A Novel Dual Gate Strained-Silicon Channel Trench Power MOSFET For Improved Performance

In this paper, we propose a new dual gated trench power MOSFET with strained Si channel using the Si0.8Ge0.2 base and graded strained Si accumulation region using compositionally graded Si1-xGex buffer (x varying from 0 to 0.2 from the drift region to the base region) in drift region. We show that the introduction of strain in channel and accumulation region results in about 10% improvement in its drive current, about 20% reduction in the on-resistance and about 72% improvement in peak transconductance with only about 12% reduction in the breakdown voltage when compared with equivalent conventional device. Furthermore, the structure contains two separated gates out of which one controls the inversion charge in the channel region and the other one controls the accumulation charge in the accumulation region. The separate control of the charge in different regions further improves the device performance. We show that by applying a suitably high fixed positive voltage at the accumulation gate improves the device performance parameters up to about 10%.