5-kV SiC Deep-Implanted Superjunction MOSFETs

This work presents the development and characterization of 5kV deep-implanted SiC superjunction (SJ) MOSFETs. In these switches, the $36\mu $ m deep n-type and p-type SJ pillars were formed using three rounds of epitaxial overgrowth and ultra-high-energy implantation (UHEI). We successfully fabricated SJ MOSFETs with pillar pitches of $8\mu $ m, $10\mu $ m, and $12\mu $ m, achieving an R $_{\mathsf {\textbf {on,sp}}}$ of 9.5 m $\Omega $ $\cdot $ cm2 at room temperature, which is 25% below the SiC unipolar limit. The devices also demonstrated sharp avalanche breakdown at 5.1kV with low leakage current density.