Experimental characterization of a 4H-SiC high voltage current limiting device

The aim of this paper is to show the first experimental results of a 600 V 4H-SiC current limiting device. This device limits the current which flows through it as the bias voltage between its two contacts increases. The static curves obtained from the first process run (T = 300K) show a current limitation capability with a saturation voltage ranging from 10 to 15 V. The device electrical characterization shows a R-ON approximate to 150 m Omega cm(2) and a current density of 150 A cm(-2) under 50 V. The forward conduction is ensured by an N type implanted channel (doping species: nitrogen) on top of an P+ implanted layer (doping species: aluminum). The post-implantation annealing of 1700 degreesC/30 min leads to a good electrical activation (80%) of the N-channer/P+ layer (analyzed by C(V) and SIMS methods) and a good channel mobility (100 cm(2) V-1 s(-1) for a 2 x 10(17) cm(-3) N compensated doping concentration). The prototypes of the second process run reach a saturation current density of 900 A cm(-2) with a specific on-resistance of 13 m Omega cm(2). The 4H-SiC current limiting devices of the second run belong to the best set of Accu-MOSFETs devices reported in the literature. (C) 2001 Elsevier Science B.V. All rights reserved.