A First-principles Calculation Study Of The Electronic And Optical Properties Of Quaternary Alloy GaAsBin

Semiconductor has attracted people’s attention for its unique nature since it wasborn. As a representative of the first generation of semiconductor materials, silicon isthe most important component of the central processing unit(CPU). Nowadays, weare in an era of rapid development of information. So the importance of photovoltaicmaterials is self-evident. The second-generation semiconductor plays a key role in thefield of optical fiber communication, like GaAs and InSb. In order to expand theapplication region of these materials, some kind of defect atoms has been mixed withpure materials to exchange the natural property, which has been proved to be aneffective way. But the following question like heterogeneous compatible has becomethe stumbling block in the preparation of semiconductor.In this paper, we propose a Ⅲ-Ⅴ alloy GaAsBiN, as a potential candidate forthe long wave material. Through the deployment of two different sizes of impurityatom ratio, so that the semiconductor alloys lattice constants can match with the GaAssubstrate. It could be more effectively to regulate the electronic properties ofmaterials with the two kinds of impurity elements.Firstly, we briefly introduce the background of semiconductor materials,including the application of the first generation and the second generationsemiconductor, the experiments and theory progress of impurity, as well as variousproblems encountered. Then we show the superiority of our model.The second chapter, we introduce the basic concepts of density functional theory,as well as some disadvantages and solutions. The information of the simulationsoftware package we used is also in this chapterThe third chapter, we investigate the structure properties and electronicproperties of the binary alloy--GaAs, GaN, GaBi. According to the Vegard law, wefound an appropriate doping ratio of Bi and N which could make the quaternary alloylattice-matched with GaAs. Then, we show result research about the impurity states inthe GaAsBi alloy. The fourth chapter, by using the first-principles combined with hybrid functionalcalculations, electronic and optical properties of GaAs alloyed by isovalent impuritiesBi and N are studied. We research the location of the impurity states induced by theBi and N atoms, and give some explanation. Then we show a picture about thefunctional relation of the bandgap and impurity ratio, which gives a direct expressionabout the accuracy of HSE06. We also find the distortion of the lattice have a greatinfluence on the bandgap. The absorption of the quaternary alloy shows an obviousredshift compared with GaAs, which demonstrated our initial judgments on this alloymodel.At last, there is a summarize of this paper. With the development ofsemiconductor fabrication technology, the alloy model we proposed would have agood application prospect in the fields of infrared photoelectric materials.