The first electrode layer, pref. a transparent layer of metal-oxide, pref. ITO, is structured directly after its depsn.. The method used is pref. a lift-off technique using a TiO2-layer, local conversion of the electrode material e.g. by melting immediately followed by cooling of by spark-erosion. At the same time as the electrode pattern is made pref. a strip of electrically conducting material is deposited. In addition to this strip a parallel one of lift-off material, pref. deposited as a TiO2-paste, is formed. Then the semiconductor material, at least one layer, and the second electrode layer are deposited. Using e.g. ultrasonic agitation in a solvent the material above the TiO2-strip is removed, leaving separate strips of semiconductor with top-electrode. Using spark-erosion contact is made between the strip of conductive material deposited on the first electrode and the top electrode of the adjacent cell. Alternatively, if the conductive strips were not formed already, conductive paste is used to make the connection in the space between parallel strips.
USE/ADVANTAGE -The process represents an easier method with fewer disadvantages than current techniques to connect solar cells in series. Formation of the pattern in the first electrode layer before depsn. of any other material allows the best technique to be used. The use of lift-off techniques avoids etching or potentially damaging thermal techniques to separate the strips.
