Fabrication of the a-Si Solar Cells with the Light Trapping Structure by the Al₂O₃ Fine Particles

Abstract

  The development of the high-efficiency a-Si:H solar cells has been achieved, fabricating the light trapping structures by the use of Al₂O₃ fine particles. As a result of the inserting the Al₂O₃ fine particles between the a-Si:H and the Ag back electrodes, the remarkable increase in the short circuit photocurrent density J_sc was achieved while no significant change was observed both in the open circuit voltage Voc and the fill factor. Observation of quantum efficiency spectra for the solar cells with Al₂O₃ particles indicates that this increase in the photocurrent density is due to the improvement of the sensitivity in the long wavelength regime (570-750 nm). It is concluded that Al₂O₃ particles cause random reflection of incident light at the interface, leading to an increase in the optical path.