Abstract: A process is provided for fabricating self-aligned contacts to the surface of an integrated circuit. The process includes the steps of depositing a layer of silicon dioxide 12 on the surface of a semiconductor structure 10; depositing a layer of polyimide 15 on the surface of the silicon dioxide 12; defining openings 23 in the polyimide material 15 and the silicon dioxide 12 to thereby expose regions of the semiconductor structure 10; and depositing metal 22 across the underlying surface and in the openings 23. In the preferred embodiment metal 22 is substantially the same thickness as silicon dioxide 12, and polyimide material 15 is masked using sequentially deposited layers of silicon dioxide 18 and photoresist 21.

Abstract: A lateral bipolar transistor having a base width of 0.

Abstract: A method for encoding binary data into an electrically erasable memory. The memory includes a matrix of memory cells formed as a plurality of rows (X write lines/X sense lines/source lines) and columns (Y sense lines) with each cell including a floating gate field effect PMOS transistor and an NPN bipolar transistor. The method includes applying an erase voltage, e.g. +20 volts, to each of the Y sense lines while maintaining each of the X sense lines at this erase voltage and each of the X write lines at ground and applying the erase voltage to each of the source lines such that each of the PMOS transistors assumes a relatively negative threshold state. The method includes applying a write voltage e.g., +20 volts, to selected X write lines while maintaining unselected X write and selected Y sense lines at ground and unselected Y sense lines at an inhibit voltage e.g., +10 volts, which is less than the write voltage, and maintaining each of the X sense lines at an intermediate voltage e.g.

Abstract: A self-refreshing non-volatile memory cell having two cross-coupled transistors includes a first floating gate formed between the gate and the channel of said first transistor, said first floating gate overlying by means of a tunnel oxide a portion of the drain of said second transistor and a second floating gate formed between the gate and channel of said second transistor, a portion of said second floating gate overlying by tunnel oxide a portion of the drain of the first transistor. Disturbances in the supply voltage and the gate voltage of the device normally enhance rather than degrade the state of data stored in the cell, thereby providing an extremely long storage time for the cell. The cell is capable of operating simultaneously in a volatile and a non-volatile state.

Abstract: A semiconductor structure is fabricated using a process involving all ion implantation and using only five masks prior to metallization. A buried contact mask is used to form a buried contact layer (114), an isolation mask is used to form grooves (130a, 130b) in an epitaxial layer of silicon (113), a self-aligned transistor mask is used to form a mask (134a to 134e) to define the areas in which emitters (138a, 140b, 140c) bases (113, 139) and contact regions (140a) are to be formed, a base exclusion mask (135a,b) is provided to exclude certain impurities from being implanted into a region to be formed of one conductivity type, and a second exclusion mask (137a, 137b) is provided to exclude impurities to be implanted in a region of opposite conductivity type from the prohibited regions of the structure.

Abstract: In a method for welding a lead wire or bonding wire from a microcircuit chip mounted on a lead frame to a lead frame finger, the lead frame finger is preheated prior to any substantial electrical or thermal coupling between the lead frame finger and chip. Intense but controlled energy is applied to the lead frame finger at levels which might otherwise damage the IC chip. In one embodiment the lead frame finger is preheated to a temperature below the melting point of the metal comprising the lead frame. Enhanced bonding is thereafter effected by thermocompression bonding etc. In another embodiment the preheating step comprises melting a portion of the surface of the lead frame finger, forming a molten pool or puddle in the surface. Bonding of the lead wire is effected by immersing a section of the wire in the molten pool or puddle. In order to preheat the lead frame finger a controlled pulse train is delivered for arc discharge at the bonding location.

Abstract: In a digital tester for evaluating electronic components, a local memory unit for each data channel in the tester is loaded with test vector information only in the locations of the memory relating to transitions that take place in the operation of the data channel. In addition, a transition bit is stored in each memory location to signify whether the vector information in that location represents valid transition data. The transition bit is used to control the reading of information from the memory into a register that controls the flow of information in the data channel, so that only the valid transition vectors are fed into data channel control circuitry. This procedure substantially reduces the amount of data that must be loaded into the memory, and hence reduces the total time necessary to thoroughly test a circuit.

Abstract: In a semiconductor device, laser energy is used to selectively heat various SiO.sub.2 and/or GeO.sub.2 based materials to elevated temperatures while maintaining the active device region and electrical interconnects at relatively low temperatures, to for example, induce densification and/or flow of the SiO.sub.2 and/or GeO.sub.2 based material to round off sharp edges and stops, without damaging or affecting the active region and electrical interconnects.

Abstract: A process is described for removing polyimide regions adhered to the surface of a semiconductor structure 10 which includes the steps of heating the structure 10 and the polyimide regions 12 to between 450.degree. and 490.degree. C., immersing the structure in a solution of one of methylene chloride and ethylene diamine/hydrazine, and ultrasonerating the solution and the semiconductor structure.

Abstract: A process and structure are disclosed which are suitable for forming large arrays of Schottky diodes at desired locations between mutually perpendicular strips of aluminum and strips of metal-silicide. The invention is particularly useful in creating read-only memories and programmable logic arrays, and allows fabrication of Schottky diodes more compactly than previous structures.

