Addressing adhesion and reliability concerns of copper-plated c-Si solar cells and modules

Copper-plated contacts for front side crystalline silicon solar cells are a topic of considerable interest, with many recent publications presenting a variety of successful methods and impressive cell results. Several of the more obvious challenges yet to be proven relate to the durability and reliability of plated contacts, especially the adhesion of plated metal to solar cells and the long-term stability of the metals that could potentially result in gradual power degradation. In this work, we have fabricated copper plated cells using several different front side patterning methods. For a resist-based process, we have optimized plated cell processing to achieve adhesion comparable to screenprinted silver paste contacts. For laser-based patterning methods, greater understanding of the metal-silicon interface and microstructure effecting adhesion is still needed.