INFLUENCE OF THE TiO 2 ANTIREFLECTION FILM THICKNESS IN THE ELECTRICAL PARAMETERS OF N-TYPE SOLAR CELLS
DOI:
https://doi.org/10.59627/cbens.2012.1990Keywords:
n-Type Si Solar Cells, Antireflection Film, Firing TemperatureAbstract
The reduction of reflection on the silicon solar cell surface is obtained by the deposition of thin films. The antireflection film (AR) of TiO 2 can be suitable for solar cells with boron doped emitters. However, the film characteristics are modified during the firing process of metal pastes and therefore the AR film variation influences the device efficiency. The aim of this paper is to analyse the variation of TiO2 antireflection film and the influence on the electrical characteristics of solar cells with boron doped emitter. To fabricate the solar cells, TiO 2 films of different thicknesses were deposited and the temperature of metal paste firing was varied in order to find the best temperature for each film thickness. Changes in the thickness, reflectance and wavelength related to the minimum reflectance were observed after firing process. For film thicknesses from 62 nm to 103 nm, the average reflectance after firing was of 3 % to 4 %. Best average cell efficiency was of 13.6 %, obtained with solar cells with 97 nm thick TiO 2 film and an average reflectance of 3.3%. Fill factor was not affected by the TiO 2 thickness, but the open circuit voltage and the short-circuit current density shown a slight enhancement with the thickness until 103 nm film.
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