Study On Theoretical Calculation Of Optimum Doping Content In Luminescence Materials

Semiconductor luminescence materials and devices were developed as one of semiconductor technology in 1960.The luminescence devices made with the materials had developed quickly. But the pure semiconductor materials could not better because the luminescence efficiencies were lower. Doping is very important in order to improve the luminescence efficiency. By doping material properties will be better.When one of the materials became research highlight, many experiments would be made on doping and the preparation method. The different group did various experiments. Experiments results were not different. Too much doping content will destroy the materials properties. So optimum content is one of the highlight research jobs.Before authors only did experiments according to experiences and then gave some qualitative explanations. There were never quantitative calculations reported. In this paper, we analyze the doping experiments of several representational semiconductors and conclude the theoretical formula from different aspects. Optimum doping contents in various materials of semiconductor materials are calculated. The quantitative calculation values are in accordance with the experimental results.There are some creations in this paper. First, the relationship among the physical property, crystal structure, preparation method and doping content is established to be a parabola equation. The extreme value of this equation determines the optimum doping content. The expression of optimum doping content is proposed. Second, in luminescence materials hole or electron concentration will change with the doping content. So we expand the hole or electron concentration in Taylor expansion and calculat the optimum doping contents.For several semiconductor materials such as ZnS:Mn, Silicon doped Er and GaAs,GaP,GaN doped different materials, we calculat their optimum doping contents which arc close to some experimental results.The problem of optimum doping content must imply some rules undiscovered and the optimum doping content may be a very fundamental problem almost in all the fields of research work for material science.