Fabrication Of Platinum Selenide Material And Application In Photodetector

Graphene was found in 2004,which confirmed that two-dimensional materials can exist stably at room temperature,and set off a research upsurge of two-dimensional materials.With the passage of time,many two-dimensional materials have been found successively,such as black phosphorus（b-p）、hexagonal boron nitride（BN）、transition metal sulfur compounds（TMDCs:MoS₂,PbS₂,MoSe₂,etc.）and Olefins,etc.As a new transition metal chalcogenide,platinum selenide（PtSe₂）has the common characteristics of two-dimensional materials,such as adjustable band gap and high carrier mobility.By adjusting its band gap,the measurement band of the detector can be widened to realize photoelectric detection from visible band to mid infrared band;High carrier mobility can make the photogenerated electron hole pair rapidly compound and realize fast Device response.The discovery of platinum selenide provides a new possibility for the preparation of photodetectors with low cost,wide band and rapid response at room temperature.In this paper,high-efficiency platinum selenide/silicon heterojunction photodetectors are prepared by directly growing platinum selenide on the substrate.Firstly,the growth conditions and characterization of platinum selenide are studied,and then the optical response of platinum selenide/silicon heterojunction photodetectors is explored:1.Platinum selenide films was prepared and charactered.First,the high-quality Pt filmobtained by electron beam evaporation equipment is used,and then the film is selenized by chemical vapor deposition.The environment of selenization was controlled by adjusting temperature,argon flux and selenium source quality,so as to obtain the high-quality Pt films.Then,the platinum selenide films were characterized and analyzed by scanning electron microscopy（SEM）、atomic force microscopy（AFM）and Raman spectroscopy（Raman）and other equipment.2.The photoelectric properties of PtSe₂/Si heterojunction photodetectors were researched.In order to construct a high-quality interface photoelectric detector,we directly grow platinum selenide on the etched silicon/silica window substrate,and test the photoelectric response of the device in the visible to mid infrared band.The fast response time of 4/3ms is obtained in the visible light band.The specific detection rate,response and open light ratio are 4.39×10¹² Jones,202 mAW^-1 and 1.31×10⁵,respectively.It also has good photoelectric response in the near infrared and mid infrared band.3.The effect of pyramidal microstructure on PtSe₂/Si Heterojunction photodetectors was investigated.The pyramidal structure is etched on the surface of silicon substrate by etching technology,and the optical absorption of the device is increased by pyramidal structure,so as to improve the performance of the device.