Numerical Analysis of Local Lifetime control for High-speed low-loss PiN diode design

The effect of localized lifetime control technique on the static and dynamic behavior of power PiN diode is investigated in the paper. Mixed mode device circuit simulations are used in order to analyze the effect of the width and of the position of a reduced lifetime region on the diode. The simulations show that the optimal position for the low-lifetime region is at the beginning of the base region on the anode side, while the optimal width of the low lifetime region depends on the amount of lifetime reduction. The local lifetime control design technique is shown to be effective in reducing the turn-off time and increasing diode softness with a little worsening of on-state voltage drop. It is shown that the trade-off curve obtained by diodes using local lifetime control is better than the one achieved with lifetime killing in the whole epilayer region.