HIGHLY LATCHUP-IMMUNE 1- mu m CMOS TECHNOLOGY FABRICATED WITH 1 Mev ION IMPLANTATION AND SELF-ALIGNED TiSi//2.

A 1- mu m n-well CMOS technology with high latchup immunity has been designed, realized, and characterized. The main features of this technology are: 1-MeV ion-implanted retrograde n-well buried-contact arsenic-phosphorous double-diffused n** plus /n- junction; self-aligned TiSi//2 on gate and diffusions with nitride spacer; and thin p epi on p** plus substrate. This technology has been demonstrated via the successful fabrication of high-performance 64 K CMOS SRAM chips. It has been observed that the silicide plays an important role in latchup prevention since it reduces the emitter efficiencies of parasitic bipolar devices.