CdS solar cells with electrochemically formed Cu2S Improvement of the current collect

CdS-Cu2S solar cells are made by depositing Cu2S on CdS by cathodic reduction from a solution containing the Cu(2+) species. A gold grid is electroplated onto the Cu2S formed before CdS etching to ensure good contact and collecting conditions. The shape of the grid is delimited using a photoresist technique. To protect the grid against the subsequent acidic etching process and a frequently observed copper deposit during the formation of Cu2S, a passivation method involving anodic polymerisation is described. The formation of Cu2S, as well as the subsequent copper enrichment are therefore easily performed, leading to cells with efficiencies of up to 8 percent.