ZnO/Ga₂O₃ Optoelectronic Device with Wide Response Wavelength

Heterojunction optoelectronic devices have always been a research hotspot. In this paper, ZnO/Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> heterojunction thin films are used to form optoelectronic devices with Ni metal. A 100nm ZnO thin film is magnetron sputtered on a sapphire substrate, then, a 300nm Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> material is deposited on the ZnO thin film by magnetron sputtering. The high-quality Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> thin films were obtained by using ZnO as the substrate. After depositing Ni metal electrodes on Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> thin films, ZnO/Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> photodetection device is formed. The device has a photoresponse current of more than 10 times than the dark current under a bias of 5V. And this device has a photoresponse time of 1.1s and a relaxation time of 1s, respectively. Compared with ZnO thin film optoelectronic device, ZnO/Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> device has a wider spectral response and higher photoresponsivity at the same wavelength. This work provides a theoretical and practical basis for the growth of oxide heterojunctions, and has reference significance for the later research of heterojunction thin film devices.