High Performance Photodetector Based On The Heterojunction Of Si Nanowire Arrays/fa_0.85cs_0.15pbi₃ Perovskite

As an important part of sensors,photodetectors have been widely used in military and national economic fields,including weapons guidance,optical communications,electronic interference,industrial control,forest fire prevention,smoking alarm,light switching,etc.In particular,silicon-based photodetectors,which have the advantages of mature processing technology,stable performance,low manufacturing cost and large crust reserves,have attracted extensive research interest.However,due to the limitation of the bandgap of silicon,the performance of silicon-based photodetectors are unsatisfactory for near infrared light.In order to solve the problems,the heterojunction of perovskite materials and silicon nanowires was obtained to studied optoelectronic performance,analyzed detection mechanism and potential problems.The details are as follows:Silicon vertical nanowire array with good morphology was prepared by the metal assisted chemical etching method.And a one-step solution synthesis method was used to prepare the precursor solution of FA_0.85Cs_0.15PbI₃ perovskite.The heterojunction photodetector of silicon nanowire and FA_0.85Cs_0.15PbI₃ perovskite was obtained through the processes of spin coating,annealing and electrode deposition.Through testing of device characteristic,it was found that the device is sensitive to 850 nm light and have self-driven ability.What's more,the corresponding parameters like the response,detectivity,3 dB bandwidth,linear dynamic range,rise and fall time of the device were14.86 mA/W,4.1 x 10¹² Jones,3 MHz,81.8 dB and 60 ns/75 ns,respectively.Through the above work,it is proved that the heterojunction photodetector of the FA_0.85Cs_0.15PbI₃ perovskite and silicon nanowires can optimize the performance of the silicon-based photodetector in near infrared.In addition,through the construction of ultrathin heterojunction,the response speed of the device has been improved unprecedently,which have a great potential in silicon-base near infrared photodetectors.