氧等离子体处理提高AlGaN/GaN肖特基势垒高度  

Improvement of AlGaN/GaN Schottky Barrier Height by Oxygen Plasma Treatment

作　　者：赵勇兵 Zhao Yongbing(School of Physics and Electronics Engineering,Yancheng Teachers University,Yancheng 224007,China)

机构地区：[1]盐城师范学院物理与电子工程学院,江苏盐城224007

出　　处：《半导体技术》2020年第10期760-763,815,共5页Semiconductor Technology

基　　金：国家自然科学基金资助项目(61904158)。

摘　　要：通过氧等离子体处理工艺,在AlGaN/GaN异质结构上制备了肖特基二极管。基于正向电流-电压特性和双二极管模型,对AlGaN/GaN异质结构的肖特基势垒高度和理想因子进行了计算和分析。采用氧等离子体处理的肖特基二极管,其理想因子由4.7下降到1.45,势垒高度由0.8 eV提高到1.057 eV,反向漏电流降低了约两个数量级。经氧等离子体处理制备的AlGaN/GaN肖特基二极管具有较高的势垒高度,抑制了垂直隧穿,同时氧等离子体处理对肖特基接触金属下方和附近的表面陷阱还起到钝化作用,从而降低了陷阱辅助隧穿。氧等离子体处理工艺为制备理想的肖特基二极管提供了一种有效的方法。Schottky diodes were fabricated on AlGaN/GaN heterostructure by oxygen plasma treatment process. Based on the forward current-voltage characteristics and the double-diode models, the Schottky barrier height and ideal factor of AlGaN/GaN heterostructure were calculated and analyzed. For the Schottky diodes treated with oxygen plasma, the ideal factor value decreases from 4.7 to 1.45, and the barrier height increases from 0.8 eV to 1.057 eV. The reverse leakage current of AlGaN/GaN Schot-tky diode is reduced by about two orders of magnitude.The AlGaN/GaN Schottky diodes treated by oxygen plasma have a high barrier height, which restrain the vertical tunneling. The oxygen plasma treatment has passivated the surface traps under and near the Schottky contact metal, thus reducing the trap assisted tunneling. The oxygen plasma treatment process provides an effective method for the preparation of an ideal Schottky diode.

关 键 词：ALGAN/GAN 肖特基二极管 势垒高度 氧等离子体处理 理想因子 

分 类 号：TN304.26[电子电信—物理电子学] TN311.7