Influence Of Optical Modulation Structure On The Performance Of Solar Cells

The thesis introduces the research and development of solar cell industry. And analyze in detail about the structure and mechanisms of silicon p-i-n based solar cells. In order to increase absorption of solar photons and improve energy conversion efficiency, the structure parameters of the cells are optimized. In addition, optical modulation structures, such as DBR mirror and grating, are designed and combined with the p-i-n structure to improve the performance of the solar cell.The p-i-n structure solar cell layers to be optimized with MEDICI software. Simulations show that ITO transmittance is largest when anti reflection coating thickness is 0.06μm, The concentration of p-doped region is 1019 per cubic centimeter and the thickness of p-doped region is about 0.01μm that the characteristics of solar cell is the best. The efficiency of thin-film Si solar cells critically depends on optical absorption since it has low absorption coefficients in the red and near-infrared wavelength ranges. The distributed Bragg reflector based photon band theories and software simulations. The light can be scattered into solar cells by photon crystals since this designed DBR exhibits a complete photon band for the light from about 650 nm to 1000 nm. In this paper the photon crystal was simulated with software MEDICI, we further investigate the influence of DBR on solar cells. Simulations show that the characteristics of solar cell has been significantly improved, the fill factor from 0.842 to 0.852, while the conversion efficiency from 18.9% to 20.52%.In this paper we introduce modulated photon crystals, which in solar cell applications for extending the interval of high reflection coefficient over a much broader wavelength region than obtained using a regular photon crystal. The structure comprises two photon crystals parts, each consisting of layers different thicknesses. The simulations show that the modulated photon crystal has a high reflection coefficient over a much broader wavelength, Obtain a wide reflection spectrum 550 nm ~ 1400 nm wavelength band. The conversion efficiency increased to 21.02%. At the same time, periodic grating has diffraction effects, which making the optical path length can be significantly enhanced. This article uses FDTD Solution simulation the property of periodic grating. Studying light intensity(or electric field) after light through the periodic grating. It shows there were clear diffraction effect when add the optical grating.