Large area CdS/CdTe solar cells

A deposition technique, called the writing method, is developed and applied to the fabrication of CdS window layer in CdS/CdTe solar cells produced by the screen-printing and sintering method. Obtained CdS film is quite smooth with very few pinholes. It is proved that this technique possesses high patterning precision. Furthermore, heat treatment of glass/CdS/CdTe substrates in H₂+N₂ atmosphere decreases the sheet resistance of CdS film by about one order of magnitude. High-precision patterning ability and low sheet resistivity of CdS window realize high active/total area ratio of more than 0.8. As a result of these improvements, the conversion efficiency of 8.1% in 1200 cm² (10.1% active area efficiency) is obtained