GaAs E/D MESFET 1-kbit static RAM fabricated on silicon substrate

A GaAs enhancement/depletion (E/D) MESFET 1-kbit static RAM has been fabricated on a 2-in GaAs-on-Si substrate. This is the most complex GaAs circuit reported to date for GaAs-on-Si material. The GaAs layer is grown on a (100) silicon wafer by MBE. Excellent threshold voltage uniformity has been obtained for enhancement- and depletion-mode MESFET's. The row-address access time of the 1-kbit SRAM is 6-14 ns compared with 4-12 ns for bulk GaAs chips fabricated concurrently using the identical E/D MESFET process. The total power dissipation, of less than 500 mW, is also comparable to the bulk GaAs chips.