Abstract: Disclosed are memory cells of a vertical-type read only memory (ROM) having a plurality of MISFETs connected in series. The MISFETs include gate electrodes formed with multiple conductive layers, in which some of the MISFETs are set to the depletion type and at least some of the remaining MISFETs are set to the enhancement type, so as to write information in the memory cells. The information write operation is conducted through at least two steps. Namely, in the first information write step, gate electrodes are used as a mask to implant an impurity; and in the second step, an impurity is implanted through the gate electrodes into the surface of the semiconductor substrate. These steps enable a semiconductor memory device, such as a vertical-type mask ROM having memory cells with a reduced series resistance and being suitable for a high degree of integration, to be produced.

Abstract: A symmetrical blocking high breakdown voltage semiconductor device in which the lower junction termination is brought to the upper surface is fabricated by diffusing first and second regions of a first conductivity type into an upper surface of an epitaxial layer of a second conductivity type disposed on a substrate, and forming a groove having sloped sidewalls in the upper surface such that the groove extends through the second diffused region, the epitaxial layer and into the substrate. A thin layer of impurities of the first conductivity type is implanted into the sidewalls, and the impurities are electrically activated to form a low resistivity path that connects the substrate to the second diffused region. Subsequently, the semiconductor device may be separated from the wafer by cutting the wafer at the groove. The manufacturing process enables substantially complete fabrication of a plurality of devices while still in wafer form, thereby avoiding the inconvenience of processing individual dice.

Abstract: A method of manufacturing a semiconductor device in which a conductive layer (6) provided on a surface (4) of a semiconductor body (1) is formed with at least one opening (10). The semiconductor device may be an insulated gate field effect transistor (IGFET) in which case the opening (10) defines a hollow gate structure for the IGFET. Insulating material (16') is grown on the surface (4) to cover the conductive layer.

Abstract: A method for manufacturing double-diffused metal-oxide-semiconductor field effect transistor (DMOSFET) device is to form an insulating layer having an opening in top surface on a semiconductor wafer, channel regions and well regions and source regions through two stage diffusions of impurity materials respectively of a different conductivity type from and the same conductivity type as the wafer and carried out through the opening, and further gate, source and drain electrodes are formed after masks provided on a surface area where the drain regions and the source electrode regions that are to be connected to the well regions and source regions and a further ion-implantation of an impurity material of the same conductivity type as the wafer into the channel regions, with the threshold voltage controlled to achieve a depletion type.

Abstract: An optical memory comprising a doping modulated multilayer made of amorphous semiconductor, and at least two electrodes, one of the electrodes being transparent and the multilayer being sandwiched between two electrodes. Data is written by increasing the electrical conductance of the amorphous semiconductor by irradiating it is light. Data is erased by the application of a bias voltage to the electrodes and also by irradiating the amorphous semiconductor with light having photon energy of approximately half or less of the optical energy band gap of the amorphous semiconductor. The memory effect can be maintained for a week or longer, and the memory can be erased without heating the memory device, whereby the lifetime of the device is lengthened.

Abstract: A process of forming a power MOSFET that needs only a single masking step. A layer of gate oxide and a layer of polysilicon are formed in turn over one surface of a silicon wafer and the polysilicon layer is partially oxidized to form a covering polyoxide layer. The polyoxide and polysilicon layers are apertured to define the source regions of the cells of the transistor. Donor and acceptor ions are introduced by way of the openings into the wafer to form localized source regions each enclosed by a separate region of the opposite conductivity type, surface portions of which underlie the polysilicon layer and serve as the channels of individual cells of the transistor. Dielectric tabs are provided along the sidewalls of the openings which are then filled by an overlying conductive layer that serves as the source electrode of the transistor for each of the cells. The polysilicon layer serves as a common gate electrode for each of the cells.

Abstract: A dopant-opaque layer of polysilicon is deposited on gate oxide on the upper substrate surface to serve as a pattern definer during fabrication of the device. It provides control over successive P and N doping steps used to create the necessary operative junctions within a silicon substrate and the conductive structures formed atop the substrate. A trench is formed in the upper silicon surface and a source conductive layer is deposited to electrically contact the source region as a gate conductive layer is deposited atop the gate oxide layer. The trench sidewall is profile tailored using a novel O.sub.2 --SF.sub.6 plasma etch technique. An oxide sidewall spacer is formed on the sides of the pattern definer and gate oxide structures, before depositing the conductive material. A planarizing layer is applied and used as a mask for selectively removing any conductive material deposited atop the oxide spacer.

Abstract: A method of manufacturing a semiconductor device in which a lateral insulated gate field effect transistor (IGFET) (1) is provided by defining an insulated gate structure (12) on a given surface (3a) of a semiconductor body (3) by providing an insulating layer on the given surface (3a) having a relatively thin region on a first area of the given surface adjoining a relatively thin region (14a) on a second area (31b) of the given surface and providing a conductive layer (15,16) on the insulating layer to define an insulated gate over the first area of the given surface with the conductive layer extending up onto the relatively thick region of the insulating layer.

Abstract: A method of manufacturing a semiconductor device in which a base of a second conductivity type is provided in a semiconductor substrate of a first conductivity type, which operates as a collector. An emitter of the first conductivity type is provided in the base, a pn junction between the collector and the base is exposed on the surface of the semiconductor substrate, and the emitter is provided with stabilizing resistors. The method comprises the steps of providing a silicon oxide film over the entire surface of the semiconductor device, and a polysilicon film over both the emitter and a first portion of the pn junction exposed on the surface of the semiconductor substrate, and impurities are diffused into only a second portion of the polysilicon film located over the emitter to reduce the resistance of the second portion of the polysilicon film.

