Sustainable Development Goals
Abstract/Objectives
Over past decades, near-infrared (NIR) photodetectors have become increasingly popular as they exhibit significant applications in telecommunication, astronomy, military, and biomedical fields. While traditional solutions for NIR photodetectors like group III-V compound semiconductors and HgxCd1-xTe systems show high sensitivity, a low cooling temperature is required during operation. Moreover, the fabrication of traditional NIR photodetectors is complex and costly. Therefore, this draws tremendous attention towards finding alternative solutions for NIR photodetectors. Based on the industrial point of view, metal oxides are stable, nontoxic, earth-abundant, and also cost-effective; thus they are a competitive candidate for next-generation photodetectors. This study aims to investigate the photo-response of the Cu–Mg–Ni–Zn–Mn oxide thin films with an additional element (Mn) contained in the compound to tune the bandgap value and improve the optical properties. Source: https://pubs.rsc.org/en/content/articlehtml/2021/tc/d0tc06117d
Results/Contributions

The nanocrystalline Cu–Mg–Ni–Zn–Mn (CMNZM) oxide thin films were successfully synthesized and deposited by RF sputtering. The Cu–Mg–Ni–Zn–Mn oxide thin films show a high absorption at 350–440 nm. From UV-Vis and UPS results, the as-deposited Cu–Mg–Ni–Zn–Mn oxide thin films reveal a bandgap of 1.96 eV, demonstrate characteristics of an n-type semiconductor, and possess a bandgap of 1.56 eV after 400℃-annealing. The UPS spectrum of the as-deposited Cu–Mg–Ni– Zn–Mn oxide indicates that the position of the valence band is 1.48 eV relative to its Fermi energy. Besides, the PL spectra show an energy gap of 2.78 eV, which is capable of electron emission. For the p+ -Si-substrate/Cu–Mg–Ni–Zn–Mn-oxide-thin-film/ ITO photodetectors, the best performance under 800 nm illumination occurs for that with as-deposited Cu–Mg–Ni–Zn– Mn-oxide, showing a responsivity of 0.62 A W-1 and EQE value of 96%, extracted at -2 V. Moreover, the as-deposited Cu–Mg–Ni–Zn–Mn oxide photodetectors demonstrated a competitive time response of tr = 13 ms and tf = 11 ms, which is faster than those of most previously reported thin film photodetectors. The above characteristic indicates that the Cu–Mg–Ni–Zn–Mn oxide thin film paves the way for developing high efficiency in photodetectors, especially from an industrial view, since it can be easily fabricated and tailored.

 

Source:

https://pubs.rsc.org/en/content/articlehtml/2021/tc/d0tc06117d

Keywords
Oxide thin-filmPhotodetectorSemiconductor
References