ZnO Thin Film Preparation And ZnO/ZnSe/c-Si Solar Cell Simulation Study

Zinc oxide(ZnO)as a transition metal oxide(Transition Metal Oxides,TMOs)has excellent optical and electrical properties,how to apply it to the field of new energy has become one of the important research directions.The structure and properties of ZnO thin films are closely related to the preparation process.Selecting appropriate process parameters is the key to preparing high-quality thin film materials.Exploring the correlation between thin film properties and process parameters is the research basis for obtaining high-quality thin film materials.In the industrial application of thin films,the excellent photoelectric properties of ZnO thin film make it shines in the field of solar cells.It can not only be used as an electron transport layer but also as a transparent top electrode,which can effectively improve the photoelectric conversion efficiency of solar cells.This thesis has done two studies on ZnO thin film materials.The first is to use the radio frequency magnetron sputtering method,using a combination of pure Ar and ZnO ceramic target,and preparing 7 sets of ZnO thin film samples by changing the sputtering time and air pressure.Then use dual-beam electron microscope,X-ray energy spectrometer,ultraviolet-visible spectrophotometer and four-probe tester to characterize parameters such as surface morphology,element content,light transmittance and sheet resistance of the thin film samples.Study the effects of sputtering time and pressure on the microstructure and photoelectric properties of ZnO thin films;The second is to study a ZnO(n)/ZnSe(i)/c-Si(p)heterojunction solar cell using ZnO thin films,and use the heterojunction solar cell simulation software-AFORS-HET to study the effects of parameters such as film thickness,doping concentration,defect,top electrode material and ambient temperature on the performance of the solar cell.The conclusions are as follows:1.ZnO thin films preparation:when the sputtering time reaches 45 min or more,grain size increases and roughness is improved significantly of the thin films;The ZnO thin film with a sputtering pressure of 4.0 Pa has the steepest light absorption edge,the smallest sheet resistance,and the best film quality.Therefore,the sputtering time can be adjusted to more than 45 min under the sputtering pressure of 4.0 Pa in the production process.In this way,high-quality ZnO thin films with excellent microstructure and photoelectric properties can be obtained.And in practical applications,laser cutting technology can be used to adjust thin film thickness,so as to obtain thin film materials that meet various needs.2.ZnO/ZnSe/c-Si solar cell simulation:when the ambient temperature is 300 K,under the optimized parameters of 10 nm thickness and 1018 cm-3 doping concentration of ZnO emission layer,10 nm thickness of ZnSe intrinsic layer,1021cm-3 doping concentration of c-Si absorption layer,1017 cm-3 defect density in ZnO and c-Si layer,1025 cm-3 defect density in ZnSe/c-Si interface and the top electrode material is ZnO thin film,the photoelectric conversion efficiency can reach up to 30.37%.Compared with the ZnO(n)/Si(p)structure,it has a great improvement.The experimental results provide a certain theoretical basis and reference value for the setting of sputtering time and pressure parameters when preparing high-quality ZnO thin films by radio frequency magnetron sputtering and the application of ZnO thin film materials in high efficiency heterojunction silicon-based solar cells.