A Highly Efficient Annealing Process With Supercritical N2O at 120 °C for SiO2/4H-SiC Interface

A novel post-oxidation annealing (POA) process with supercritical N2O (SCN2O) fluid is reported to be highly effective in improving the interface properties of the SiO2/4H-silicon carbide (SiC) (0001) systems. After SCN2O POA, the interface state density reduces to 2.8 x 10(11) eV(-1)cm(-2), which is about 3.5 times lower than that after a traditional high-temperature N2O POA process. Meanwhile, the highest oxide critical electric field shows an increase of 18.19% and the near-interfacial oxide traps is reduced by 69.90% compared with that after N2O POA process. The process temperature is as low as 120 degrees C. The significantly reduced processing temperature avoids additional defect generation while the supercritical state provides a stronger nitridation effect. SCN2O annealing is a promising candidate for POA process toward high-performance SiC power metal-oxide-semiconductor field effect transistors (MOSFETs).

Automated summary

The novel post-oxidation annealing process with supercritical N2O fluid effectively enhances the interface properties of SiO2/4H-SiC systems, showing great potential for improving the performance of SiC power MOSFET devices.