Design of non-uniform 100-V super-junction trench power MOSFET with low on-resistance

Abstract

The specific on-resistance of non-uniform super-junction (SJ) trench metal-oxide semiconductor field-effect transistor (TMOSFET) is superior to that of uniform SJ TMOSFET under the same breakdown voltage. For the desired blocking voltage with 100-V, the electric field varies exponentially with distance between the drain and the source regions. The idea with a linearly graded doping profile is proposed to achieve a much better electric field distribution in the drift region. The doping concentration linearly decreases in the vertical direction from the N drift region at the bottom to the channel one at the upper. The structure modeling and the characteristic analyses for doping density, potential distribution, and electric field are simulated by using of the SILVACO TCAD 2D device simulator, Atlas. As a result, the specific on-resistance of 0.66mΩ · cm2 at the class of 100V and 100A is successfully optimized in the non-uniform SJ TMOSFET, which has the better performance than the uniform SJ TMOSFET in the specific on-resistance. © IEICE 2012.