CdS thin films of high quality with good reproducibility can be prepared on large-area substrates from aqueous baths, icontaining triethanolamine complex of Cd2+ ions and thiourea. Depending on the deposition para-meters, a combination of optoelectronic cha-racteristics are obtainable: optical transmi-ssioii, 10.7 q80%; photocnductivity, up to 3 ohm-1 cm-1 (at 300 W/m2 sim. solar); photo; conductivity to dark conductivity ratio, 10° to 109 and phstocurrent decay time , a few seconds to -103 s. Absorber layers (p-type) of lower band gap, of the CuxS or CuInS2 type, with low sheet resistivities have been subsequently chemically deposited on these CdS films. This suggests the possibility of developing 'all-chemically deposited' thin film solar cells.