Kaneka develops high-efficiency heterojunction silicon solar cell featuring copper electroplating

KANEKA CORPORATION
November 28, 2011
Kaneka (Osaka, Japan; President: Mr. Kimikazu Sugawara) has successfully developed a high-efficiency silver-free heterojunction silicon solar cell in collaboration with Belgium-based imec (President & CEO: Luc Van den hove).

The collector electrodes of conventional heterojunction solar cells are created via silver screen printing. This is a costly process involving expensive silver and difficulties of lowering the resistance or narrowing the electrodes. The silver-free method uses copper electroplating in place of silver screen printing to successfully reduce resistance, enable electrode narrowing and achieve a substantial improvement in production costs. This represents the first ever use of copper electroplating to create collector electrodes on heterojunction silicon solar cells. Copper electroplating is an economical and industrially proven process that addresses the deficiencies of silver screen printing while at the same time boosting conversion efficiency and substantially reducing production costs.

The new method involves the application of copper electroplating technology to Kaneka’s existing heterojunction solar cell production processes. Tests conducted in imec’s facilities demonstrated that six-inch square solar cells with copper electroplated collector electrodes on the transparent conductive oxide can boost conversion efficiency to 21% or more.

The new method was developed by research teams at Kaneka and Kaneka Belgium (Photovoltaics European Laboratory located in the facilities of imec in Leuven) having the cooperation of imec researchers. The silver-free process is an important step forward in the quest for a more efficient heterojunction silicon solar cell that will add further impetus to research and development into industrial applications.

The research findings will be announced at the 21st International Photovoltaic Science and Engineering Conference (PVSEC-21) which is held in Fukuoka City on November 28 – December 2, 2011, in the form of a joint presentation by Kaneka and imec entitled “High Efficiency Silver-Free Heterojunction Silicon Solar Cell.”

Outline of imec
Company name: imec
Business: Research and development of next-generation semiconductor technologies, systems and photovoltaics.
Established: Set up in 1984 by the government of Flanders, Belgium, with initial investment of 62 million euro and staff of 70
Head office: Leuven, Belgium
Representative: Luc Van den hove (President & CEO)
Staff: 1,895 (as of the end of 2010)
Website: http:// www.imec.be