High rate (~7 nm/s), atmospheric pressure deposition of ZnO front electrode for Cu(In,Ga)Se2 thin-film solar cells with efficiency beyond 15%
Corresponding Author
Andrea Illiberi
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Correspondence: Andrea Illiberi, TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands.
E-mail: [email protected]
Search for more papers by this authorFrank Grob
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorCorne Frijters
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorPaul Poodt
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorRam Ramachandra
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorHans Winands
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorMarcel Simor
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorPieter Jan Bolt
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorCorresponding Author
Andrea Illiberi
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Correspondence: Andrea Illiberi, TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands.
E-mail: [email protected]
Search for more papers by this authorFrank Grob
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorCorne Frijters
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorPaul Poodt
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorRam Ramachandra
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorHans Winands
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorMarcel Simor
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorPieter Jan Bolt
TNO, Thin Film Technology, PO Box 6235, 5600 HE Eindhoven, The Netherlands
Search for more papers by this authorABSTRACT
Undoped zinc oxide (ZnO) films have been grown on a moving glass substrate by plasma-enhanced chemical vapor deposition at atmospheric pressure. High deposition rates of ~7 nm/s are achieved at low temperature (200 °C) for a substrate speed from 20 to 60 mm/min. ZnO films are highly transparent in the visible range (90%). By a short (~minute) post-deposition exposure to near-ultraviolet light, a very low resistivity value of 1.6·10−3 Ω cm for undoped ZnO is achieved, which is independent on the film thickness in the range from 180 to 1200 nm. The photo-enhanced conductivity is stable in time at room temperature when ZnO is coated by an Al2O3 barrier film, deposited by the industrially scalable spatial atomic layer deposition technique. ZnO and Al2O3 films have been used as front electrode and barrier, respectively, in Cu(In,Ga)Se2 (CIGS) solar cells. An average efficiency of 15.4 ± 0.2% (15 cells) is obtained that is similar to the efficiency of CIGS reference cells in which sputtered ZnO:Al is used as electrode. Copyright © 2013 John Wiley & Sons, Ltd.
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