EFFECT OF POST-DEPOSITION ANNEALING IN FORMING GAS ON STRUCTURAL AND ELECTRICAL PROPERTIES OF SOL–GEL DERIVED SiO2 THICK FILM ON 4H–SiC

Abstract

The effect of post-deposition annealing in forming gas on the structural and electrical properties of sol–gel derived SiO 2 thick film on n-type 4H–SiC has been systematically investigated. Tetraethylorthosilicate-based precursor with H 2 SO 4 as catalyst was prepared and prior to film deposition, substrate surface was treated by hexamethyldisilizane. The spin-coated film was annealed at 750–950°C for 30 min with an approximately 185-nm thick film. It was found that oxide annealed at the highest temperature revealed the densest film, lowest oxide defects, and lowest total interface trap density. As a result, this oxide had demonstrated the lowest leakage current density if compared with other oxides.