Preparation Of Antimony Based Semiconductor Thin Films And Solar Cells By VTD Method

With the rapid development of society,people are facing two major problems:environmental pollution and energy shortage.Therefore,the demand for sustainable,renewable and low-cost energy has always been the focus of countries.New energy sources such as wind energy,hydropower and solar energy can effectively deal with these problems.Among them,solar energy is favored by people as a green and clean energy.Solar cell is an effective means to obtain solar energy.For solar cell,it generally takes high efficiency,low cost and long-term stability as the development index,in which high efficiency is the premise of development.At present,crystalline silicon solar cells occupy a dominant position in the photovoltaic field because of their high efficiency and good stability.At present,the research of new solar cells mainly focuses on three aspects:flexibility,low cost and low toxicity.Antimony based compounds have become one of the most popular solar cell materials because of their high abundance and good photoelectric properties.There are many factors that affect the efficiency of antimony based compound films and their solar cells,such as the preparation process of VTD method,the selection of solar cell buffer layer,etc.This paper will study the above related factors,and test them by XRD,Raman,SEM,EDS,NI-UV reflection spectrum,photocurrent response and I-V.This paper mainly consists of the following aspects.1.Sb₂Se₃thin films were grown on different substrates（SnO₂,ZnO,TiO₂,CdS）by VTD method.It was found that different substrates could induce the growth of grains in different orientations during the growth of the thin films.When the substrate was Cd S thin film,the photoelectric conversion efficiency of Sb₂Se₃thin film solar cell was the highest of1.87%.2.Sb₂Se₃thin films were prepared by VTD method at different growth angles（30°,45°,60°,90°）and characterized.The results show that different growth angles have obvious effects on the structure and optical properties of the films.With the increase of growth angle,the morphology of the films changes from rod growth to sheet growth.When the growth angle is 60°,the samples have the lowest reflectivity in the range of wavelength less than 1100 nm,The average photoelectric conversion efficiency of FTO/Cd S/Sb₂Se₃/C device prepared at this angle is 2.42%.3.Sb₂（S,Se）₃thin films with adjustable band gap were prepared by evaporation of Sb₂Se₃powder and Sb₂S₃powder together.By changing the temperature of the temperature zone in the VTD system and controlling the evaporation source temperature（440℃,460℃,480℃,500℃）,the effect of evaporation source temperature on Sb₂（S,Se）₃thin film and its solar cell is studied.4.Sb₂（S,Se）₃thin films were prepared by VTD method under different mass ratios of antimony selenide and antimony sulfide（0.1,0.25,0.5,0.75,1,1.25）,and analyzed by various characterization and testing methods.By changing S/Se,the band gap width of Sb₂（S,Se）₃thin film was adjusted to further improve the photoelectric conversion efficiency of the thin film solar cell.