Design considerations and experimental analysis for silicon carbide power rectifiers

In this paper we present the investigation of properties of silicon carbide power rectifiers, in particular Schottky, PiN and advanced hybrid power re ctifiers such as the trench MOS barrier Schottky rectifier. Analysis of the forward, reverse and switching experimental characteristics are presented and these silicon carbide rectifiers are compared to silicon devices. Silic on carbide Schottky rectifiers are attractive for applications requiring bl ocking voltage in excess of 100 V as the use of Si is precluded by its larg e specific on-resistance. Analysis of power dissipation indicates that sili con carbide Schottky rectifiers offer significant improvement over silicon counterparts. Silicon carbide junction rectifiers, on the other hand, are s uperior to silicon counterparts only for blocking voltage greater than 2000 V. Performance of acceptor (boron) and donor (phosphorus) implanted experiment al silicon carbide junction rectifiers are presented and compared. Some of the recent developments in silicon carbide rectifiers have been described a nd compared with theory and our experimental results. The well established silicon rectifiers theory are often inadequate to describe the characterist ics of the experimental silicon carbide junction rectifiers and appropriate generalization of these theories are presented. Experimental trench MOS ba rrier Schottky rectifiers (TMBS) have demonstrated significant improvement in leakage current compared to planar Schottky devices. Performance of curr ent state-of-the-art silicon carbide rectifiers are far from theoretical pr edictions. Availability of high-quality silicon carbide crystals is crucial to successful realization of these performance projections. (C) 1999 Elsev ier Science Ltd. All rights reserved.