A Radiation-Hard CMOS/SOS ALU

A radiation-hard CMOS/SOS technology has been used to fabricate a complex LSI circuit containing over 2200 transistors. The circuit is an eight bit wide arithmetic and logic unit (ALU) slice. This paper describes the results of electrical, temperature, and radiation tests on the ALU circuit. An instruction cycle-time of less than 240 ns was achieved for nominal operation at +11V and 25° C. This time increases to 300 ns at 125° C. After irradiation to 106 rads (Si) under bias, operation was degraded only slightly. The 25° C and 125° C postradiation cycle times were within 320 and 360 ns, respectively. Radiation tolerance from part to part and lot to lot was excellent, thus demonstrating the applicability of radiation hard CMOS/SOS to LSI circuitry.