Elimination of current instability and improvement of RF power performance using Si3N4 passivation in SiC lateral epitaxy MESFETs

Abstract SiC lateral epitaxy (LE) MESFETs demonstrated a dramatic reduction of output conductance. Despite elimination of current injection into the substrate, a severe problem of current instability remained. Using PECVD Si 3 N 4 passivation, the current instability phenomenon has been completely eliminated resulting in improved RF power performance. RF output power measured after passivation exceeded 90% of the theoretical maximum values that were derived from the DC characteristics. Further enhanced performance in class B operation was observed.