Quality and reliability of wet and dry oxides on n-type 4H-SiC

The thermal oxide on silicon carbide (SiC) is found to be subtly different from that grown on silicon and many basic oxide characterisation experiment s still remain to be carried out. Here a comparison is made between the bre akdown properties and wet and dry thermally grown oxides on n-type 4H-SiC o ver the temperature range 25-300 degrees C. The interface characteristics a re also compared for the two oxides. It was Found that for temperatures up to 200 degrees C the dry oxide could have more than an order of magnitude l arger charge to breakdown than that found for the wet oxide, whilst having no significant difference in interface state density or fixed oxide charge. At 300 degrees the breakdown mechanism changed and became process independ ent. Crown Copyright (C) 1999 Published by Elsevier Science S.A. All rights reserved.