Reduction of the power dissipation in silicon carbide Schottky rectifiers by a dual-metal planar structure

A dual-metal-planar rectifier on 6H-SiC was fabricated using Ti and Ni2Si as Schottky metals. The forward current voltage (I-V) characteristic of the dual-metal devices was comparable with that of Ti diodes. On the other hand, under reverse bias, almost the same leakage current of the Ni2Si rectifiers was achieved, i.e., a factor 1000 lower than that of Ti diodes. The fabricated diodes allowed to obtain a power dissipation of 0.37 W/cm(2), significantly reduced with respect to the Ti and Ni2Si diodes dissipation. Moreover, the breakdown voltage was the same as in the planar Ni2Si diode, thus indicating that the planar structure is very efficient in avoiding electric field crowding at the titanium stripes edges. (C) 2002 American Institute of Physics.