Review of Ni-Cu Based Front Side Metallization for c-Si Solar Cells. (21st November 2013)

• Record Type: Journal Article
• Authors: Raval, Mehul C.; Solanki, Chetan S.
• Other Names: Reehal Haricharan S. Academic Editor.
• Is Part Of: Journal of solar energy. Volume 2013(2013)
• Publication Date: 2013-11-21
• Subjects: Solar energy -- Periodicals; 621.4705
• DOI: 10.1155/2013/183812
• Languages: English
• ISSNs: 2356-7635

Abstract

Abstract : Given the high percentage of metal cost in cell processing and concerns due to increasing Ag prices, alternative metallization schemes are being considered. Ni-Cu based front side metallization offers potential advantages of finer grid lines, lower series resistance, and reduced costs. A brief overview of various front side patterning techniques is presented. Subsequently, working principle of various plating techniques is discussed. For electroless plated Ni seed layer, fill factor values nearing 80% and efficiencies close to 17.5% have been demonstrated, while for Light Induced Plating deposited layers, an efficiency of 19.2% has been reported. Various methods for qualifying adhesion and long term stability of metal stack are discussed. Adhesion strengths in the range of 1–2.7 N/mm have been obtained for Ni-Cu contacts tabbed with conventional soldering process. Given the significance of metallization properties, different methods for characterization are outlined. The problem of background plating for Ni-Cu based metallization along with the various methods for characterization is summarized. An economic evaluation of front side metallization indicates process cost saving of more than 50% with Ni-Cu-Sn based layers. Recent successful commercialization and demonstration of Ni-Cu based metallization on industrial scale indicate a potential major role of Ni-Cu based contacts in near future.