Design Of High Efficiency Thin Film Gallium Arsenide Solar Cells Based On Subwavelength Structure

Solar energy as kind of clean and renewable energy will be a promising solution to the current environment pollution and energy crisis.As a means of harvesting solar energy,photovoltaic devices,which can directly convert sunlight into electrical energy,are widely studied all over the world.It is necessary to improve the efficiency and cost of solar cells in order to solve the global energy shortage problem.Because of The characteristic size of the subwavelength structure was smaller than the wavelength,and its reflectance,transmittance,polarization characteristics,and spectral characteristics all show distinct characteristics from those of the conventional diffractive optical element,subwavelength structure is a popular solution in the field of light-trapping.In this paper,Comsol Multiphysics,which was based on the finite element method,was simulate to several different light-trapping the subwavelength structures,including periodic arrangement silicon nitride nanocone array,randomly arranged silicon nitride nanocone array,anodic alumina film,silver nanohemisphere arrays and their combined structures.The relevant mechanisms were explained accordingly,which laid the foundation for the future preparation and application of nanostructures.Firstly,silicon nitride nanocone arrays was designed and constructed on the substrate of gallium arsenide by using Comsol Multiphysics simulation software.The reflection and absorption were calculated and compared with the silicon nitride nanorods of the same thickness.Secondly,the structural parameters of the silicon nitride nanocone array cell were optimized.After the periodic structural parameters were determined,on this basis,the effect of varying the randomness of the diameter,height,and position of the silicon nitride nanocone array on the overall performance of the cell was investigated within a certain range.Finally,a hybrid structure cell with a more complex structure was designed.The cell front layer structure was a double-layer antireflective coating and the back layer was silver nanoparticles.By comparing the electric field distribution diagrams of four different typesof cell,it was concluded that the performance of the hybrid cell was optimized.Then,the structural parameters of the hybrid structure cell were further optimized,and the optimal cell structural parameter values were obtained.