Abstract: A self-refreshing non-volatile memory cell having two cross-coupled transistors includes a first floating gate formed between the gate and the channel of said first transistor, said first floating gate overlying by means of a tunnel oxide a portion of the drain of said second transistor and a second floating gate formed between the gate and channel of said second transistor, a portion of said second floating gate overlying by tunnel oxide a portion of the drain of the first transistor. Disturbances in the supply voltage and the gate voltage of the device normally enhance rather than degrade the state of data stored in the cell, thereby providing an extremely long storage time for the cell. The cell is capable of operating simultaneously in a volatile and a non-volatile state.

Abstract: Defects in dielectric layers exhibiting low dielectric strength on silicon substrates (11) are deliberately damaged during manufacture to allow their repair by the formation of dielectric plugs (13B). The defects are damaged by the application of an electric field, and are repaired by the selective oxidation or nitridation of the silicon substrate underlying the damaged areas of dielectrics.

Abstract: A novel process is disclosed for the selective etching of a protective layer over a substrate according to a predetermined pattern, which does not involve the use of chemical vapor deposition or vacuum techniques. The process incorporates the techniques of electroless metal deposition after first applying a mask which is positive with respect to the predetermined pattern. In alternative embodiments, the application to the masked protective layer of an agent catalytic to the reception of electroless metal deposition is followed by either immersion in an electroless plating bath and subsequent mask removal, or by mask removal and subsequent immersion in the electroless plating bath. In either embodiment, the protective layer is effectively masked and patterned for plasma etching. The process is useful in forming openings in the protective layer to permit selective doping of the underlying substrate.

Abstract: An integrated circuit structure and process for fabricating it are described which allow fabrication of a very compact high-speed logic gate. The structure utilizes a bipolar transistor formed in an epitaxial silicon pocket surrounded by silicon dioxide. A pair of Schottky diodes and a resistor are formed outside the epitaxial pocket on the silicon dioxide and connected to the pocket by doped polycrystalline silicon.

Abstract: A method and apparatus is described for dynamically testing the overall performance characteristics of digital-to-analog converts and analog-to digital converters which involve excitation of the converters by an orthogonal function signal. Specifically the method comprises dynamically exercising a converter with an analog or digital signal pattern characterized by the sum of a set of mutually orthogonal functions, the sum having substantially uniform amplitude distribution among allowable states (maximum entropy), and simultaneously examining the output response of the converter for a plurality of basic performance parameters. The basic performance parameters typically include distortion, linearity and optimum gain. The simultaneous examination involves sorting out expected responses to simultaneously applied orthogonal signals. The method yields a relatively complete statistical description of the performance characteristics. The preferred excitation is based on the Walsh functions.

Abstract: The method of the invention provides a thin film deposit of a binary glass for use in integrated circuits which binary glass has a softening or flow point far below temperatures at which glasses normally used in connection with integrated circuits flow. After the binary glass has been deposited (on a semiconductor substrate), it is heated and reflowed. Preferably the glass comprises a mixture of germanium dioxide and silicon dioxide wherein the germanium dioxide is no greater than approximately 50 mole percent of the mixture. Phosphorus is added to the glass film for passivation of the underlying devices.

Abstract: A method for scanning the top surface of a semiconductor wafer prevents damage to the wafer (11) by ensuring that the laser beam (13) does not cross over the edge (11a) of the wafer during the scanning process nor approach within one (1) to two (2) millimeters to the edge of the wafer.

Abstract: A microprocessor comprising: an address data path; an arithmetic logic unit data path, said data paths being capable of simultaneous operation; an information bus; a shared bus register; a shared input multiplexing apparatus for selectively transferring address and data information from said information bus and data information from said arithmetic logic unit data path to said shared bus register; and a multiplexing apparatus for transferring information from said shared bus register to said arithmetic logic unit data path and to said information bus via said address data path whereby said shared bus register is selectively useable as a memory data register, a memory address register and a temporary or "scratch-pad" register during normal operation of the microprocessor; and further comprising; a programmable logic array containing a sequence of microinstructions and apparatus connected thereto for testing the operability of the microprocessor.

Abstract: A method of removing bulk impurities from a semiconductor wafer is described comprising the steps of lapping the front and back surfaces of the wafer to remove 35 to 40 microns of material therefrom and to make the surfaces parallel, heating the wafer at a predetermined temperature preferably equal to or above the highest temperature to be used in subsequent device fabrication, etching the front and back surfaces of the wafer to remove 35 to 40 microns of material therefrom and thereafter polishing the front surface of the wafer for removing 20 microns of material therefrom. By means of the above process the number of surface defects caused by strain producing centers in the crystal lattice of the wafer is reduced from 500,000 defects per square centimeter to less than 1,000 defects per square centimeter.

Abstract: An address gate for a random access memory includes a pair of emitter-coupled and collector-coupled transistors, and another transistor emitter-coupled to the pair of transistors. Complimentary outputs are read at the coupled emitters of the pair of transistors and the collector of the other transistor respectively, there being an input signal applied to the base of one of the pair of transistors, and a control signal applied to the base of the other of the pair of transistors, which overrides the operation of one of the pair of transistors when the control signal is in its high state.