Abstract: Interconnections interconnecting terminals to be connected by routings are dissolved into two-terminal interconnections and it is determined to which kind of terminals the terminals of each two-terminal interconnection belong, among connected diffusion layer, separated diffusion layer and gate. The interconnections are classified into groups by the combination of the kind of two terminals for each interconnection. The respective groups of interconnections are routed in the channel on the field effect transistor row according to a predetermined order of groups.

Abstract: Double injection field effect transistors, which may be horizontally or vertically arranged, each include a body of semiconductor material extending between two current-carrying electrodes and forming a current path therebetween. The semiconductor body of each may be substantially intrinsic or lightly doped. One or more control electrodes or gates located adjacent to each current path project a variable electric field over the ambipolar path, which modulates current by controlling the amount of charge carriers of both polarities injected into the semiconductor body. In most of the single gate embodiments, the electrodes extend across a portion, preferably a major portion such as 75% or 90%, or the length of the current path, but not the entire length of the current path. The embodiments having a plurality of gates typically have two insulated gates, one extending from the anode electrode and the other extending from the cathode electrode. The gates in a single device may overlap.

Abstract: The present invention is a method for fabricating bipolar-MOS devices having n-MOSs, p-MOSs and bipolar transistors, each fabricated in a respective silicon single crystal layer grown in openings formed in a field oxide layer covering a silicon substrate. Over the field oxide layer, having openings where the active devices should be fabricated, is applied an epitaxial growth of silicon. By this operation, single crystal layers are formed in the openings, and a polysilicon layer is formed on the field oxide layer. The polysilicon layer is patterned to form the source and drain contact electrodes of the FETs and the base and collector contact electrodes of the bipolar transistors simultaneously. To the active areas, contact electrodes for the p-MOS, and base contact electrodes of the npn bipolar transistors are simultaneously implanted with p type impurities by ion implantation.

Abstract: A programmable low impedance interconnect diode element is disclosed having a lower electrode formed of a semiconductor material of a first conductivity type covered by an insulating dielectric layer which may be in a preferred embodiment comprised of an initial layer of silicon dioxide, a second layer of silicon nitride and a third layer of silicon dioxide, covered by a layer of semiconductor material of a second conductivity type.A programmable read only memory array and a programmable logic array comprising a plurality of the above-described cells are also disclosed.

Abstract: A process for forming an asymmetrically structured pair of CMOS field effect transistors having feature refinements matched to the individual idiosyncrasies of the p-channel and n-channel transistors. Complementary transistors are formed using a single photolithographic mask and a fabrication sequence which begins with the p-channel transistor source/drain formation. Thereafter, the p-channel transistor source/drain regions are metalized, the n-channel transistor lightly doped drain regions are formed, and the sidewall dielectric spaced n-channel transistor source/drain regions are formed using the p-channel metalization as a mask. The p-channel transistor source/drain metalization suppresses the effects of the relatively greater p-type source/drain resistivity, while the LDD structure of the n-channel transistor reduces performance degradation attributable to hot electron trapping.

Abstract: A solid state relay includes a MOS FET receiving a photovoltaic output generated across a photovoltaic diode array responsive to a light signal from a light-emitting element, and a normally ON driving transistor connected to the MOS FET, the driving transistor being connected at control electrode to a connection point between the photovoltaic diode array and an impedance element to be biased by a voltage generated across the impedence element during generation of the photovoltaic output across the photovoltaic diode array to have a high impedance state, whereby the relay can be prevented from providing at output terminals any intermediate state between ON and OFF states even when an input current to the relay is in lower range, and a high speed relay operation is realized.

Abstract: A method of making a variable-capacitance diode device including semiconductor layer a first conductivity type in which the impurity concentration decreases with increasing depth from surface of a PN junction. The semiconductor layer of the first conductivity type is formed by diffusing an impurity element of the first conductivity type in a semiconductor substrate with a high degree of concentration. Thereafter, a semiconductor layer of a second conductivity type is formed which has such an impurity concentration profile that the concentration of impurity element of the second conductivity type is lower than the impurity concentration of said semiconductor layer of the first conductivity type formed in said semiconductor substrate and at a predetermined depth, the concentration of the second conductivity type impurity element is substantially equal or close to the concentration of the first conductivity type impurity element.

Abstract: A semiconductor device having a conductive recombination layer. The conductive recombination layer, comprised of doped polycrystalline material, doped polycrystalline material and tungsten silicide, or tungsten silicide, is disposed between two separate semiconductor substrates which are bonded together using a polished surface on the conductive recombination layer as one of the bonding interfaces. The conductive recombination layer recombines minority carriers and thereby increases the switching speed of the device.

Abstract: Metal contacts and interconnections for integrated circuits utilize copper as the primary conductor, with the copper being totally encased in refractory metal layers on both top and bottom surfaces and also sidewalls. The contact hole in silicon oxide may be filled with a plug of refractory metal before the copper is deposited, or the first refractory metal layer may be conformally deposited to coat the sidewalls of the hole.

Abstract: Disclosed is a process for forming self-aligned low resistance ohmic contact to a P doped region (e.g., base of an NPN device) in conjunction with forming similar contact to a (highly) N doped region (e.g., emitter of NPN). After forming a P doped region in an N type monocrystalline silicon body and masking it with an insulator (e.g. dual oxide-nitride) layer, the highly doped N region (hereafter, N+ region) is formed in a portion of the P doped region by selectively opening the insulator layer and introducing N dopant therethrough. This opening also serves as contact opening for the N+ region. contact opening for the P region is formed by selectively etching the insulator layer. The structure is subjected to a low temperature steam oxidation to from an oxide layers in the P contact and N+ contact regions, the oxide in the N+ contact being about 3-5 times thicker than that in the P contact region due to the significantly higher oxidation rate of the N+ region relative to the P doped region.