Band gap engineering of ZnO for high efficiency CIGS based solar cells
2010 (English)In: Oxide-based Materials and Devices / [ed] Teherani FH, Look DC, Litton CW, Rogers DJ, 2010, Vol. 7603, 76030-76039 p.Conference paper (Refereed)
Thin film solar cells based on Cu(In,Ga)Se2, called CIGS, is one of the most promising technologies for low cost, high efficiency photovoltaics. The CIGS device is composed of four layers; molybdenum back contact, CIGS p-type absorber, n-type buffer layer and doped ZnO top contact. The most common buffer layer is CdS, however it is desirable to find a Cd-free, large band gap alternative. In this paper, the use of ZnO-based buffer layers deposited by atomic layer deposition, ALD is described. Efficiencies of over 18% are shown by using Zn(O,S) or (Zn,Mg)O by ALD followed by sputtered ZnO:Al. The role of the conduction band alignment across the heterojunction is discussed, and results for large band gap CuGaSe2 absorbers are presented. In addition, light-soaking effects for devices with (Zn,Mg)O-based buffer layers are related to measurements of persistent photoconductivity of ALD-(Zn,Mg)O thin films.
Place, publisher, year, edition, pages
2010. Vol. 7603, 76030-76039 p.
, Proceedings of SPIE-The International Society for Optical Engineering, ISSN 0277-786X ; 7603
Cu(In, Ga)Se-2, solar cells, thin film, ZnO, band alignment
Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-133173DOI: 10.1117/12.846017ISI: 000284035700008ISBN: 978-0-8194-7999-0OAI: oai:DiVA.org:uu-133173DiVA: diva2:360294
Conference on Oxide-based Materials and Devices San Francisco, CA, JAN 24-27, 2010
band gap;high efficiency CIGS based solar cells;thin film solar cells;high efficiency photovoltaics;p-type absorber;n-type buffer layer;atomic layer deposition;conduction band alignment;heterojunction;light-soaking effects;photoconductivity;ZnO-CdS-Cu(InGa)Se2-Mo;2010-11-022010-11-022016-04-18Bibliographically approved