Fabrication and Measurement of Cosputtered Indium Gallium Oxide Ultraviolet Photodetectors

Indium gallium oxide (IGO) ultraviolet (UV) photodetectors (PDs) were fabricated by cosputtering. The power of the gallium oxide target was fixed at 80 W, while the power of the indium oxide target was varied at 20, 30, 40, and 80 W. As the amount of indium doping increased, the dark current and response decay time increased. Furthermore, the sensitivity and responsivity of the PDs also increased, reaching the maximum values of 5.20 × 10³ at 30 W/80 W and 1.72 × 10² A/W at 40 W/80 W, respectively. However, excessive indium doping resulted in excessively high dark current and increased sensitivity and response decay time. Therefore, proper control of indium doping can lead to high-performance IGO UV PDs.