Abstract: An MOS/LSI type dynamic RAM with single 5 V supply and grounded substrate employs a guard ring surrounding the cell array to prevent pattern sensitivity in testing. The guard ring is an N+ region biased at Vdd over a deep P+ region in a P-substrate, producing a built-in electric field which attracts diffusing minority carriers into a collecting junction. A standard process for making double-level poly memory devices is modified by adding a P+ implant and deep drive-in prior to field oxidation.

Abstract: A semiconductor dynamic read/write memory device having an array of rows and columns of one-transistor cells employs a single-ended sense amplifier connected to a whole column line, rather than a differential sense amplifier having two inputs connected to column line halves. The single-ended sense amplifier includes an input circuit responsive to a selected threshold voltage, and the output of the amplifier is coupled back to the column line. A dummy cell circuit applies a fixed charge to the column line, so the threshold is exceeded if the selected memory cell stores a 1, but not if a zero is stored.

Abstract: A MOS read only memory, or ROM, is formed by a process compatible with standard P-channel or N-channel metal or silicon gate manufacturing methods. The ROM is programmed either after the protective nitride layer has been applied and patterned, usually the last step in the slice processing method before electrical testing of the devices, or after the electrical testing of the devices. All potential MOS transistors in the ROM array are initially at a logic "0" or a logic "1". An electron beam slice printing machine is used to program the selected transistors in the ROM array to change their logic state by exposing the gates of the selected transistors to an electron beam. The gates to be exposed are predetermined by a coding on a magnetic tape which corresponds to the desired ROM code. No electron beam mask is necessary since the beam only exposes in selected areas.

Abstract: Metal contacts and interconnections for semiconductor integrated circuits are formed by a process using direct-reacted silicide to increase step or sidewall coverage. First a thin layer of titanium or other refractory metal is deposited, extending into a contact hole, then polysilicon is deposited and a preferential etch removes all of the polysilicon except on the vertical sides of steps or apertures. A second thin layer of titanium is deposited, then a heat treatment forms silicide to create conductive sidewalls or a plug. Metal contacts then engage the direct-reacted silicide rather than relying upon step coverage.

Abstract: An MOS/LSI type dynamic RAM with single 5 V supply and grounded substrate employs a guard ring surrounding the cell array to prevent pattern sensitivity in testing. The guard ring is an N+ region biased at Vdd over a deep P+ region in a P-substrate, producing a built-in electric field which attracts diffusing minority carriers into a collecting junction. A standard process for making double-level poly memory devices is modified by adding a P+ implant and deep drive-in prior to field oxidation.

Abstract: A dynamic MOS read/write memory has a substrate bias generator circuit which includes, in this example, four separate pump circuits. A first of these operates only during power-up to quickly produce the desired back bias; this pump circuit uses a high frequency oscillator and a low impedence drive, and cuts off to save power as soon as the necessary bias is reached. A second generates a smaller sustaining current, using a lower frequency oscillator and higher impedance drive; this functions to compensate for leakage during idle periods. The third and fourth pump circuits are driven by RAS and CAS, so these occur only when needed, and at a rate dependent upon the actual operating condition of the memory.

Abstract: A system for real-time digital signal processing employs a single-chip microcomputer device having separate on-chip program ROM and data RAM, with separate address and data paths for program and data. An external program address bus allows off-chip program fetch in an expansion mode, with the opcode returned by an external data bus. A bus interchange module allows transfer between the separate internal program and data busses in special circumstances. The internal busses are 16-bit, while the ALU and accumulator are 32-bit. A multiplier circuit produces a single state 16.times.16 multiply function separate from the ALU, with 32-bit output to the ALU. One input to the ALU passes through a 0-to-15 bit shifter with sign extension. The data RAM has an internal shift arrangement useful in processing convolution algorithms. An addressed location in the RAM is read out and also shifted to the next higher location in one instruction cycle.

Abstract: A microcomputer device contains a CPU with an arithmetic/logic unit and data/address registers on a single semiconductor integrated circuit having on-chip macrocode and microcode storage. In the normal single-chip operation mode, a macrocode word is fethched from on-chip ROM and stored in an instruction register in the CPU, then a sequence of microcode words is fetched from the microcode store based on this macrocode word. In another mode, such as used for self-test employing a check-code, the device loads macrocode from external into on-chip RAM then executes from RAM to perform the desired routine, switching modes of operation.

Abstract: A system for real-time digital signal processing employs a single-chip microcomputer device having separate on-chip program ROM and data RAM, with separate address and data paths for program and data. An external program address bus allows off-chip program fetch in an expansion mode, with the opcode returned by an external data bus. A bus interchange module allows transfer between the separate internal program and data busses in special circumstances. The internal busses are 16-bit, while the ALU and accumulator are 32-bit. A multiplier circuit produces a single state 16.times.16 multiply function separate from the ALU, with 32-bit output to the ALU. One input to the ALU passes through a 0-to-15 bit shifter with sign extension.

