Inkjet and laser hybrid processing for series interconnection of thin film photovoltaics

Abstract

Inkjet deposition can be a complementary technology to laser ablation to enable new processes. One such process is the One step interconnect for thin film photovoltaics, which is an improved method for series interconnection. The standard series interconnection process consists of three laser scribes between the deposition of the three key cell layers; transparent front contact, absorber layer and the metallic back contact. The one step interconnect allows the series interconnection to occur after the deposition of all layers significantly simplifying the manufacturing process. This is achieved by inkjet printing of conductive and insulative materials concurrently with depth selective laser scribes. The one step interconnect process has been shown to make effective interconnects on cadmium telluride photovoltaics with fill factors >60%. The benefits are many and include the reduction of capital equipment costs, reduced panel wastage and potentially improved material performance. The process is fully scalable and production ready.