on a proposed 250 MJ facility. While the Beamlet capacitor data is specific to Aerovox capacitor part number KM223YW215D01, much of the information is applicable to high voltage metallized electrode capacitors in general.

Semiconductor device having stacked type capacitor

Abstract: A DRAM providing a capacitor capacity sufficient for maintaining stable storage of data even if elements are further reduced in size in accordance with high density integration of semiconductor devices is disclosed. The DRAM has its capacitor upper electrode formed of an upper layer and a lower layer, and its capacitor lower electrode formed to surround the lower layer of the capacitor upper layer, and the upper layer of the capacitor upper layer formed to cover the upper surface and both sides of the capacitor lower electrode. Thus, a capacitor capacity is tremendously increased as compared to a conventional one in the same plane area as the conventional one.

Substrate having a built-in capacitor and process for producing the same

Abstract: In a substrate having built-in capacitor which is incorporated in and united with an insulator, the capacitor has a dielectric layer made of a silicon nitride-based ceramic containing silicon carbide in an amount of from 13 to 30% by weight.

Cylindrical metal fibers made from tantalum, columbium, and alloys thereof

Abstract: A method of making a tantalum capacitor of improved specific capacitance (and volumetric efficiency) is described. Short tantalum fibers are precipitated out of a carrier liquid to form a felt, or tumbled to form fiber containing particles, and in either case subsequently bonded so as to form a felt or particles containing the fibers in random orientation in substantially non-aligned array. These particles or felt are heated to bond the fibers together, purify and (optionally) cylindricalize them. The felt or particles can be processed in conventional fashion thereafter to form the capacitor. Cylindricalized fibers and pellets of increased surface area are also described.

Multilayer electrolytic capacitor

Abstract: PURPOSE:To provide the construction for a capacitor by which the frequency characteristics can be realized in order to obtain an excellent acoustic characteristics of acoustic device, etc., in a multilayer electrolytic capacitor. CONSTITUTION:Tabs 2a and 2b for fitting a lead are prepared on a single-board capacitor element 1 for stacking, and a multi-layered capacitor element is joined with integrated leads 3a and 3b, then the leads 3a and 3b comprising an anode and a cathode are closed to each other and connected with the connection terminals. By shortening the lead-out distance of the lead from the element 1 and further making the integrated leads 3a and 3b close to each other, the resistance in an equivalent circuit and the inductance can be reduced to the minimum, resulting in a capacitance having an excellent high-frequency characteristics.

Thermal aging effects on the electrical properties of film and ceramic capacitors

Abstract: Experiments are carried out to evaluate film and ceramic capacitors for potential use in high temperature applications. The capacitors are characterized in terms of their capacitance stability and dielectric loss in the frequency range of 50 Hz to 100 kHz at temperatures of 20/spl deg/C to 200/spl deg/C. DC leakage current measurements are also obtained as a function of temperature. The effects of thermal stressing, in air and without electrical bias, on the properties of the capacitors are determined as a function of thermal aging up to 12 weeks. The results indicated that short-term aging has minimal influence on the dielectric properties of both the teflon and ceramic type capacitors.

Tantalum capacitor chip, process for making the same and tantalum capacitor incorporating the same

Abstract: A process is provided for making a tantalum capacitor chip which includes a tantalum chip body as well as an anode wire partially inserted into and partially projecting from the chip body. The process comprises the steps of compacting an initial divided amount of tantalum powder into an initial mass portion which is dimensionally smaller than the chip body, and compacting at least one additional divided amount of tantalum powder with the initial mass portion into the chip body. The capacitor chip thus obtained may be enclosed in a resin package to provide a surface mounting type tantalum capacitor.

Feed-through type capacitor, electronic device using it, and its mounting method

Abstract: PURPOSE: To provide a through type capacitor which is lessened in the occurrence of structural defects and can be applied to large-current circuits, electronic devices using the capacitor, and a method for mounting the capacitor. CONSTITUTION: The title capacitor 10 has a dielectric 2, conducting terminals 3, electrodes 4A and 4B for capacitor, terminal 4C for capacitor, internal electrode 5, a short-circuiting conductor 6 which short-circuits the terminals 3 with each other and has an equivalent series resistance smaller than that of the electrode 5. Since the conductor 6 is separately provided on the side face of the dielectric 2 without increasing the thickness of the electrode 5, the occurrence of structural defects becomes smaller. In addition, since the equivalent series resistance of the conductor 6 is smaller than that of the electrode 5, the heat generation of the capacitor 10 can be prevented and the capacitor 10 can be applied to large-current circuits even when the current to which the capacitor 10 is applied is large. COPYRIGHT: (C)1994,JPO

Capacitor, especially electrolytic capacitor

Abstract: A capacitor, especially an electrolytic capacitor (10) having an anode (12), cathode (20) and dielectric (14), is described, in the case of which the dielectric (14) consists of at least one layer (18) whose dielectric constant is greater than the dielectric constant of the corresponding oxide (16) of the respective carrier material of the layer.

