Abstract: Based on the Finite-Difference Frequency-Domain(FDFD) method and the range of effective absorption wavelength, the thickness of buffer layer and the size of optical microcavity clear aperture of optical microcavity light-trapping structure in a-Si solar cell that the thickness of active layer is 300 nm are optimized by using light field distribution, light throughput and active layer absorption spectra, and the photocurrent density spectrum, the total current density and the output parameter are analyzed.The results show that the active layer has a maximum absorption efficiency when the thickness of the buffer layer is 2.6 μm and the clear aperture diameter Φ=D×0.8/8;The short-circuit current of the optimized cell is 25.9225 mA/cm2, which is better than that obtained by other light-trapping structures.

Key words: Based on the Finite-Difference Frequency-Domain(FDFD) method and the range of effective absorption wavelength, the thickness of buffer layer and the size of optical microcavity clear aperture of optical microcavity light-trapping structure in a-Si solar cell that the thickness of active layer is 300 nm are optimized by using light field distribution, light throughput and active layer absorption spectra, and the photocurrent density spectrum, the total current density and the output parameter are analyzed.The results show that the active layer has a maximum absorption efficiency when the thickness of the buffer layer is 2.6 μm and the clear aperture diameter Φ=D×0.8/8;The short-circuit current of the optimized cell is 25.9225 mA/cm2, which is better than that obtained by other light-trapping structures.