Low-temperature processed high-performance visible–transparent Ga 2 O 3 solar blind ultraviolet photodetectors with the indium–tin–oxide electrode

Abstract High-performance visible–transparent electronics are being used as emerging technologies in next-generation ‘see-through’ devices. In this work, the high-performance fully visible–transparent metal–semiconductor-metal (MSM) interdigitated Ga 2 O 3 solar blind ultraviolet (UV) photodetector (PD) was successfully fabricated by using the ITO electrode. The Ga 2 O 3 film and the ITO electrode were grown on the sapphire substrate by the radio frequency magnetron sputtering method at a low temperature. It is demonstrated that the Ga 2 O 3 film is the single crystal film with the (−201) crystal plane orientation, and its bandgap can be obtained around 4.8 eV. Compared with the control tradsitional opaque PD with the Ti/Au metal electrode, the fully visible–transparent solar blind UV PD with the ITO electrode showed a larger photocurrent of 1.8 µ A and responsivity of 181.03 A W −1 at the bias voltage of 20 V. The external quantum efficiency (EQE) even reached 88 198%, and photo-to-dark current ratio achieved 4.8 × 10 5 . Besides, the PD with the ITO electrode also had a shorter response time and good electrical stability after multiple light cycles. The fabricated fully visible–transparent Ga 2 O 3 solar blind UV PD is among the best reported Ga 2 O 3 UV PDs and shows the great potential for the next generation of ‘see-through’ functional devices.