Effects of Re-oxidation on the Electrical Properties of Wet Oxide Grown on C-face of 4H-SiC

摘要

We have studied the effect of wet re-oxidation on SiO_2 films grown on the C-face of 4H-SiC. The metal oxide semiconductor (MOS) capacitors exhibit oxide charge density on the order of 10~(12) cm~(-2) and interface trap density (D_(it)) between 2-7Xl0~(12) cm~(-2)ev~(-1). Unlike oxides grown on the Si-face, re-oxidation in steam for 10 min between 500° and 1000℃ and for 5 hr at 500℃ does not significantly change these characteristics. Similar to MOS samples that utilize the Si-face, both as-grown and re-oxidized C-face samples exhibit an increase in D_(it) near the conduction band (CB) edge.