• Research project Las VeGaS reaches important milestone after only six months
• The manufacturing technology used can reduce the costs of front side metallization by over 50 percent
• Development successes to be transferred over to monocrystalline technology
Mainz, November 25, 2011 – SCHOTT Solar AG and its project partners have already reached an important milestone in the research project Las VeGaS after only six months: a solar cell metalized with copper achieved an efficiency of 18.0 percent. A multicrystalline wafer from SCHOTT Solar AG that features standard screen-printed backside metallization serves as the basis. The goal of the Las VeGaS project is to largely replace the silver contacts that are commonly used on the front side of solar cells with less expensive nickel-copper plating. This would lower the manufacturing costs of front side metallization by more than half. SCHOTT Solar is working together with RENA GmbH and CiS Forschungsinstitut für Mikrosensorik und Photovoltaik GmbH in order to achieve this.
The special challenge involved in metalizing with nickel-copper plating is to prevent diffusion of the copper into the silicon solar cell, as this would reduce the carrier lifetime of the electrons and thus reduce the efficiency of the cell. For this reason, the project team has developed an electroplated nickel layer that serves as a diffusion barrier as well as the appropriate manufacturing techniques for applying both then nickel barrier and the copper contacts to the cell.
The project team has used the new “InCellPlate” technology of RENA to manufacture rather promising prototypes on standard industrial tools. These solar cells will now be used to fabricate test modules so that they can demonstrate their long-term stability in reliability tests. Furthermore, the project team is working on transfering these development successes to monocrystalline cells. Efficiency that exceeds 19 percent are expected.
The Las VeGaS method offers yet another advantage besides the lower costs for the raw material copper: the electroplated layers are environmentally friendly because they are free from both lead and solvents and thus meet the requirements of the European Union’s RoHS Directive. This places restrictions on the use of hazardous substances in electrical and electronic devices.
It is now no longer necessary to use large amounts of expensive silver paste, because only a very thin electroplated silver layer is needed to solder the cells to the copper tabs to make a module. This, in turn, lowers the consumption of silver by at least 95 percent.
About the project partners
SCHOTT Solar, with its headquarters in Mainz, manufactures solar wafers, cells and modules and is a quality leader by international comparison. RENA GmbH, Gütenbach/Freiburg, is one of the largest suppliers of process technology for wet chemical applications, mainly for use in the photovoltaic industry. CiS Forschungsinstitut für Mikrosensorik und Photovoltaik GmbH from Erfurt is an institution dedicated to application-oriented research and development in the areas of silicon-based sensor technology, microsystems technology and photovoltaics. CiS serves both the public sector and industry, mainly SMEs. The Las VeGaS project that focuses on the long-term stability of front side metallization of solar cells using environmentally friendly electroplated layers, receives funding support from the Federal Ministry of Education and Research as part of the “Innovation Alliance on Photovoltaics”.
Further information is available under www.schottsolar.de
You’ll also find this press release under http://www.ffpress.net/Kunde/SOL/
SCHOTT Solar, with its high-quality products, enables the potential of the sun as a nearly inexhaustible source of energy to be utilized. And it’s for exactly that reason that SCHOTT Solar produces important components for photovoltaic applications and solar energy plants. In the photovoltaic industry, the company is one of the few integrated manufacturers of crystalline silicon wafers, cells and modules. In thin-film technology, SCHOTT Solar also describes itself as an advanced supplier due to having over twenty years of experience. And in the production of receivers for solar power plants, SCHOTT Solar sees itself as a market and technology leader. The receivers are key components in large-scale power plants that generate electricity from solar energy centrally on the basis of parabolic trough technology and are able to supply entire cities with power. SCHOTT Solar has production facilities in Germany, the Czech Republic, the USA and Spain. The innovative power and technological competence of the company date back to the late 1950s. SCHOTT Solar is a wholly owned subsidiary of the international SCHOTT technology group. SCHOTT develops special materials, components and systems for the household appliance, pharmaceutical, solar energy, electronics, optical and automotive industries. With around 17,500 employees, the SCHOTT Group generated a worldwide turnover of about 2.9 billion euros in fiscal year 2009/2010.
Contact:
SCHOTT AG
Christina Rettig
PR Manager
Phone: +49 (0)6131 – 66 4094
Fax: +49 (0)3641 – 28889141
christina.rettig@schott.com
www.schottsolar.de
Fink & Fuchs Public Relations AG
Alexandra Mainka
Agency
Phone: +49 (0)611 – 74131 86
Fax: +49 (0)611 – 74131 30
alexandra.mainka@ffpr.de
www.ffpress.net
