200V Super Junction MOSFET Fabricated by High Aspect Ratio Trench Filling

In this paper, a new filling process using an anisotropic epitaxial growth was proposed as the fabrication method of a Super Junction (SJ) MOSFET. The anisotropic growth controlled with silicon (Si) and chlorine (Cl) source gases was applied to filling of the high-aspect-ratio trenches without voids. Using the process we succeeded in filling trenches with aspect ratio of 18, which is the highest aspect ratio works previously reported, and we fabricated a 200V SJ-MOSFET with a 2.7gm pitch trench gate structure. Consequently, the MOSFET showed electrical characteristics of the lowest on-resistance of 1.5 m-ohm-cm
²
and a breakdown voltage of 225V.