The influence of body effect and threshold voltage reduction on trench MOSFET body diode characteristics

Abstract

This paper presents a comprehensive study of the body diode characteristics of high-channel density trench power MOSFETs using analytic modeling, 2-dimensional numerical simulation, and physical measurements. The results show that, for state-of-the-art trench MOSFETs, the body diode characteristics are strongly influenced by majority carriers in the channel due to gate-controlled third quadrant conduction. This large channel current is shown to be the result of dynamic threshold voltage lowering due to the MOSFET body effect.