1200 V, 50 A Trench Oxide PiN Schottky (TOPS) diode

A novel high voltage rectifier, called the Trench Oxide PiN Schottky (TOPS) rectifier, is described in this paper. The TOPS rectifier is a synergistic combination of a Schottky rectifier and a P ⁺iN diode, using a trench oxide structure to achieve high aspect ratio P+ regions, which permits a superior trade-off between forward voltage drop and switching characteristics, as compared with SSD (Static Shielding Diode), P^--i-N, and P⁺-i-N rectifiers, white maintaining an excellent blocking capability. A reverse leakage current of 100 nA was measured at 1200 V for a high current TOPS rectifier (die area=0.5 cm²), which is comparable to that in a P⁺IN diode. TOPS rectifiers with different Schottky/P⁺ ratios, SSD, P^--i-N, and P ⁺-i-N rectifiers were fabricated using punch-through (EPI) wafers. The reverse recovery characteristics of the TOPS rectifier has a much smaller peak reverse recovery current I_RP than those in the SSD and P⁺-i-N rectifiers. The stored charge Q_rr in the TOPS rectifier is smaller than that in the P^--i-N rectifier