SOLAR CELL STRUCTURE WITH GRADED REFRACTIVE INDEX LENS

• Main Authors: LOWENTHAL, Mark M, ZHENG, Lixin, YOUNGBULL, Tricia, RAY, William J, SHOTTON, Neil O, LOCKETT, Vera N, KAMINS, Theodore I
• Format: Patent
• Language: English; French; German
• Published: 29.10.2014
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; SEMICONDUCTOR DEVICES; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

A PV panel uses an array of small silicon sphere diodes (10-300 microns in diameter) connected in parallel. The spheres are embedded in an uncured aluminum-containing layer, and the aluminum-containing layer is heated to anneal the aluminum-containing layer as well as p-dope the bottom surface of the spheres. A phosphorus-containing layer is deposited over the spheres to dope the top surface n-type, forming a pn junction. The phosphorus layer is then removed. A conductor is deposited to contact the top surface. Alternatively, the spheres are deposited with a p-type core and an n-type outer shell. After deposition, the top surface is etched to expose the core. A first conductor layer contacts the bottom surface, and a second conductor layer contacts the exposed core. A liquid lens material is deposited over the rounded top surface of the spheres and cured to provide conformal lenses designed to increase the PV panel efficiency.