Thick junction photodiodes based on crushed perovskite crystal/polymer composite films

Abstract

Photodetectors based on organic–inorganic hybrid perovskites have emerged as prominent opto-electronic devices for next generation imaging and photodetection. Most of the thin film based devices suffer from poor device stability and large device capacitance. On the other hand, photodetectors based on single crystals have been reported as an alternative approach. However, single crystals are limited by the processing. In this work, we introduce a top down method to fabricate crushed perovskite crystal/polymer composite films. The prepared films possess synergestic advantages of single crystals and polymers, such as, enhanced material stability, maintenance of excellent charge transport and feasibility to prepare thick films. Prototypical thick junction photodiodes based on such composite films are fabricated. The devices presented decent photoresponse in the visible region, low dark current and noise, improved stability and compelling fast response of 800 ns. Benefiting from both large crystal size and composition engineering, the thick junction devices exhibited superior device stability with negligible degradation after 50 days’ storage and testing.