Abstract
We demonstrate the performance improvement of p-type single-crystalline silicon (sc-Si) solar cells resulting from front surface passivation by a thin amorphous silicon (a-Si) film deposited prior to phosphorus diffusion. The conversion efficiency was improved for the sample with an a-Si film of ∼5 nmthickness deposited on the front surface prior to high-temperature phosphorus diffusion,with respect to the samples with an a-Si film deposited on the front surface after phosphorus diffusion. The improvement inconversion efficiency is 0.4% absolute with respect to a-Si film passivated cells, that is, the cells with an a-Si film deposited onthe front surface after phosphorus diffusion. The new technique provided a 0.5% improvement in conversion efficiency comparedto the cells without a-Si passivation. Such performance improvements result from reduced surface recombination as well as loweredcontact resistance, the latter of which induces a high fill factor of the solar cell. Copyright © 2014 Ching-Tao Li et al.