290 psec I2L circuits with five-fold self-alignment

New, high speed, self-aligned IIL structures with minimum gate delays of 290 psec/gate(fanout=1) and power delay products of 30 fJ/gate at low injector current levels with 3 µm × 3 µm collectors are demonstrated. Maximum toggle frequency in an IIL T-type flip-flop is measured at 2 mW and found to be up to 220 MHz.