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Indexed by:Journal Papers

Date of Publication:2015-08-01

Journal:SOLAR ENERGY

Included Journals:SCIE、EI、Scopus

Volume:118

Page Number:384-389

ISSN No.:0038-092X

Key Words:n-type silicon solar cells; Screen-printing; SiO2 layer; Aluminum-alloyed emitter

Abstract:This paper reports on an industrially applicable approach to create efficient Al-doped p(+) regions alloyed from screen-printed pastes for the application as rear emitters in n-type silicon solar cells. The influences of polished and pyramidal rear surfaces on the formation of Si Al alloy and saturation current are discussed. We demonstrate that a thin SiO2 layer on Si Al interface can mitigate the inhomogeneous Al diffusion during alloying process and develop the transport properties. Furthermore, we apply this SiO2 layer in our n(+)np(+) solar cells, which exhibit lower series resistance and fine IQE response as a result of the improved Al emitter quality. For large-area n-type silicon solar cells (239 cm(2)) with a full-area Al-p(+) rear emitter, we achieved an 18.8% efficient cell with an open-circuit voltage of 637.4 mV. Remarkable gains of 1.6% on average efficiency, 0.8 mA/cm(2) on J(sc), 8.6 mV on open-circuit voltage and 4.1% on FF are obtained, comparing with the solar cells fabricated by standard industrial process. (C) 2015 Elsevier Ltd. All rights reserved.