Gate oxides on 4H-SiC substrates grown or annealed in N2O/Ar mixture

N₂O directly grown gate oxides on 4H-SiC have been characterized using MOS capacitors, under several diluted N₂O/Ar furnace conditions. The effect of N₂O annealings on standard thermal dry O₂ gate oxides has also been analysed comparing the channel mobility of 4H-SiC MOSFETs. The measured 4H-SiC MOSFET transfer characteristics are fitted using a 2D device simulator (MEDICI), taking into account the effect of the interfacial traps density within the band-gap.