Design and Fabrication of Vertical Metal/TiO<sub>2</sub>/β-Ga<sub>2</sub>O<sub>3</sub>Dielectric Heterojunction Diode With Reverse Blocking Voltage of 1010 V
Zhuangzhuang Hu, Jianguo Li, Chunyong Zhao, Zhaoqing Feng, Xusheng Tian, Yanni Zhang, Yachao Zhang, Jing Ning, Hong Zhou, Chunfu Zhang, Yuanjie Lv, Xuanwu Kang, Hao Feng, Qian Feng, Jincheng Zhang, Yue Hao
Abstract
This work provides insight into the design principles and the reasonable construction of Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> heterojunction diode. We chose TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> grown by atomic layer deposition (ALD) as a suitable insulator with a small conduction band offset of TiO<;span style="font-size: 14.5px;"> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /<;/span> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">β</i> -Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> heterojunction and a large dielectric constant. The type-I band alignment of the TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> / <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">β</i> -Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> heterojunction was obtained using X-ray photoelectron spectroscopy (XPS). We demonstrated a high-performance vertical metal/TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> / <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">β</i> -Ga <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> dielectric heterojunction diode with reverse blocking voltage of 1010 V and differential ON-resistance of 3.3 mΩ·cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The proposed design principles of dielectric heterojunction diode and the insulator selection can also provide a simple, effective, and feasible technology for other wideband and ultrawideband semiconductors in which bipolar doping is challenging to achieve high power device performance.