Preparation Of Microlens Array And Grating Fold Structure And Its Application In Solar Cells

Silicon solar cells have the advantages of non-toxic,reliable,low price,and stable performance,and have occupied more than 90% of the modern photovoltaic market,and researchers have been conducting research to improve their performance.Microlens arrays have attracted the attention of scientists because of their good optical characteristics such as small size,variable refractive index,arraying,etc.,and have a trapping effect on the incident light entering the surface of solar cells,which can effectively improve the photoelectric conversion ability of solar cells.In this paper,photoresist film microlens array molds with different structures and sizes were prepared on silicon substrates by photolithography combined with the thermal reflux process,and the microlens arrays were successfully prepared on the surface of solar cells by ultraviolet nanoimprinting technology.The periodically modulated microlens nanograting fold structure was prepared by plasma treatment and applied to the surface of solar cells,and the influence of microstructure on the photoelectric conversion performance of solar cells was studied.The specific work content is as follows:(1)Microlens array templates of different sizes were prepared on silicon substrates by photolithography combined with a thermal reflux process,and the structures were round,hexagonal,and square.The structure was copied to the glass substrate by ultraviolet nanoimprinting technology,and the surface morphology of the photoresist film microlens array was tested by scanning electron microscopy,and the test results showed that the prepared microlens array structure was uniform in size,tightly arranged,and smooth in surface.The optical focusing and imaging performance of the photoresist thin film microlens array was tested by an optical microscope,and the results showed that the prepared photoresist thin film microlens array had good optical focusing and imaging performance.(2)The photoresist film microlens array was applied to the surface of the solar cell,and the surface water droplet contact angle of the solar cell was tested,and the results showed that the photoresist film microlens array solar cell had good surface hydrophobicity,and the microlens array structure could improve the surface self-cleaning ability of the solar cell.The photoelectric conversion performance of photoresist thin film microlens array solar cells was tested by a simulated solar detection station,and the photoelectric conversion efficiency of square microlens array solar cells with a lens side length of 15μm was increased by about 14.40%.(3)The grating fold structure was prepared on the surface of PDMS film by oxygen plasma treatment technology combined with stretching technology,and the influence of plasma treatment power and processing time on the cycle and depth of the grating fold was studied.The surface contour of the grating fold structure was tested using scanning electron microscopy and atomic force microscopy,and the test results showed that the prepared grating fold structure had a smooth surface and uniform structure,and the period and depth of the grating fold increased with the increase of plasma processing power and time.Furthermore,the grating fold structure was prepared on the surface of the PDMS microlens array and applied to solar cells,and the grating fold on the surface of the PDMS microlens array was observed by scanning electron microscopy,and the grating fold on the surface of the PDMS microlens array was clearly visible,uniform and complete in structure.