OXIL, A Versatile Bipolar VLSI Technology

A bipolar VLSI technology, for Oxide Isolated Logic (OXIL) circuits has been developed which combines high-frequency conventional down-transistors with inverted up-transistors which are fabricated in a common process on the same chip site. The up-transistor is especially designed to optimize I/sup 2/L circuits for high packing density, speed, and performance. High-pressure-steam oxide isolation and an up-diffused active base are combined to fabricate the up-transistor with f/sub t/ > 500 MHz and Beta = 100, which allows I/sup 2/L delays down to 3 ns at FO = 1 and 7 ns at FO = 6. The down-transistor is an oxide-isolated implanted-base transistor with an As emitter. It exhibits gains of 100-150 at f/sub t/ = 2 GHz and supports subnanosecond CML, high-current buffer circuitry, and linear interfacing.