Quasi-SOI MOSFET: a novel architecture combining the advantages of SOI and bulk devices
In this paper, a novel structure named as quasi-SOI MOSFET is proposed, which can combine the advantages of both SOI structure and bulk structure. In the quasi-SOI structure, the source/drain regions are quasi-surrounded with insulator and the channel region is directly connected with the bulk substrate. Short channel effects (SCE), parasitic capacitance and self-heating effects (SHE) can be well alleviated. A method to fabricate the quasi-SOI MOSFET is also put forward and realized by process simulation. Quasi-SOI devices can be realized with a channel formed by epitaxial technology and a buried oxide layer formed by thermal oxidation. Simulation results show good scaling capability and excellent heat dissipation. The drive current and the leakage current can be adjusted by changing the substrate doping for specific applications. Cut-off frequencies as high as 220 GHz for NMOS and 130 GHz for PMOS at 20 nm effective channel length (Leff) can be obtained according to process simulation results.