Super high-speed self-powered photodetector based on solution-processed transparent p-type amorphous phosphorous-doped SnO film

It is challenging to simply prepare high-performance optoelectronic p-type oxide semiconductors because their strong hole localization makes it difficult to generate mobile hole carriers. In this study, amorphous transparent p-type SnO films were prepared in a glove box using a simple solgel method. Phosphorus (P) doping improves the optoelectronic properties of the SnO films and their corresponding self-powered heterojunction photodetectors. The response time of the self-powered heterojunction photodetectors based on P-doped SnO (P-SnO) is 40.29 µs/76.24 (0 V bias), which is the fastest among other p-type oxide-based photodetectors. The P-SnO photodetector also possesses the fastest decay time compared with typical n-type amorphous gallium oxide photodetectors. Introducing impurity energy levels through P doping is responsible for the increase in photogenerated electron-hole pairs and photocurrent and device performance enhancement. This work not only provides a simple method for preparing high-performance and low-cost p-type P-SnO films and photodetectors, but also offers a new approach for improving the performance of various p-type oxide semiconductors and devices.