Date: 28 July 2010
Called Metal Wrap Through (MWT), the proprietary technology has a number of advantages over conventional solar cell designs and is considered an important innovation in reducing manufacturing cost per peak Watt.
Ferro’s screen printable MWT metallization paste exhibits minimal shrinkage on firing, providing uniform cell-to-cell performance. The paste has excellent electrical conductivity, improving cell efficiency to as high as 17.6% on 160-μm thick polycrystalline silicon wafers. Independent labs have evaluated MWT paste and confirmed this high level of efficiency. Efficiency at the cell level is typically 0.2 to 0.5% higher than that for conventional cell designs when using the same wafer quality. Another benefit is that the MWT paste is applied in the same printing step as the rear side contacts and, therefore, does not add printing steps to the cell process.
Ferro’s screen printable metallization paste is being used in a special type of MWT cell called Sunweb®, which is based on the MWT concept of The Energy Center of The Netherlands and is being commercialized by Solland Solar. The Sunweb cell provides a number of important benefits over conventional solar cell designs. In the near future, further improvements are expected for Sunweb type of MWT cells as a result of ongoing efforts between solar cell and module manufacturers to fully optimize the module technology.