The Study On The Influence Of Different Layers Of HIT Solar Cell On The Device

Energy is a necessary condition for human survival and development.For thousands of years,human society has developed rapidly due to the use of traditional energy.Especially the emergence of the first industrial revolution and the second industrial revolution,the human society has undergone earth-shaking changes,but at the same time because of the use of coal,oil and other traditional fossil energy,the earth’s ecological environment has been greatly damaged,species even facing the threat of survival.Therefore,the new energy technology represented by solar cell has attracted great attention of people,and the key factor restricting the development of solar cell is its photoelectric conversion efficiency.As the most potential solar cell,HIT solar cell has higher efficiency,so it is necessary to increase the investment and research on HIT solar cell.In this project,employing the AFORS-HET the performance of the heterojunction solar cell is calculated by numerical simulation.Through setting different parameter of each function film layer,performance change of three kinds of HIT solar cell with different structure is investigated。The concrete research content and the result are as follows:（1）The first structure cell can be optimized when the thickness of its emission layer,substrate and backfield layer is 4 nm,300 m and 4 nm,respectively.The best performance is achieved when the thickness of the emitting layer,intrinsic layer,substrate and backfield layer of the n-type cell with second structure is 4 nm,4 nm,150 m and 4 nm,respectively,while the best performance is achieved when the thickness of the emitting layer,intrinsic layer,substrate and backfield layer of the p-type cell is 4 nm,4 nm,200μm and 4 nm,respectively.The best performance is achieved when the thickness of emission layer,front intrinsic layer,substrate back intrinsic layer and back layer of n-type cell with third structure is 4 nm,4 nm,150 m,4 nm and 4 nm respectively.while the best performance is achieved when the thickness of emission layer,front intrinsic layer,substrate,back intrinsic layer and back layer of p-type cell is 4 nm,4 nm,200μm,4 nm and 4 nm respectively.（2）With the increase of substrate doping concentration,the conversion efficiency of the three kinds of cell is improved.When the doping concentration is 1*10¹77 cm^-3,the conversion efficiency tends to be flat.However,when the doping concentration of the emission layer and the backfield layer is greater than 1*10¹⁹ cm^-3,the performance of the cell remains basically unchanged.With the increase of defect state density（Dit）,the performance of the cell decreases.For p-type HIT cell,with the increase of the work function,the cell performance decreases.For n-type substrate HIT cell,with the increase of the work function,the cell performance increases.Considering all kinds of parameters,for the traditional no intrinsic layer and single intrinsic,the substrate defect density of substrates has the greatest effect in the cell efficiency.For cell structure with double intrinsic layer,double layer passivation effect is remarkable,the impact is limited.On the contrary,the substrate doping concentration has the greatest effect on the cell efficiency.（3）Among the three cell structures,n-HIT cell with dual intrinsic layers has the highest conversion efficiency（27.54%）,which is the most ideal cell structure theoretically.While other conversion efficiency is relatively low.Considering absorption losses of the different kinds of TCO thin films in a cell,the spectral response of the ZnO thin film is higher and the ZnO thin film is more transparent than ITO thin film,so chooseing ZnO as window layer,spectral response effect within corresponding wavelength range is significantly increased,to make corresponding HIT solar cell short-circuit is bigger,the cell conversion efficiency is higher.