Bandgap Engineering of AlxZn1-xO Deposited by Mist Chemical Vapor Deposition for Photodetector Applications: From UV-A to UV-C

study investigates metal- semiconductor-metal ultraviolet (UV) photodetectors (PDs) based on Al0.1Zn0.9O, Al0.3Zn0.7O, and Al0.5Zn0.5O deposited using the mist chemical vapor deposition. The material analyses indicate that the higher Al content degrades the crystallinity, reduces oxygen vacancy, and increases the energy bandgap of the AlxZn1-xO. The cutoff wavelengths of Al0.1Zn0.9O-, Al0.3Zn0.7O-, and Al0.5Zn0.5O-based PDs, respectively, are 358, 309, and 269 nm, and each of their maximum responsivity is 342.22, 12.19, and 0.73 A/W. It is worth mentioning that the cutoff wavelengths of Al0.1Zn0.9O-, Al0.3Zn0.7O-, and Al0.5Zn0.5O- based PDs are located in UV-A, UV-B, and UV-C regions. The UV-to-visible rejection ratios for the Al0.1Zn0.9O-, Al0.3Zn0.7O-, and Al0.5Zn0.5O-based PDs are 1.7 x 10(4), 2.3 x 10(4), and 5.7 x 10(4). These results suggest that the bandgap engineering is available for the present AlxZn1-xO thin films, making them suitable to detect deep-UV irradiation.

Automated summary

This study investigates metal-semiconductor-metal ultraviolet (UV) photodetectors based on AlxZn1-xO thin films prepared by mist chemical vapor deposition. The results show that the crystallinity, oxygen vacancy, and energy bandgap of the films are affected by the Al content. The PDs based on Al0.1Zn0.9O, Al0.3Zn0.7O, and Al0.5Zn0.5O exhibit different cutoff wavelengths and maximum responsivity, making them suitable for deep-UV detection.