Abstract: A dynamic read/write memory device using one-transistor N-channel silicon gate type cells is made by a double-level polysilicon process in which the field oxide is of reduced thickness for the cell array, and of conventional thickness for peripheral circuits. This reduces moat encroachment in the critical cell portion, yet does not force performance compromises in the critical speed paths.

Abstract: A microprocessor device with an on-chip integrated auto-loaded timer is used in an adapter for a communications loop of the token-passing local area network type. The network has a number of stations coupled to a closed one-way signal path, and each station has a host processor with a host CPU and memory. The microprocessor device with integrated auto-loaded timer is part of an adapter coupled to the host processor. A message frame to be transmitted is copied into a local read/write memory in the adapter by way of the host system bus and a local bus, under initiation by the host CPU. A transmit-and-receive controller is coupled to the local bus to directly access the local read/write memory; when this station has access to the loop (i.e., receives a free token) the transmit-and-receive controller copies the message frame from the local read/write memory to the outgoing signal path, converting from parallel to serial.

Abstract: A method of making MOS integrated circuits employs high-pressure oxidation of the surface of a silicon slice to create thermal field oxide for device isolation. The implant used prior to this oxidation to provide the channel-stop regions beneath the field oxide may be at a lower dosage, and yet the field-transistor threshold voltage is maintained at a high level. Thus, encroachment of the channel stop impurity into the transistor channel is minimized, and higher density devices are permitted.

Abstract: A transistor for VLSI devices employs a phosphorus implant and lateral diffusion performed after the sidewall oxide etch to thereby reduce the impurity concentration and provide a graded junction for the reach-through implanted region between heavily-doped N+ source/drain regions and the channel, beneath the oxide sidewall spacer.

Abstract: A semiconductor dynamic memory device has an array of one-transistor cells, with row and column decode to produce a 4-bit wide input or output. Single-bit data-in and data-out terminals for the device may be coupled to the 4-bit array input/output in a sequential mode. The row and column addresses are latched when RAS and CAS drop, and this includes the address of the starting bit within the 4-bit sequence. The other three bits follow as CAS is cycled. This starting address is used to set a bit in a 4-bit ring counter, which is then used to cycle through the sequence.

Abstract: A programmable device is provided by a thin-oxide avalanche fuse element which is programmed at a voltage below the oxide breakdown level. This device may be used to fix the addresses of faulty rows or columns in a memory having redundant or substitute cells. Upon breakdown, the thin oxide is perforated by small holes which fill with silicon to create short circuit. The source or emitter of the transistor device may be separated from the drain and gate by thick filled oxide.

Abstract: A dynamic read/write memory or the like is made by a twin-well CMOS process that employs field-plate isolation rather than thick field oxide, with no separate channel stop implant. The field plate is grounded over P well areas, and connected to the positive supply over the N wells. One-transistor memory cells are of metal-gate construction with N+ drain regions buried beneath oxide, and other transistors are constructed with silicided, implanted, source/drain regions, self-aligned to the metal gates, employing sidewall oxide spacers to provide lightly-doped drains.

Abstract: A video display system employs a memory arrangement for the video data which is sequentially accessed for serial read-out of the bit-mapped video information at a high clock rate, and also randomly accessed in parallel by a microcomputer for generating and updating the information to be displayed. Parallel access to the memory by the microcomputer can occur while the serial video data is being clocked out, so microcomputer I/O and video output conflict only a very minimum amount. Dynamic MOS RAMs with a serial register added provide this dual port memory.

Abstract: A CMOS bistable circuit is employed as an address buffer or latch for a semiconductor memory or the like. The circuit includes a pair of differential gated inputs, one from an address terminal, and the other from a reference voltage. The same clock used to gate the inputs also preconditions the circuit to be in a balanced status, and holds off conduction of any transistor in the circuit. In this manner, a circuit of high speed, low power, and minimum complexity is provided.

Abstract: An electrically erasable, programmable memory cell array of the floating gate type is made by a process which allows an erase window for the first level polysilicon floating gate to be positioned beneath a third level poly erase line, while maintaining a small cell size. The erase window is not beneath the second level poly control gate, so degrading of the stored charge by the read mechanism is minimized.

Abstract: A semiconductor dynamic read/write memory device using one-transistor storage cells and balanced bit lines employs a differential sense amplifier having dual sets of transistors for both the N-channel and P-channel transistor pairs in a CMOS flip-flop circuit. One set of P and N channel transistors is cross-coupled in the conventional manner, and the other set is cross-coupled by way of series transistors which are shut off for write operations, bypassing static loads for write.