Total dose radiation hard 0.5 /spl mu/m SOI CMOS transistors and 256 K SRAMs

The first 2 Mrad(SiO/sub 2/) total dose hard 0.5 /spl mu/m CMOS SOI 256 K SRAM fabricated in SIMOX has been demonstrated. The address access time varied from 15 ns at 3.6 V to 19 ns at 3.0 V. The address access time was nearly independent of temperature from -55/spl deg/C to 125/spl deg/C and independent of radiation to 2/spl times/10/sup 6/ rad(SiO/sub 2/) for a given Vdd. The standby current was 0.5 mA at 2/spl times/10/sup 6/ rad(SiO/sub 2/) which was much better than the specified 1.5 mA.