The Effect Of Dangling Bands On Photoelectric Properties Of SiC Nanowires

Silicon carbide(sic)is a kind of wide band gap semiconductor material with broad application prospects,its excellent mechanical,thermal,optical and electrical properties have attracted more and more attention,such as its high hardness and good wear resistance,silicon carbide was first used as an abrasive in engineering.SiC nanowires,which are one-dimensional nanomaterials,are studied in this paper,so there are two dimension sizes between 1-100 nm.Compared with other nanomaterials,SiC nanowires have two quantum limited directions.Therefore,nanowires have excellent thermal stability,mechanical properties,electron and photon transport properties,optical properties,photoconductivity and field emission effects,there are also surface effects,quantum size effects and small size effects.In this paper,we focus on the surface modification of silicon carbide nanowires and their doped silicon carbide nanowires structure stability,electronic structure and optical properties.The main contents are as follows.Firstly,the development history of nanomaterials,semiconductors and silicon carbide is briefly described,and the corresponding basic theory and the simulation software involved are described in detail.Then,we use Castep module to construct and optimize the structure of silicon carbide nanowires before and after hydrogen atom passivation.At the same time,we study the different morphologies and size of nanowires in detail.The effect of surface dangling bonds on nanowires are mainly investigated by energy band,density of states,optical properties and so on.Finally,the doping of nitrogen and phosphorus atoms is carried out on the basis of above.It is found that the impurity level caused by doping changes with the presence or absence of dangling bonds,furthermore,the reasons are analyzed from the electrical and optical properties.