低p-GaN欧姆接触电阻的研究

The Research of Low Ohmic Contact Resistance to p-GaN

利用低压MOCVD系统,获得了p-GaN和p-InGaN/GaN超晶格结构2种材料,用圆形传输线模型(CTLM)测量了它们的比接触电阻率,并对表面处理、金属沉积和合金化处理的工艺条件进行了优化,得到了550℃、O2氛围下合金30min的最佳条件,获得最低的比接触电阻率为1.99×10-4Ω.cm2。

P-GaN bulk material and p-InGaN/GaN superlattice used as p-contact layer are grown by low pressure metal organic chemical vapor deposition（LP MOCVD）,and their specific contact resistivity（SCR） is measured by circular transmission line model（CTLM）. Meanwhile,surface pretreatment,metal deposion and annealing processes of ohmic contact on p-InGaN/GaN superlattice are optimized,and the best result with the SCR of 1.99 × 10^-4 Ω· cm^2 is achieved after annealing at 550 ℃ for 30 min in oxygen.