Concrete solar cell

US5415700A · kind A · utility

Assignee

• State of Oregon acting by and through the State Board of Higher Ed. on Behalf of Oregon State Univ. · US

Inventors

• John R. Arthur · Grovetown, US
• Robert Kurt Graupner · Santa Clara, US
• Tyrus K. Monson · Corvallis, US
• James A. Van Vechten · Fryeburg, US
• Ernest G. Wolff · Lomita, US

Key dates

• Filing date: Dec 10, 1993
• Grant date: May 16, 1995
• Expiry date: Dec 10, 2013

Classification

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

Abstract

An inexpensive, robust concrete solar cell (10) comprises a photovoltaic material embedded in and extending beyond the major surfaces (16 and 18) of a matrix layer (14). The matrix layer typically comprises a high strength, cementitious material, such as a macrodefect free cement. The photovoltaic material comprises particles (12) of high-resistivity single crystal silicon, typically ball milled from ingot sections unsuitable for slicing into silicon wafers. The ingot sections include unprecipitated dissolved oxygen that is electrically activated by a low temperature annealing process to produce n-type silicon, even in silicon crystals that include a p-type dopant. An aluminum sheet (28), positioned on the backside of the matrix layer, is briefly melted together with the silicon particles to produce a p-type aluminum-doped silicon region (22) that forms a pn junction with the n-type region (24) of the particle. The aluminum sheet also provides the electrical contact to the p-type regions. The front surface of the matrix layer, from which the n-portion of the silicon particle protrudes, is covered with a translucent indium tin oxide conductive layer (30) that provides electrical con…