Forward Current Conduction Mechanism of Mechanically Exfoliated <i>β</i>-Ga<sub>2</sub>O<sub>3</sub>/GaN pn Heterojunction Diode
Qian Feng, Guangshuo Yan, Zhuangzhuang Hu, Zhaoqing Feng, Xusheng Tian, Dian Jiao, Wenxiang Mu, Zhitai Jia, Xiaozheng Lian, Zhanping Lai, Chunfu Zhang, Hong Zhou, Jincheng Zhang, Yue Hao
Abstract
In this letter, we fabricated the mechanically exfoliated β-Ga2O3/GaN pn heterojunction diode and carried out the electrical characteristics measurements. At room temperature, the diode shows a good rectifying property, with a turn-on voltage of 3.9 V–4.6 V and rectifying ratio greater than 106 @ ±20 V. From the 1/C2 vs V plot, the built-in voltage is determined to be 3.4 V and the energy band diagram of the heterojunction is also constructed. According to the temperature dependent I-V cures, three different forward current conduction mechanism can be identified, recombination-tunneling mechanism, trap charge limited space-charge-limited-current(SCLC) and SCLC mechanism for I < 10−7 A (region I), 10−7 < I < 10−4 A (region II) and I > 10−4 A (region III), respectively. While in region II, two different Et from exponential trap distribution model is determined to be 0.514 eV, 0.310 eV and the corresponding trap density is 1.63 × 1016 cm−3 and 1.71 × 1016 cm−3, respectively.