Abstract: The effects of contact electrode size on the photo-voltaic characteristics of polycrystalline-Si p–i–n solar cells have been studied, with respect to a unit-cell pitch size of 1 μ m width. For the non-transparent Al contact electrode with a contact width of 0.05–0.2 μm, the short-circuit current is obviously reduced with increasing contact width, due to a larger area of optical reflection by the electrode. On the other hand, even when using a transparent ITO (indium-tin-oxide) electrode, a larger width of contact electrode may also cause a smaller short-circuit current, due to a larger area of optical absorption by the electrode. However, for this ITO electrode, the contact electrode of 0.05 μm width causes a smaller short-circuit current than that of 0.1 μm width, primarily ascribed to a smaller area for collecting carrier and a larger contact resistance. As a result, while using the ITO contact electrode to enhance the conversion efficiency of the solar cell, a proper width of contact electrode should be employed to optimize the photo-voltaic characteristics.

Key words: polycrystalline-Si solar cell