A 200-mW GaAs 1 K SRAM with 2-ns cycle time

A very high-speed and low-power 1024×1 SRAM has been designed and fabricated using a normally-off recessed-gate FET technology. Minimum gate length is 0.7 μm. A minimum access time of 1.4 ns has been obtained with a power dissipation of 210 mW. The memory cell area is 1197 μm/SUP 2/ and the chip size is 1.91×2.21 mm/SUP 2/. The output voltage swing across a 50-Ω load is 700 mV. The maximum simulated yield for 1 K SRAMs is discussed theoretically. A mean standard deviation in threshold voltage less than 15 mV is required to obtain 100% design yield. The SRAM has been shown to be fully operational using the march and checkerboard tests and exhibits read and write cycle times of 2 ns.