Abstract:
A non-blocking load buffer is provided for use in a high-speed microprocessor and memory system. The non-blocking load buffer interfaces a high-speed processor/cache bus, which connects a processor and a cache to the non-blocking load buffer, with a lower speed peripheral bus, which connects to peripheral devices. The non-blocking load buffer allows data to be retrieved from relatively low bandwidth peripheral devices directly from programmed I/O of the processor at the maximum rate of the peripherals so that the data may be processed and stored without unnecessarily idling the processor. I/O requests from several processors within a multiprocessor may simultaneously be buffered so that a plurality of non-blocking loads may be processed during the latency period of the device. As a result, a continuous maximum throughput from multiple I/O devices by the programmed I/O of the processor is achieved and the time required for completing tasks and processing data may be reduced. Also, a multiple priority non-blocking load buffer is provided for serving a multiprocessor running real-time processes of varying deadlines by prioritization-based scheduling of memory and peripheral accesses.
Abstract:
Methods for improving adhesion between various materials utilized in the fabrication of integrated circuits. A first method relates to improving adhesion between a silicon nitride layer and a silicon dioxide layer. The method includes treating a surface of the silicon dioxide layer with a nitrogen plasma in a reactive ion etching process prior to depositing the silicon nitride film on the surface of the silicon dioxide layer. A second method relates to improving adhesion between a silicon nitride layer and a polyimide layer. The method includes the step of treating a surface of the silicon nitride layer with a oxygen/argon plasma in a reactive ion etching process prior to depositing the polyimide layer film on the surface of the silicon nitride layer. A third method relates to improving adhesion between a photoresist layer and a metal. The method includes the step of treating a surface of the photoresist layer with a oxygen/argon plasma in a reactive ion etching process prior to depositing the metal on the surface of the photoresist layer.
Abstract:
The present invention encompasses techniques for reducing digital noise in integrated circuits and circuit assemblies, particularly dense mixed-signal integrated circuits, based upon shaping the noise from the digital circuit and concentrating it in a single, or a small number, of parts of the frequency spectrum. Generally, the presence of noise in the analog circuit is less important at certain frequencies, and therefore the spectral peak or peaks from the digital circuit can be carefully placed to result in little or no interference. As an example, a radio receiver might be designed such that the peaks of the digital noise lie between received channels, outside the band edges of each.
Abstract:
A circuit for isolating an interconnect line from unwanted input signal voltage levels is described. One implementation of the circuit includes a transmission gate coupled in series between an input signal and an interconnect line having its gate coupled to the output of an inverter and the input of the inverter coupled to the input signal. The inverter senses the input signal and when it sense voltages that are either too high or low, the isolation circuit decouples the input signal from the interconnect line such that the input signal can transition independently with respect to the voltage levels on the interconnect line.
Abstract:
A compact Finite Impulse Response (FIR) filter using one or both of a compact address sequencer and a compact multiplier/accumulator. The address sequencer exploits certain symmetry properties existing between different phases of a polyphase FIR filter in order to reduce coefficient storage and simplify address sequencing. The multiplier/accumulator is capable of performing two multiply/accumulate operations per clock cycle, avoiding in certain instances the need to add a second multiplier/accumulator. The area required to realize a FIR filter for performing real-time filter is therefore reduced.
Abstract:
A bipolar transistor having an emitter, a base, and a collector includes an intrinsic base region having narrow side areas and a wider central area. The side areas are located adjacent to the extrinsic base region, while the central area is disposed underneath the emitter. The lateral doping profile of the base is tailored so that the doping concentrations in the extrinsic region and the central area are relatively high compared to the doping concentration of the narrow side areas of the intrinsic base. The combination of the narrow side areas and the lateral base doping profile constrains the depletion region within the base thereby lowering punch-through voltage of the transistor without loss of beta.
Abstract:
A microscopic laminar-flow heat exchanger, well-suited for cooling a heat generating device such as a semiconductor integrated circuit, includes a plurality of thin plates, laminated together to form a block. Each plate has a microscopic recessed portion etched into one face of the plate and a pair of holes cut through the plate such that when the block is formed, the holes align to form a pair of coolant distribution manifolds. The manifolds are connected via the plurality of microscopic channels formed from the recessed portions during the lamination process. Coolant flow through these channels effectuates heat removal.
Abstract:
A process for faricating polysilicon resistors and polysilicon interconnects coupled to MOS field-effect devices in a silicon substrate includes the steps of depositing and etching a first polysilicon layer to form the gates of the MOS devices; then depositing a second layer of polysilicon between the gates. The second polysilicon layer is then etched so that its upper surface is substantially coplanar with the gates. Contact openings are then defined to the source, drain and gate members of the devices through an insulative layer formed over the first and second polysilicon layers. Next, a metal layer is deposited to fill the openings and is patterned to define electrical contacts to the devices. The patterning step also defines the interconnect lines in the metal layer. A third polysilicon layer is then deposited and patterned to define the polysilicon resistors and interconnects.
Abstract:
A processor and method for performing outer product and outer product accumulation operations on vector operands requiring large numbers of multiplies and accumulations are disclosed.
Abstract:
A general purpose processor with four copies of an access unit, with an access instruction fetch queue A-queue (101-104). Each A-queue (101-104) is coupled to an access register file AR (105-108) which is coupled to two access functional units A (109-116). In a typical embodiment, each thread of the processor may have on the order of sixty-four general purpose registers. The access unit functions independently by four simultaneous threads of execution, and each compute control flow by performing arithmetic and branch instructions and access memory by performing load and store instructions. These access units also provide wide specifiers for wide operand instructions. These eight access functional units A (109-116) produce results for access register files (105-108) and memory addresses to a shared memory system (117-120).