Effect of Deposition Temperature on the Characteristics of Ga2O3 Films Grown on Flexible Mica and the Performance of Corresponding Photodetectors

In this study, we fabricated flexible Ga2O3 photodetectors (PDs) based on Ga2O3/mica flexible structures obtained at different substrate temperatures. Higher substrate temperatures result in higher quality crystals for the film, but they also reduce the photoresponsivity of the PD. Meanwhile, the dark current of the PD gradually decreases, and the response time is significantly shortened. The PD fabricated at 440 °C exhibited a responsivity of 4.45 W/A at 20 V bias and weak UV illumination of approximately 380 μW/cm2 (at 254 nm). It also demonstrated a high detectivity (D*) of 6.07 × 1012 Jones and an extremely low noise equivalent power (NEP) of 4.42 × 10–13 W/Hz1/2. At 680 °C, the PD exhibits an extremely low dark current (1.6 × 10–13 A at 20 V) and a fast response time (τrise: 0.89 s, τdecay: 0.26 s). Additionally, in bending tests, the PDs maintained nearly constant performance, demonstrating excellent flexibility and revealing the potential applications of Ga2O3 flexible PDs in future wearable electronics.