15 September 2010
Natcore Technology Inc. researchers have discovered a method to “passivate” the surface of the solar cell on which a silica film has been grown using Natcore's liquid phase deposition (LPD) process.
Passivation is the process of filling the dangling atomic bonds at the surface of the solar cell, as well as reducing the numbers of defects that always exist in the upper region of the cell body. It is critical to enabling production of long-term, high-performance, silicon solar cells.
In Natcore's refined LPD process, this necessary passivation is achieved using the same production steps normally applied to the solar cell to create its top and bottom metal contacts with no additional heating cycles required. The synergistic nature of Natcore's technology with existing cell fabrication steps will simplify the standard silicon solar cell manufacturing process.
Recent developments in silicon solar cell manufacturing research and development have shown that significant gains in cell performance can be achieved with ever-thinner silicon wafers by passivating the rear surface of the cell with a layer of silica underneath the full-coverage aluminum back contact. This step has not yet been included in actual manufacturing because it presently requires the deposition of the silica film by thermal vacuum processes that are too cumbersome and costly to implement.
In contrast, Natcore's newly discovered passivation process using its LPD technology could enable manufacturers to incorporate this vital step in their manufacturing lines in a simple and cost-effective manner.