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 (R_on) and gate-drain charge (Q_gd). In this structure, a trench gate pitch and a p/n column pitch can be independently controlled. We experimentally demonstrated a dependence of R_on and Q_gd on the orthogonal gate pitch. The experimental value of Ron*Qgd decreased with the increase of gate pitch, and this value of 0.16 OmeganC was achieved at the trench gate pitch of 10 mum and the p/n column pitch of 2.7 mum. 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 24 mJ/mm² and this result is 1.3 times stronger than that of conventional trench MOSFET.