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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$36\mu $ </tex-math></inline-formula>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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$8\mu $ </tex-math></inline-formula>m, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10\mu $ </tex-math></inline-formula>m, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$12\mu $ </tex-math></inline-formula>m, achieving an R<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\mathsf {\textbf {on,sp}}}$ </tex-math></inline-formula> of 9.5 m<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\cdot $ </tex-math></inline-formula>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.