Local heterostructure contacts

US7943416B2 · kind B2 · utility

Assignee

• Q-CELLS SE · DE

Inventors

• Maximilian Scherff · Dortmund, DE
• Wolfgang Fahrner · Gundelfingen, DE

Key dates

• Filing date: Aug 28, 2007
• Grant date: May 17, 2011
• Expiry date: Oct 26, 2027

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S977/755

Abstract

Disclosed is a novel method for creating local contacts in solar cells. In the method, a surface passivation that has been applied to a semiconductor substrate is locally etched away using a plasma process with the help of a thin stretched, elastic foil. If necessary, deep doping gradients are then locally created at the same points by means of a hydrogen plasma treatment with the help of thermal donors so as to increase the diffusion length of the charge carriers in the direction of the contacts. Finally, local heterostructure contacts are applied through the same mask openings. The contacts are characterized by a much lower saturation current than common diffused contacts and are therefore particularly suitable for high-performance solar cells.