Chemical Vapor Deposition Synthesis Of Single-/few-layer ?-In₂S₃ And Its Optical And Electronic Characterization

In recent years,two-dimensional materials with the discovery of graphene have begun to flourish.While chasing graphene,a large number of two-dimensional materials other than graphene have also been developed.Among them,metal sulfide is a very important component in the large family of semiconductor materials.?-In₂S₃nanomaterials are different from their bulk materials and have many novel properties.They are concerned by researchers.However,there are still many difficulties in controlling the synthesis of?-In₂S₃ nanomaterials.In this thesis,single-layer and few-layer?-In₂S₃ crystal films were prepared by chemical vapor deposition and characterized and analyzed.The fluorescence-enhanced bubbles formed under certain conditions were also analyzed.?1?Single-layer and few-layer?-In₂S₃ crystal films were prepared by chemical vapor deposition on single crystal graphite sheets,MoS₂ thin films and WS₂ thin films.The various factors affecting the morphology of deposited?-In₂S₃ were summarized.The optimized growth process of?-In₂S₃-WS₂ van der waals heterojunction was prepared and characterized.It was found that the interlayer coupling between the single-layer and the few-layer?-In₂S₃ and MoS₂ and WS₂ is weakly coupled.Subsequently,the optoelectronic properties of the?-In₂S₃-WS₂ van der waals heterojunction were studied:its switching ratio was about 10,the mobility was about 1.04×10^-44 cm²/Vs,and the incident optical power density was 25.48 W/cm².The photo response current is up to 1.59 nA,and the optical response rate is 6.2 mA/W when the incident optical power density is 0.06 W/cm².?2?In the process of preparing the heterojunction,a bubble with the appearance of the oscillating aura is produced,and the bubble is also generated by annealing the WS₂crystal.The design experiment explores the cause of the bubble.A series of investigations on this kind of bubble were carried out.It was found that the bubble shape conformed to the spherical crown model and optically conformed to the equal-thickness interference model.The photoluminescence and Raman spectra of WS₂ films after bubble formation were investigated.It is also confirmed that the optical appearance of the WS₂ film with oscillating aura after the formation of bubbles and the oscillation of the peak intensity in the photoluminescence spectrum and the Raman spectrum are caused by interference enhancement and interference cancellation of light.