Fabrication and characterization of MOSCAP on bulk beta-gallium oxide substrate with ALD silicon dioxide
Beta-gallium oxide (beta-Ga 2 O 3 ) has recently attracted a lot of attention because of its very high Baliga's figure of merit (BFOM), which indicates a good application prospect for it in the field of power electronics. Its high breakdown field and low cost makes it very attractive, but the low thermal conductivity and low mobility hinder its performance improvement. MOSFET with ALD Al 2 O 3 gate dielectric has been successfully fabricated and reported. In this thesis, we investigated an alternative choice for gate dielectric - ALD SiO 2 . This new dielectric not only offers bigger conduction band offset, but also gives a very nice interface property. And both of them are very important for improving the performance of power devices. MOSCAPs are fabricated using several special techniques to study the properties related to this new oxide. Conduction band offset, oxide trap density and interface trap density are extracted using a few IV and CV methods.