表面氢化降低SiC/金属接触间界面态密度的机理

研究了SiC表面氢化降低界面态密度的机理。采用缓慢氧化、稀释的HF刻蚀、沸水浸泡的表面氢化处理方法，降低SiC表面态密度。该方法用于SiC器件的表面处理，在100℃以下制备了理想因子为1.20～1.25的6H-SiC肖特基二极管，其欧姆接触比接触电阻为(5～7)×10−3Ω·cm2。表面氢化处理的优点在于避免了欧姆接触
所需的800～1 200℃的高温合金，降低了工艺难度，改善了肖特基结的电学特性。The mechanism of lowering the density of interface states due to hydrogenating SiC surface was studied. The treatment of hydrogenation SiC surface by slowly oxidizing，etching by dilute HF and then immersing in boiling water was utilized to lower the density of surface states. The method was applied to treat the surface during fabricating SiC device. SiC Schottky diodes with ideality factor of 1.2～1.25 and ohmic contacts with specific resistance of (5～7)×10-3Ωcm2 were obtained below 100℃. Its advantages lay in avoiding the high-temperature annealing at 800～1 200℃ for conventional Ohmic contacts, decreasing technical difficulty, and improving the electric performances of SiC Schottky junction.