Finger structures protruding from absorber layer for improved solar cell back contact

US9306105B2 · kind B2 · utility

Assignee

• First Solar Malaysia SDN. BHD. · MY

Inventors

• Scott Daniel Feldman-Peabody · Golden, US
• Mark Jeffrey Pavol · Arvada, US
• Robert Dwayne Gossman · Aurora, US
• Bogdan Lita · Westborough, US
• Nathan Kruse · Colorado Springs, US
• John Milton Flood, III · Randolph, US
• Valerie Pflumio Hill · Denver, US

Key dates

• Filing date: Jul 31, 2013
• Grant date: Apr 5, 2016
• Expiry date: Sep 9, 2033

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/543

Abstract

Thin film photovoltaic devices that include a transparent substrate; a transparent conductive oxide layer on the transparent substrate; a n-type window layer on the transparent conductive oxide layer; a p-type absorber layer on the n-type window layer; and, a back contact on the p-type absorber layer are provided. The p-type absorber layer comprises cadmium telluride, and forms a photovoltaic junction with the n-type window layer. Generally, the p-type absorber layer defines a plurality of finger structures protruding from the p-type absorber layer into the back contact. The finger structures can have an aspect ratio of about 1 or greater and/or can have a height that is about 20% to about 200% of the thickness of the p-type absorber layer. Methods of forming such finger structures protruding from a back surface of the p-type absorber layer are also provided.