Rapid thermal-treated transparent electrode for photodiode applications

•Heterojunction photoelectric device provided extremely high photo-responses.•Thermal treatment affects the solid-state oxidation reaction of ITO and Si.•An oxide interface determines a rectifying junction quality.

We demonstrate a high performing and cost-effective photodiode with a low thermal budget. A quality heterojunction photoelectric device provided extremely high photo-responses. Transparent conductive indium-tin-oxide (ITO) film was coated on a Si substrate at a room temperature and then, rapid thermal treatment was done at 300 °C for 10 min. This heterojunction (ITO/Si) spontaneously provides a rectifying junction that shows high photo-response values of 1920%, 3240%, and 2800% at wavelengths of 350 nm, 600 nm, and 1100 nm, respectively. Thermal treatment affects the solid-state oxidation reaction of ITO and Si and control the formation of an interfacial layer.