Investigation on plated Ni/Cu contact for mono-crystalline silicon solar cells

Silicon solar cells are required to be processed with low cost and high efficiency. Ag paste, which is frequently used for the front contact of commercial screen-printed solar cells, has high contact resistance and high cost. Therefore, it is necessary to develop an inexpensive metallization technique with improved cell performance. As an alternative, plated Ni/Cu contact was used to fabricate low cost and high efficiency solar cells in this paper. Ni/Cu metals have low cost, low contact resistance and high conductivity. Ni was formed for low contact resistance and barrier to plated Cu, which was the main contact for low cost and high conductivity. In particular, a plated Ni layer is a very crucial factor that determines performance of the contact for plated Ni/Cu solar cells. A plated Ni layer has a decisive effect on contact resistance, series resistance and fill factor. In this paper, Ni electroless plating conditions (deposition time and pH) were varied to form a well plated Ni layer. For an optimized Ni electroless plating condition (5 min of deposition time and 8.5 of pH), the efficiency of plated Ni/Cu contact solar cells recorded 18.68%.