New Technology to Improve Sic Power Equipment

High-performance power equipment is usually used in high-pressure, large current and high frequency equipment. It is effective in energy conservation. Especially Sic equipment that consumes far less energy than traditional silicon equipment. However, due to Sic gate insulation layer intrinsic flaws, Sic transistor resistance is high and not stable, which influences its performance. Gate insulation layer flaws is caused by Sic interface impurities and atom excess or insufficiency.

Professor Koji Kita in Engineering Institute of Tokyo University has discovered that while producing gate insulation layer film, by-product carbon can act as CO to decrease interface flaws density. Researchers experimented the principle on metal-oxide-semiconductor structure and received the lowest interface flaws in density.

(Left) Schematic of oxidation of SiC/SiO2 interface. The desorption of byproduct carbon as carbon monoxide is an effective way to reduce interface defect formation. (Right) Interface state density of 4H-SiC/SiO2 observed in this study, compared with previously reported typical values (hatched areas). The horizontal axis shows the energy levels of defect states referred to the conduction band edge of SiC.

This technology has avoided extra processing procedure while improving Sic surface performance, so it is easy to handle; it has achieved a huge step in energy conservation of electric power transmission, electric vehicles and factory machinery equipment.