Silicon planar ACCUFET: improved power MOSFET structure

An improved power MOSFET structure in silicon. Called the planar ACCUmulation channel field effect transistor (planar ACCUFET) is proposed. In this device, the P base and the deep P⁺ regions of the conventional DMOSFET are replaced by a depleted N-type base region created using a buried P⁺ region. Numerical simulations show that the planar ACCUFET has good forward blocking characteristics with low leakage current. The specific on-resistance, as well as the gate charge of the planar ACCUFET are lower than those of a DMOSFET with the same voltage rating. Furthermore, the planar ACCUFET requires a smaller thermal budget for fabrication than the DMOSFET