A vertical super-junction strained-silicon channel power MOSFET

In this paper, we propose a vertical super-junction strained-Si channel power MOSFET to improve the breakdown voltage, drain current, threshold voltage, and transconductance. In the proposed structure, a P-pillar forming super-junction with N-drift region is incorporated to get higher blocking voltage due to reduction in electric field inside the drift region. In order to lower the on-resistance, the proposed device uses a strained-Si channel which is created with the help of a relaxed Si0.8Ge0.2 layer over a compositionally graded Si1-xGex buffer. This also increases the current drivability, reduces the threshold voltage and enhances the transconductance. Based on 2D simulations, the proposed MOSFET is shown to achieve 37% improvement in breakdown voltage, 44% increase in driving current, 60% reduction in threshold voltage, and 22% improvement in peak transconductance as compared to the conventional power MOSFET.