A Novel Power PiN Diode with p-type Schottky Anode and Trench Oxide for Improving Reverse Recovery

A novel power diode with p-type schottky anode and trench oxide is proposed. The p-type schottky anode is able to reduce the reverse recovery charge (Q
rr
). The trench oxide regions with n-rings separate n
⁺
cathode regions from p-type cathode (pc) regions. The n-rings stop the electric field to ensure a fluent electron leakage current path from the n
⁺
cathode region to n-rings in the blocking state, which eliminates the effect of pc regions on the breakdown voltage (V
B
). Moreover, pc regions can inject holes into the n-drift region during reverse recovery, which helps to obtain soft reverse recovery. Simulations of 1300 V designs show that the proposed PiN diode is able to reduce Q
rr
by 50% and effectively suppress electrical oscillations during reverse recovery.