Comparison of high voltage rectifier structures

A comparative analysis of the p-i-n, SSD (static shielding diode), SFD (soft and fast recovery diode), SPEED (self-adapting P-emitter efficiency diode), and MPS (merged P-N Schottky) rectifiers is performed using the two-dimensional numerical simulator MEDICI. Identical drift region properties are used to obtain the forward I-V, reverse I-V, and reverse recovery characteristics. The MPS, SSD, and SFD rectifiers are found to exhibit a much smaller stored charge and a shorter reverse recovery time than the other rectifiers. As the dose and depth of the shallow P-region implant is increased, the SSD rectifier characteristics are found to shift from those of the MOS rectifier to those of the p-i-n rectifier. It is concluded that the tradeoff between stored charge, leakage current, reverse recovery time, and forward voltage drop is best for the MPS and SSD rectifiers. These rectifiers also exhibit improved soft recovery during switching