Manufacturing process of electrolytic capacitors with conductive polymer cathode layer and low current leakage

Abstract: Process for manufacturing electrolytic capacitors with conductive-polymer precathode and low leakage current, comprising the steps of: - producing an anode (2) made of a metal chosen from aluminium and tantalum which is treated in a first electrolytic bath in order to cover it with a thin oxide layer (4) constituting the dielectric of the capacitor; - depositing a conductive-polymer layer (6) onto this dielectric layer (4), by successive treatments in a second, monomer bath and then in a third bath containing the oxidising agent plus, in some cases, the dopant (if the dopant is different from the oxidising agent), this conductive-polymer layer forming the precathode of the capacitor; - reoxidising the anode covered with the conductive polymer by treatment in a fourth electrolytic bath; - fixing a cathode to the precathode; characterised in that the fourth bath is of a different chemical nature to the first and contains ions which are harmless with respect to the conductive polymer.

東長原工場におけるタンタルの製造（昭和キャボットスーパーメタル（株））

Abstract: This plant is a joint venture between. Cabot Co., Ltd. U.S.A. and Showa Denko K.K. and was established in March 1972. Tantalum electrolytic capacitors, which constitute an indispensable element of electronic circuits for high-reliability equipment, have been finding wider applications in recent years. Our capacitor-grade tantalum powder and wire have been receiving favors from respective tantalum capacitor manufactures for many years. We have also established an integrated mill product production system covering production of high purity tantalum ingot by 600 kW EMB furnace, processing of the ingot into mill products such as sheet, rod and tube and processing assembly of the mill products into parts and equipment. We produce all these products at Higashinagahara-plant.

Dielectric and capacitor employing it

Abstract: PURPOSE:To obtain a dielectric having high permittivity and low leak current and dielectric loss, and a capacitor employing the dielectric. CONSTITUTION:Al is sputtered on a glass substrate 1, for example, to form an underlying electrode 2. Sputtering is then conducted in an atmosphere containing nitrogen gas using Ta (tantalum) containing Y (yttrium) as a target thus forming an alloy film 3 of Y-Ta-N composition. The alloy film 3 is then masked and subjected to anodic oxidation thus forming a dielectric film 4 of Y-Ta-O-N composition and an upper electrode 5 is formed thereon by sputtering. The content of Y is set in the range of 1-30% and the dielectric film 4 has high permittivity and low leak current and dielectric loss. A capacitor having excellent characteristics can be obtained using this dielectric.

Tantalum electrolytic capacitor employing polypyrrole as solid electrolyte

Abstract: The conventional tantalum electrolytic capacitor is made by anodically oxidizing sintered porous tantalum metal powder to form tantalum oxide film, followed by precipitating manganese dioxide by thermal decomposition of the tantalum oxide film soaked in manganese nitrate solution. The electrical conductivity of manganese dioxide is as low as 10−2 to 10−1 S/cm, and manganese dioxide is poor in its electrical property, in particular, the high-frequency characteristic. In this paper, a precoating layer with a slightly higher resistance is used. The polypyrrole film is deposited by electrolytic polymerization using the precoating layer as the anode. It is found that the capacitor with polypyrrole formed by chemical oxidative polymerization has superior electrical properties compared to the capacitor formed by using manganese dioxide instead of a precoated layer. Using hydrogen peroxide as the oxidizer for chemical oxidative polymerization, polymerization of pyrrole can be achieved even inside the sintered body and the electrical conductivity and thermal stability of the polymer were excellent. The resultant capacitor has excellent electrical and temperature characteristics, its lifetime is long, and it can be surface-mounted.

Multiple port thin film capacitor

Abstract: A capacitor element for an integrated circuit comprises a thin layer of dielectric material laminarly disposed between first and second layers of electrically conductive material. Each of the layers has n sides, where n is an even intergergreater than four. Preferably, each layer of the capacitor, and therefore the capacitor itself, is shaped as an equiangular polygon. Although, the capacitor may be configured as a hexagon, a decagon, etc., an octagonal configuration is preferred. By eliminating the 90 feed bend, substantial reductions in discontinuity reactances are obtained. The capacitor element may be provided as an element of a hybrid or a monolithic circuit. When the capacitor element is employed as an element of a microwave circuit, the first conductive layer is deposited on a substrate of a semi-insulating material such as gallium arsenide. The dielectric layer may be formed from silicon nitride, silicon dioxide, silica, or tantalum pentoxide, depending upon the specific capacitance required by the application.

