High voltage Ni/4H-SiC Schottky rectifiers

Abstract

In this paper, we report characteristics of 4H-SiC Ni/Al Schottky rectifiers operating at 1.5 to 2.5 kV and terminated using low energy Ar implants. At room temperature, the nickel Schottky diode exhibited a barrier height of 1.7 eV and an ideality factor of 1.07. After annealing, the Schottky diode fabricated on a 20 /spl mu/m thick epilayer had a forward voltage drop of 1.16 V at 100 A/cm/sup 2/, the lowest value ever reported for a 1.6 kV rectifier. A breakdown voltage of >2500 V was measured on diodes fabricated using 40 /spl mu/m epilayers. The measured specific on-resistance of 20 /spl mu/m and 40 /spl mu/m epi diodes was within /spl sim/1.5/spl times/ of the calculated drift region resistance over a 0-200/spl deg/C temperature range.