Abstract:
The quest for flexible and completely visible transparent solar-blind photodetector is the great
motivation for next generation invisible security and photo-sensor application. Here, we have
developed high performance and completely flexible solar blind photodetector using room
temperature grown amorphous Ga2O3 thin film and unconventional amorphous indium-zincoxide (a-IZO) transparent conducting electrodes. The a-IZO transparent conducting electrodes
are deposited using an optimized and unique RF superimposed DC sputtering which helps
to achieve high optoelectronic properties with excellent mechanical flexibility. In contrast to
conventional and highly reflective silver (Ag) metal electrodes, IZO offers transparency >85%
in visible-IR. The solar-blind photodetector with a-IZO electrode shows high responsivity of
43.99 A W−1
and high external quantum efficiency of 2.18 × 104
% in contrast to conventional
Ag metal electrodes. The performance of the a-IZO/a-Ga2O3 photodetector is the highest
among the reported amorphous Ga2O3 photodetector. Moreover, the flexibility of a-IZO
electrode and conventional Ag metal electrode on a-Ga2O3 photodetector is investigated
under repeated bending cycle. The a-IZO electrode shows excellent flexibility of the solarblind photodetector and demonstrated a decrease in photocurrent by 28.6% under 30 cm
bending radius and a 38.8% decrease in photocurrent even after 500 stretch/release cycles
at 30 cm bending radius. However, the conventional Ag electrode shows complete failure on
bending with 30 cm bending radius even on single cycle. The results demonstrated a-IZO thin
film as a potential electrode for next generation flexible and visible transparent solar-blind
photodetector
