Study of CIGS Solar Cells Back Contact
- PDF / 1,148,454 Bytes
- 7 Pages / 612 x 792 pts (letter) Page_size
- 5 Downloads / 219 Views
lar Cells Back Contact Sylvain Marsillac and Himal Khatri MRS Proceedings / Volume 1012 / 2007 DOI: 10.1557/PROC1012Y0303
Link to this article: http://journals.cambridge.org/abstract_S1946427400037647 How to cite this article: Sylvain Marsillac and Himal Khatri (2007). Study of CIGS Solar Cells Back Contact. MRS Proceedings,1012, 1012Y0303 doi:10.1557/PROC1012Y0303 Request Permissions : Click here
Downloaded from http://journals.cambridge.org/OPL, IP address: 128.148.252.35 on 05 Sep 2012
Mater. Res. Soc. Symp. Proc. Vol. 1012 © 2007 Materials Research Society
1012-Y03-03
Study of CIGS Solar Cells Back Contact Sylvain Marsillac, and Himal Khatri Physics and Astronomy, Wright Center for Photovoltaic Innovation and Commercialization, University of Toledo, 2801 W. Bancroft Street, Mail Stop #111, Toledo, OH, 43606 ABSTRACT Molybdenum thin films were deposited by r.f. magnetron sputtering. The strain in the films was mostly tensile and varied, with the Argon pressure and the r.f. power, along a bell curve, reaching a maximum at 8 mTorr (80 W) and 6 mTorr (100 W). The grain size deduced from the X-Ray diffraction measurements (FWHM) decreased with increasing Argon pressure and, to a lower extent, with decreasing r.f power. The change in grain size, as well as in morphology, was confirmed by AFM imaging. Finally, the resistivity of the films was found to increase with increasing Argon pressure, while the films maintained good adhesion to the sodalime glass substrates for all Argon pressures and r.f. power. INTRODUCTION The method used to deposit a thin film is a critical parameter as it can change the properties of the film. It is certainly of importance when this thin film is used as the back contact of a solar cell. Various properties are expected from the back contact for a Cu(InGa)Se2 solar cell on soda-lime glass substrate: high conductivity, good adhesion to the substrate, chemical inertness, surface smoothness, coefficient of thermal expansion adapted to the soda-lime glass and to the Cu(InGa)Se2 thin film, good ohmic contact with the Cu(InGa)Se2 and allowance of sodium diffusion. Molybdenum thin films deposited by d.c. sputtering fulfill most of these requirements and excellent studies were done on these films (see for example Scofieldís work [1]). However, to our knowledge, few studies on the variation of the properties of molybdenum thin films deposited by r.f. magnetron sputtering have been done [2-8]. In this paper, we studied the mechanical, physical and electrical properties of molybdenum thin films deposited by r.f. magnetron sputtering as a function of two parameters: r.f. power and Argon pressure. EXPERIMENT Molybdenum thin films were deposited onto soda-lime glass substrates by r.f. magnetron sputtering under Argon pressure. Two parameters were varied: the r.f. power and the Argon pressure. The r.f. powers used were 80 W and 100 W. The Argon pressure in the chamber was varied from 4 mTorr to 12 mTorr, while the Argon gas flow was kept at 10 sccm. The deposition time was kept constant at 1 h
Data Loading...
