Novel SiC/Si Heterojunction Power MOSFET With Breakdown Point Transfer Terminal Technology by TCAD Simulation Study

The novel SiC/Si heterojunction power MOSFET has been advanced to improve the tradeoff between the breakdown voltage (BV) and specific on-resistance (R-ON, sp). The innovative terminal technology of breakdown point transfer has been applied to SiC/Si MOSFET, which transfers the breakdown point from the high electric field points to the low electric field areas and improves the BV compared with the conventional Si power MOSFET. The results have been shown by technology computer aided design simulation that the BV has been improved for SiC/Si U-MOSFET due to PBT technology. The BV of the proposed SiC/Si U-MOSFET is increased to 358 V compared with the Si U-MOSFET of 107 V with the same device parameters. The simulatedRON, sp of the SiC/Si U-MOSFET is 0.51 m Omega . cm(2) with the BV of 358 V, which is lower than that of 1.12 m Omega . cm(2) with the BV of 107 V for the conventional Si U-MOSFET. The important law is discovered that the high BV and low R-ON, sp can be obtained simultaneously for SiC/Si U-MOSFET when the depth of the trench oxide layer is increased, which cannot be taken into account in the conventional Si U-MOSFET. Therefore, the silicon and superjunction VDMOS (double-diffused MOSFET) limits had been broken for SiC/Si U-MOSFET. The influences of the different interface charge (acceptorlike and donorlike) have been analyzed for SiC/Si VDMOS and SiC/Si U-MOSFET.