Zn^+注入对p-GaN/Ni/Au欧姆接触特性的影响  

Influence of p-GaN/Ni/Au ohmic contact characteristics by Zn^+ implantation

作　　者：李鸿渐[1] 石瑛[1] 赵世荣[1] 何庆尧[1] 蒋昌忠[1] 

机构地区：[1]武汉大学物理科学与技术学院,湖北武汉430072

出　　处：《功能材料》2009年第6期946-948,952,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(10675094;10205010;10435060)

摘　　要：首次采用离子注入工艺研究金属电极和p-GaN的欧姆接触特性。Zn为Ⅱ族元素,可以提高p-GaN表面的载流子浓度,对p-GaN/Ni/Au(5/10nm)界面处进行Zn+注入。经Zn+注入后的样品在空气氛围中快速热退火处理5min,以减少离子注入带来的晶格损伤。研究发现Zn+注入改善了p-GaN/Ni/Au的欧姆接触特性,接触电阻率ρc从10-1Ω·cm2数量级降低到10-3Ω·cm2数量级。研究了不同Zn+注入剂量(5×1015、1×1016、5×1016cm-2)对接触电阻率的影响,在注入剂量为1×1016cm-2、300℃下退火得到最优的接触电阻率为1.45×10-3Ω·cm2。用扫描电子显微镜观察了离子注入前后的表面形貌变化,探讨了接触电阻率改变的内在机制。Ion implantation technology was firstly used on the study of the metal/p-GaN ohmic contact. As an Ⅱ element, Zn could improve the carrier concentration at the surface of p-GaN, so Zn＋ was implanted at the interface of p-GaN/Ni/Au （5/10nm）. To reduce the lattice damage brought by ion implantation, the sample was treated with rapid thermal annealing in air for 5 min. Investigation showed that metal/p-GaN ohmic contact characteristic got obviously improved, and specific contact resistance （pc） reduced from 10^-1Ω·cm^2 order to 10^-3Ω·cm^2 order. The effect of different implanted dose （5 × 10^15, 1 × 10^16, 5 × 10^16 cm^-2） on Pc was investigated, and the lowest p,（1.45×10^-3Ω·cm^2） was achieved after annealing in air at 300℃ for 5min with 1 × 10^16 cm^-2 Zn^＋ implantation. The change in the surface morphology of the contacts was observed using scanning electron microscopy, and the possible mechanism of the reduction of Pc was discussed.

关 键 词：P-GAN 欧姆接触 离子注入 退火 

分 类 号：TN304.2[电子电信—物理电子学]