Novel SiC accumulation-mode power MOSFET

In this paper, a new structure of Silicon Carbide (SiC) accumulation-mode MOSFET (ACCUFET) for high-power applications has been proposed and analyzed. The novel ACCUFET utilizes fully depleted N-channel epilayer, grown on P-base epilayer, to achieve normally-off operation. A trench region is formed by etching and is implanted to create N-type path that connects the N-channel epilayer (accumulation channel) to underlaying N-drift region. Detailed analysis of the important design parameters of the novel structure is performed using MEDICI two-dimensional (2-D) device simulator. The novel structure was also compared to alternative ACCUFET approaches, specifically planar and trench-gate ACCUFETs. The comparison shows that the novel structure provides the highest figure of merit (FOM) for power devices.