Scanning light spot scan and electron-beam-induced current studies of CdS/CuxS solar cells formed on rough and smooth single-crystal CdS substrates

Abstract CdS/Cu x S solar cells prepared on a single-crystal CdS substrate, half of which has been roughened by an HCl etch, are examined using scanning light spot and electron-beam-induced current scans. It is shown that the roughened side of the cell has a greater response than the smooth side and that the response of the rough side is improved by an anneal whereas there is no improvement on the smooth side. We suggest that this is because the structure of the Cu x S on the rough surface side is different from that on the smooth surface side and is improved after an anneal. We also show that the response of a cell fabricated on a CdS bicrystal is lower in the crystallite with more internal stress and that the response on the smooth surface side of the cell decays more slowly.