On the reverse leakage current of Schottky contacts on free-standing GaN at high reverse biases

• 作 者: 雷勇 苏静 吴红艳 杨翠红 饶伟锋
• 机 构: Department of Materials Physics,School of Physics and Optoelectronic Engineering,Nanjing University
• 出 处: Chinese Physics B
• 发表日期: 2017年02期
• 关键词: Schottky leakage tunneling contacts dominated explain conductive dislocation fit

In this work, a dislocation-related tunneling leakage current model is developed to explain the temperature-dependent reverse current–voltage(I–V –T) characteristics of a Schottky barrier diode fabricated on free-standing GaN substrate for reverse-bias voltages up to-150 V. The model suggests that the reverse leakage current is dominated by the direct tunneling of electrons from Schottky contact metal into a continuum of states associated with conductive dislocations in GaN epilayer.A reverse leakage current ideality factor, which originates from the scattering effect at metal/GaN interface, is introduced into the model. Good agreement between the experimental data and the simulated I–V curves is obtained.

In this work, a dislocation-related tunneling leakage current model is developed to explain the temperature-dependent reverse current-voltage (I-V -T) characteristics of a Schottky barrier diode fabricated on free-standing GaN substrate for reverse-bias voltages up to-150 V. The model suggests that the reverse leakage current is dominated by the direct tunneling of electrons from Schottky contact metal into a continuum of states associated with conductive dislocations in GaN epilayer. A reverse leakage current ideality factor, which originates from the scattering effect at metal / GaN interface, is introduced into the model. Good agreement between the experimental data and the simulated I-V curves is obtained.