Flexible photosensing devices

Abstract

Photodetectors(PDs) have many important applications in various fields; there is always a race to make them better and advanced. However, typical PDs are made of Si, GaAs, or some other semiconductors, and they are fragile. Recently, researchers discovered some inorganic-organic (hybrid) halide perovskite materials, which show enhanced parameters for optoelectronic applications. Since perovskites are flexible too, they fall into our main interest of making flexible photosensing devices. This M.Sc. project has two tasks, one is to fabricate a PD device on a flexible substrate and another is to deliver concept of proof of their application in real life. For the convincing of reader, we have divided our work into small sections. These sections contains a good amount of information about PDs, their working principle, and figures of merit. We also extended this introduction part to the perovskites. Then, we have discussed the characterization methods that are useful for our purpose. After that, we explained the experiments in greater detail, our failures, and our success and presented the corresponding data. We successfully fabricated a flexible PD, and in the last section, we have shown how it can be used as a Photoplethysmogram (PPG) device. This is an important aspect for wearable electronics and real time health monitoring device.