200V Trench Filling Type Super Junction MOSFET with Orthogonal Gate Structure

A Super Junction (SJ) MOSFET which trench gates are orthogonal to p/n columns was fabricated to improve a tradeoff relationship between specific on-resistance (Ron) and gate-drain charge (Qgd). In this structure, a trench gate pitch and a p/n column pitch can be independently controlled. We experimentally demonstrated a dependence of Ron and Qgd on the orthogonal gate pitch. The experimental value of Ron*Qgd decreased with the increase of gate pitch, and this value of 0.16ΩnC was achieved at the trench gate pitch of 10μm and the p/n column pitch of 2.7μm. This figure-of-merits (FOMs) value is about 36% lower than that of the previous reported for 200V SJ-MOSFETs. Moreover, the undamped inductive switching (UIS) endurance of this SJ-MOSFET was 24mJ/mm
²
and this result is 1.3 times stronger than that of conventional trench MOSFET.