Enhanced Charge Carrier Mobility of Evaporated Sb2Se3 via Post‐Treatment for High‐Speed Photodetection

Abstract Benefiting from excellent optoelectronic properties and facile fabrication, Sb 2 Se 3 ‐based semiconductor devices have drawn great attention in the last decade; in particular, Sb 2 Se 3 ‐based solar cells and photodetectors have demonstrated decent performance metrics. However, the current research on Sb 2 Se 3 devices is mainly focused on material and device processing and optimization, and few studies have been conducted on charge transport, which is limiting the further development of Sb 2 Se 3 ‐based devices. To address this issue, post‐treatment techniques are introduced and their influence on the charge carrier dynamics of Sb 2 Se 3 thin films is fully investigated. The charge carrier mobility of evaporated Sb 2 Se 3 thin films is increased by an order of magnitude from 0.02 to 0.4 cm 2 V −1 s −1 after the Se post‐treatment. Based on the optimized Sb 2 Se 3 thin films, ultra‐fast photodiodes are further developed and a record‐fast response of 37 ns is achieved. Prototypical devices also demonstrated great potential for high‐speed photodetection in practical applications.