Method of controlling the amount of Cu doping when forming a back contact of a photovoltaic cell

US9117956B2 · kind B2 · utility

Assignee

• First Solar, Inc. · US

Inventors

• Laura Anne Clark · Brighton, US
• Tammy Jane Lucas · Highlands Ranch, US
• Wyatt Keith Metzger · Louisville, US
• Samuel H. Demtsu · Thornton, US
• David Joseph Dickerson · Thornton, US
• Laura Jean Wilson · Peyton, US
• Mehran Sadeghi · Orpington, GB

Key dates

• Filing date: Aug 31, 2012
• Grant date: Aug 25, 2015
• Expiry date: Sep 24, 2032

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P70/50

Abstract

Methods for preparing an exposed surface of a p-type absorber layer of a p-n junction for coupling to a back contact in the manufacture of a thin film photovoltaic device are provided. The method can include: applying a treatment solution onto the exposed surface defined by the p-type absorber layer of cadmium telluride; and annealing the device with the p-type absorber layer in contact with the treatment solution to form a tellurium-enriched region in the p-type absorber layer at the exposed surface. The treatment solution comprises a chlorinated compound component that is substantially free from copper, a copper-containing metal salt, and a solvent.