| Transparent conductive oxide?TCO?films are widely used in all walks of life because of their excellent photoelectric performance,especially in the aspect of thin film solar cells.With the rapid development of thin-film solar cells,the actual demand for thin films with high light transmission and excellent electrical conductivity has increased rapidly,and many researchers have focused their attention on the preparation of new films with excellent photoelectric properties.Most of the existing methods for fabricating such films are relatively complicated or lack systematic analysis and research on film properties.However,there are few reports on the fabrication of the anti-reflection layers/structures on the surfaces of TCO films and their photoelectric properties.Based on this,this paper proposes to fabricate the anti-reflection layers/structures on the surfaces of the film by laser processing fluorine-doped tin dioxide?FTO?and aluminum-doped zinc oxide?AZO?films and combining with the coating process.The fabrication method,related mechanisms and the influence of the thickness of the deposited film and the laser parameters on the photoelectric performance of the thin film has obtained some meaningful research results.1.Using a 532 nm nanosecond pulse laser to remove the surface of grid FTO film deposited with the AZO driving layer and the Ag film layer,under the condition of fixed laser parameters,the thickness of the AZO driving layer and Ag layer on the film was systematically studied.The influence of sample surface morphology,crystal structure and photoelectric performance,and the mechanism of AZO driving layer and the anti-reflection effect of Ag nanoparticles?Ag NPs?were discussed and analyzed.The experimental results showed that different AZO driving layer and Ag layer thickness will form Ag NPs with different sizes and different distribution rules in the film surface grooves.These Ag NPs could bring different anti-reflection effects and comprehensive photoelectric properties to the film samples.When the thickness of the AZO driving layer was 20 nm and the thickness of the Ag layer was 150nm,the average transmittance of the obtained film sample was 79.95%,the average reflectance was 8.04%,the sheet resistance was 7.11?/sq,and the highest figure of merit was 1.50×10–2?–1,better than the untreated FTO film and the film samples without the introduction of AZO driving layer.2.Using a 532 nm nanosecond pulse laser to etch the AZO film to fabricate the anti-reflection grating structures on the surface of the AZO film.The effects of defocusing amount,scanning speed,line spacing and laser fluence on the film surface morphology,crystal structure and photoelectric performance were systematically studied.The anti-reflection mechanism of the etched grating structure was also discussed.It was found that neither too narrow or too wide grating line spacing?corresponding to the grating period?nor too low or too high laser fluence?corresponding to the grating height?could make the film obtain the best anti-reflection effect.Under different laser parameters,the competitive effects of the additional laser annealing and laser etching to partially remove the AZO layer would also cause differences in the photoelectric performance of the film.In the experiments of this chapter,when the defocusing amount was 0.2 mm after defocusing,the scanning speed was 5 mm/s,the line spacing was 40?m,and the laser fluence was 0.6 J/cm2,the fabricated film grating structure had the best anti-reflection effect and can simultaneously obtained the optimal laser annealing effect.The average transmittance,average reflectance,sheet resistance and the figure of merit of the film samples obtained by laser etching were 87.77%,9.09%,9.38?/sq and 2.89×10–2?–1,which were better than the untreated AZO film.3.A 532 nm nanosecond pulse laser was used to perform double-oriented laser etching on the AZO film.On the basis of the experiment in the previous chapter,the laser was etched under the same parameters perpendicular to the direction of the single-oriented grating.The differences in surface morphology,crystal structure,and photoelectric performance between single-oriented and double-oriented gratings were compared and studied.It was found that the removal of more AZO layers on the surface of the double-oriented grating caused a decrease in the conductivity of the film sample,while the removal of more AZO layers and the secondary optimization of the additional laser annealing effect improved the optical performance of the film.Under the competitive effect between this two,it was found that the double-oriented grating is better than the single-oriented grating as a whole by comparing the comprehensive photoelectric performance.In this experiment,the average light transmittance,average reflectance,sheet resistance and the figure of merit of double-oriented grating film samples were 88.23%,8.73%,9.57?/sq and 2.99×10–2?–1,which was better than the untreated AZO film and was also slightly better than the single-oriented grating. |
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