Nickel/6H-SiC欧姆接触机理研究

Investigation mechanism of nickel based ohmic contacts to 6H-SiC

通过XPS和XRD对500℃和950℃热处理后Nickel/6H-SiC接触层中C,O,Ni和Si元素的价电荷态进行了深入的研究.结果表明,950°热处理后转化为Ni2Si的合金相对实现好的欧姆接触起主要作用.在合金层中残留有大量的C原子,并且以石墨结构的C—C键结合形式存在.但实验中没有观察到石墨结构的纳米晶或晶体结构的石墨C层存在.

Abstract： The charge atate of C, Ni,O, Si in the contact layer of Nickel/6H-SiC, which after annealed at 950 ~C and 500 ~C respectively, when after thermal process at 950 ~C, Ni2Si is a dominant phase and plays a impor- tant role in determing the ohmic contact, accomany with a lot of carbons in this silicate layer, exist as graphite state C--C bond . but no nanocrystalline graphite or graphite layer film was observed in this experiment