Industrial inert drying system for high efficiency heterojunction solar cells

The heterojunction cell concept has become common in the field of solar cell research and development due to their high efficiencies and their simple low-cost production process. Due to the temperature sensitivity of the included intrinsic layer the curing process is limited to low temperatures. Because of their low-curing temperature, polymer pastes are an excellent low temperature metallization solution. As shown in previous works [2-3], an inert curing atmosphere can improve dramatically the paste and contact resistance of commercial available copper and silver based polymer pastes. Hence, this work focuses on the development of an industrial inert inline drying system to improve the low-temperature metallization process. In further experiments, the verification of the industrial inert low temperature curing process will be shown by cell efficiency of commercial polymer pastes on high efficiency heterojunction solar cells. In this work it is shown that each paste has to be cured at its own optimized curing conditions to achieve the best cell efficiencies. Therewith a cell efficiency of 19.96% could be reached with a commercial copper polymer paste.