Super self-aligned process technology (SST) and its applications

SST-1B technology, an advanced version of SST-1A, and its applications are described. The main feature is utilization of the selectively ion-implanted collector process to improve shallow base-collector profiles to reduce base width and intrinsic base resistance, and to suppress the base pushout effect. A cutoff frequency of 25.7 GHz and the basic gate delays of 20.5 ps for NTL and 34.1 ps for ECL have been obtained. Using this technology, a number of very high-speed ICs-a 18-GHz 1/8 divider, a 2-Gbsps 6-bit AD converter, and 43-ps/5.2-GHz macrocell array LSIs-have been developed. Concerning future performance, a cutoff frequency of more than 50 GHz for a scaled-down transistor is expected.<
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