Monolithic voltage-matched tandem photovoltaic cell and method for making same

US5261969A · kind A · utility

Assignee

• The Boeing Company · US

Inventor

• Billy J. Stanbery · Seattle, US

Key dates

• Filing date: Apr 14, 1992
• Grant date: Nov 16, 1993
• Expiry date: Apr 14, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/541

Abstract

A monolithic photovoltaic cell (20) that includes at least one upper cell (24) and two or more lower cells (26) is disclosed. The upper cell is separated from the lower cells by an intrinsic isolation layer (28) to which both the upper and lower cells are bonded. A conductive backplane (30) formed integrally with the upper cell serves as a member of that cell and is actually bonded to the intrinsic isolation layer. Each lower cell is provided with a conductive backplane (32) that functions as the interface between the cell and the intrinsic isolation layer. A selectively applied metallization layer (31) series connects the lower tandem cells together and connects the lower cells in parallel across the upper cell. Dielectric material (48) is applied between the individual photovoltaic cells (24, 26) and the metallization layer to prevent the metallization layer from shorting out the photovoltaic cells. In one embodiment of the invention, the upper photovoltaic cell may be an AlGaAs homojunction photovoltaic cell, the lower cells may be CuInSe.sub.2 /CdZnS heterojunction photovoltaic cells, and a layer of ZnSe may serve as the isolation layer between the cells. In one version of this…