Vertical SiGe-base bipolar transistors on CMOS-compatible SOI substrate

We present a comprehensive study of the DC, RF and circuit performance of vertical SiGe-base npn bipolar transistors on 120nm SOI. It includes the sensitivity of device performance to collector doping N/sub C/, layout, and SOI substrate bias. At large positive substrate bias, measured peak f/sub T/, f/sub MAX/ and ECL ring oscillator speed for nominal 180nm devices are 60GHz, 57GHz and 20psec for N/sub C/=1.5/spl times/10/sup 17//cm/sup 3/ respectively, and 71GHz, 54GHz and 18psec for N/sub C/=4.8/spl times/10/sup 17//cm/sup 3/ respectively. Projected f/sub T/ for a scaled 100nm device on 55nm SOI approaches 200GHz.