Lin P.-THuang W.-CLou Y.-QYan C.-YLin Y.-SChang C.-LChang P.-CGong J.-RHsueh W.-JWEN-JENG HSUEH2022-03-222022-03-22202100223727https://www.scopus.com/inward/record.uri?eid=2-s2.0-85109107480&doi=10.1088%2f1361-6463%2fac03e8&partnerID=40&md5=d394490973aa361605113399410afd53https://scholars.lib.ntu.edu.tw/handle/123456789/598329The electrical performance of thin-film transistors that use an amorphous oxide semiconductor (AOS) is significantly improved by incorporating metal cations as carrier suppressors. However, the effect of these elements on the performance of AOS-based photodetectors (PDs) is still unknown. This study uses a precursor containing lithium (Li) element and a sol-gel process to produce a Li-doped amorphous ZnSnO (a-ZTO) thin-film for UV PD applications. The results of x-ray photoelectron spectroscopy analysis show that the number of oxygen vacancies (V o) in a-ZTO thin-films decreases significantly from ?32.1% to ?14.4% after Li-doping (3 at%). The dark current decreases and the photocurrent increases in the ZTO-based PD so an ultra-high photo-to-dark current ratio (PDCR) of 1185 is achieved. The significant increase in PDCR means that solution-processed a-ZTO are eminently suited to use in UV PDs that use In-free AOSs. ? 2021 IOP Publishing Ltd.Li-dopingoxygen vacancysol-gelZnSnO photodetectorDark currentsIndium alloysIndium metallographyLithium metallographyOxide semiconductorsPhotocurrentsPhotodetectorsPhotonsSemiconducting zinc compoundsSemiconductor dopingSol-gel processThin film transistorsThin filmsX ray photoelectron spectroscopyAmorphous oxide semiconductorsDark current ratioElectrical performanceMetal cationMetal-semiconductor-metal uv photodetectorsPhotodetectors (PDs)Solution-processedUltra-highSemiconducting tin compoundsSolution-processed Li-doped ZnSnO metal-semiconductor-metal UV photodetectorsjournal article10.1088/1361-6463/ac03e82-s2.0-85109107480