Conduction aging test in manufacture of capacitor

Abstract: PURPOSE:To prevent good capacitors from being destroyed due to the self- ignition of adjacent defective ones in aging tests for capacitors such as tantalum capacitors. CONSTITUTION:Capacitors A are manufactured with each placed between a pair of the left and right side frames 2 and 3 of a lead frame 1 and with its lead terminals A1 and A2 integrally coupled with the side frames 2 and 3, respectively. The lead terminal A1 of each capacitor A is cut off midway and the resulting gap is filled in with low melting point alloy 11 such as solder. In this state a test voltage is applied between the side frames 2 and 3.

Solid electrolytic capacitors and process for producing the same

Abstract: A solid electrolytic capacitor having a solid electrolyte layer, which layer comprises an electrically conductive thermoplastic organic polymer complex having an electric conductivity of 0.1 Scm -1 or more and a glass transition temperature of -100 to 150°C formed on a valve metal foil through a dielectric film. A small and larege-capacity solid electrolytic capacitor having excellent highfrequency characteristic and long-term stability is provided.

Lead frame material for tantalum capacitor and its manufacture

Abstract: PURPOSE:To provide a lead frame material for a tantalum capacitor excellent in thermal peeling resistance and capable of showing good solder wettability over a long period and its manufacture. CONSTITUTION:An intermetallic compound layer of tin and copper with 0.2 to 27mum thickness if formed between a base metal of nickel or a nickel allay and a tin or solder plated layer. The above lead frame material can be manufactured by forming a copper substrate plated layer of 0.1 to 1.0mum on the base metal; tin or solder plated layer is furthermore formed on the above copper substrate plated layer; and after that, it is subjected to reflowing treatment or is applied with hot-dip coating of tin or solder.

An X-ray diffraction study of pyrolytic manganese dioxide

Abstract: The thermal decomposition of aqueous manganese nitrate has been studied under a range of experimental conditions to scientifically assess the pyrolysis processes employed by the tantalum capacitor industry. The crystalline phase and form of the manganese oxides produced are compared by X-ray diffraction and scanning electron microscopy. Those experimental conditions producing materials with the lowest resistivity are identified. The technological significance of the decomposition process is discussed and initial results from a novel pyrolysis technique are presented.

Voltage stabiliser for l.v. DC networks, especially in cars - has electrolytic capacitor in series with resistor and diode to ensure correct polarity with time delay switch

Abstract: A device for stabilising the voltage on l.v. DC networks with consumers of variable current demand uses filter capacitors of high capacitance. A resistance limiting the initial charging current and a diode ensuring the correct polarity are connected in front of an electrolytic capacitor. The resistance and diode can be short-circuited after a certain time delay by means of a switch following charging of the correct polarity. Parallel to the electrolytic capacitor is at least one non-electrolytic capacitor of low capacitance and also a peak-topping Zener diode. Across the electrolytic capacitor and the rectifier is connected an LED which illuminates when the polarity of the connection is incorrect. ADVANTAGE - Easy to assemble, ensures long life for the electrolytic capacitors and suffers no damage from incorrect polarity.

Semiconductor DRAM with stacked capacitor - has upper capacitor electrode covering top surface and both side surfaces of lower capacitor electrode

Abstract: The top capacitor electrode has coupled top and bottom layers, while a lower capacitor electrode (7) surrounds the top capacitor electrode lower layer. Between the top and bottom capacitor electrode is a capacitor insulating film (8). The top capacitor electrode top layer (9b) is so shaped that it covers the top face and both side faces of the bottom capacitor electrode. Pref. the bottom capacitor electrode has two electrode layers (7a,b) in electric interconnection. The first electrode layer is of such configuration as to extend below the lower layer of the top capacitor electrode (9a), with a capacitor insulating film in between. ADVANTAGE - Sufficient capacity for stable data storage even with reduced size of relevant components.

Tantalum capacitor containing fuse capable of discriminating fusion of fuse

Abstract: PURPOSE:To provide a tantalum capacitor containing fuse capable of visually inspecting the fusion state of the fuse simply from outside. CONSTITUTION:For a tantalum capacitor 1 containing a fuse, an irreversible temperature indicating material 9, which discolors at the fusion temperature of the fuse 3, is added to the surface of the tantalum capacitor 1 containing the fuse 3.