Demonstration of n-Ga<sub>2</sub>O<sub>3</sub>/p-GaN Diodes by Wet-Etching Lift-Off and Transfer-Print Technique
Yang Liu, Lai Wang, Yuantao Zhang, Xin Dong, Xiankai Sun, Zhibiao Hao, Yi Luo, Changzheng Sun, Yanjun Han, Bing Xiong, Jian Wang, Hongtao Li
Abstract
In this letter, a 400-nm-thick β-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> nanomembrane is extracted from an n-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> -on-silicon wafer by wet etching, and then transferred to a p-GaN/ sapphire wafer by transfer-print technique to fabricate n-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> /p-GaN heterojunction diodes. X-ray photoelectron spectroscopy (XPS) measurement is used to accurately confirm that the valence-band offset of the heterojunction is 1.41± 0.07 eV. The diodes exhibit excellent electrical properties including high rectification ratio ( 3.85×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> at ±5 V) and low reversed current density ( 1.51×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-7</sup> A·cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> at -5 V). The results show that the lift-off and transfer-print processes pave a new way for fabricating high-performance 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> -based heterojunctions and bipolar devices.