4:45 PM - 5:00 PM
▲ [18p-Z05-12] Considerations on competition between SiC surface nitridation and etching at SiO2/SiC interface induced by high-temperature N2 annealing
Keywords:High temperature nitridation, SiC surface etching, SiC/SiO2 structure
The relationship between nitridation and surface etching at the 4H-SiC(0001)/SiO2 interface during high-temperature N2 annealing was investigated with AFM and XPS. Effects of SiO2 thicknesses, N2 annealing ambient and annealing durations on the nitridation efficiency as well as surface roughness were researched. The nitridation efficiency turns out to increase with the SiC surface roughening rate. It is indicated that not only excess oxidation at the SiC surface may hinder the nitridation process, but the surface etching speed decreases with the SiO2 thickness. These results show that a lower O2 partial pressure and thinner SiO2 condition are advantageous towards SiC surface nitridation, but both inevitably result in a gradual roughening of SiC surface.