Advanced process technology for a 40-GHz fT self-aligned bipolar LSI

Abstract

This paper describes an optimum rapid thermal processing technology which is suitable for a 40 GHz cut-off frequency (fT) bipolar LSI. Three new techniques have been developed for this purpose. One is in-situ phosphorus doped polysilicon (IDP) emitter technique for reducing thermal budget. Rapid thermal annealing (RTA) technique is used to reduce the emitter-base junction leakage current and to form a shallow junction. And low damage dry etching technique reduces thermal budget for recovery of silicon surface. Using this new technology, high fT of 40 GHz and low E-B junction leakage current have been achieved.