Abstract: The invention provides fast generation of flag signals for devices such as a first-in first-out buffers by looking ahead and predetermining flag signals for future possible states of the device. Predetermining flag signals does not delay flag output because the required calculations are completed before the flag signal is needed. The flag signal can be changed when needed as quickly as a multiplexer can switch from an old flag signal to a predetermined flag signal. The switching time of a multiplexer is shorter than the comparator delays in prior art flag generators.

Abstract: A synchronous SRAM (or DRAM or other logic) chip with input registers (or latches) associated with the chip memory cell array input lines, where there is logic associated with the registers, locates the logic gates upstream of the registers and connected to the D input of each register. Hence the logic gates not only provide the needed logic function, but also provide the necessary delay to meet the specified hold time delay in synchronous circuits. This reduces the logic function after the input registers and hence improves the clock-to-output access time of the chip.

Abstract: An MOS transistor for use in an integrated circuit is fabricated with a self-aligning contact and interconnect structure which allows for higher packing density. Self-aligning source and drain contacts overlap the gate but are prevented from a short circuiting to the gate by oxide insulation between the source/drain contacts and the gate, and a layer of silicon nitride above the gate. Contacts to the gate are made on top of the gate over the active region of the transistor because the source and drain regions are protected by a hardened layer of photoresist during etching of insulation to expose the gate contact. Source, drain and gate contacts are protected by a layer of titanium silicide so that interconnects are not required to completely cover these areas. Low resistance interconnects are formed of doped polysilicon covered by titanium silicide encapsulated by a thin film of titanium nitride.

Abstract: The invention provides fast generation of flag signals for devices such as a first-in first-out buffers by looking ahead and predetermining flag signals for future possible states of the device. Predetermining flag signals does not delay flag output because the required calculations are completed before the flag signal is needed. The flag signal can be changed when needed as quickly as a multiplexer can switch from an old flag signal to a predetermined flag signal. The switching time of a multiplexer is shorter than the comparator delays in prior art flag generators.

Abstract: A compact cell design for a static random access memory cell is achieved. The cell has two transistors with gates substantially parallel to each other. One interconnect connects the gate of one transistor to an electrode of the other transistor. Another interconnect connects the gate of the other transistor to an electrode of the first transistor. The two gates and the two interconnects form substantially a rectangle. A power supply circiut line is disposed outside the rectangle. This line and the two interconnects are formed from one conductive layer.