Trench process and structure for backside contact solar cells with polysilicon doped regions

US7851698B2 · kind B2 · utility

Assignee

• SUNPOWER CORPORATION · US

Inventors

• Denis De Ceuster · Woodside, US
• Peter John Cousins · Menlo Park, US
• David D. Smith · Dublin, US

Key dates

• Filing date: Feb 25, 2009
• Grant date: Dec 14, 2010
• Expiry date: Feb 25, 2029

Classification

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

Abstract

A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. An interrupted trench structure separates the P-type doped region from the N-type doped region in some locations but allows the P-type doped region and the N-type doped region to touch in other locations. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. Among other advantages, the resulting solar cell structure allows for increased efficiency while having a relatively low reverse breakdown voltage.