SAN JOSE, Calif. -- The College of Nanoscale Science and Engineering (CNSE) of the University at Albany, N.Y. and Technic Inc. have announced an R&D partnership that is designed to enable critical improvements in manufacturing processes for solar cells.
CNSE and Technic's Advanced Technology Division, based in Plainview, N.Y., have begun collaborations on the $500,000 program to improve the efficiency of solar cells while lowering the costs of manufacturing. The collaboration is supported by a $200,000 grant provided by the New York State Energy Research and Development Authority.
The collaboration has already made progress in the development of alternative metallization solutions for solar cell manufacturing, through the deployment of electroless plating tools and chemical processes to replace the costly silver paste grid line process.
''Screen-printing is widely used today as the metallization technique for industrial solar cells. Due to the limitation of the process, screen-printed contacts have low aspect ratio and low line conductivity that lower the efficiency of the solar cells,'' according to a recent paper given by CNSE and Technic Inc. ''Photolithography and metal evaporation techniques are often used for high efficiency cells since they offer improved gridline quality, however the processes are time-consuming and expensive.''
The entities have developed another process. The solar cells were plated in Technic' so-called Benchtop LIP cell tool.
''To address this issue, we developed a two-layer metallization process that deposited copper (Cu) as current-carrying electrodes by light induced electroplating (LIP) technique on thin screen-printed silver (Ag) paste seed layers,'' according to the paper.
''A nickel (Ni) layer was also deposited by LIP as the barrier and Cu adhesion layer. A series of trials with various electrolyte compositions as well as different organic additives were investigated as part of this work,'' according to the paper.
''Preliminary cell performance study data have shown that front side resistance before plating was on average 0.122 ohms while after plating it was improved to 0.054 ohms potentially producing 100 percent more current and therefore more power output. In addition, electroplated deposits have better aspect ratios, so they can be deposited in a thinner line, resulting in less shading of the PV material and greater electricity production by the module,'' according to the paper.