Christoph Schwan

RF-pFET in fully depleted SOI demonstrates 420 GHz F T

We report an experimental pFET with 420GHz fT, which to the best of our knowledge is the highest value reported for a silicon pFET. The transconductance is 1800uS/um. The technology is fully depleted silicon on insulator (FDSOI) with the pFET channel formed by SiGe condensation. This outstanding performance is achieved by a combination of layout and process optimization which minimizes capacitance and maximizes compressive strain on the channel. The technology features a high-k metal gate and short gate length (20nm drawn) in addition to the SiGe channel for high mobility.

CMOS RF performance gain by gate resistance optimization

We report experimental improvement of both RF and digital AC performance of a 28nm CMOS technology by predoping the gate poly. The results are explained in terms of the physical structure of the gate and the atomic structure of the gate TiN/Si interface in the gate stack.