Title :
High-quality cadmium stannate transparent conductive oxide film for tandem thin-film solar cells
Author :
Wu, X. ; Dhere, R.G. ; Zhou, J. ; Duda, A. ; Perkins, C. ; Yan, Y. ; Moutinho, H.R.
Author_Institution :
Nat. Renewable Energy Lab., Golden, CO, USA
Abstract :
In tandem thin-film solar cells with a superstrate device structure, the front transparent conductive oxide (TCO) contact needs high transmission and high conductivity for top cells, as well as higher transmission at the near-infrared wavelength region for bottom cells. Unfortunately, conventional TCOs (such as ITO, SnO/sub 2/, and ZnO) cannot completely meet these requirements. We developed a high-quality cadmium stannate (Cd/sub 2/SnO/sub 4/ or CTO) TCO film, which has transmission of 80%-90% in the region of 400-1300 nm and bulk resistivity of /spl sim/1.8/spl times/10/sup -4/ /spl Omega/ cm. In the CdTe/CIS tandem thin-film solar cell, the short-circuit current density (J/sub sc/) loss due to CTO film absorption can be reduced to only 0.6 mA/cm/sup 2/ and /spl sim/1.0 mA/cm/sup 2/ for the top cell and bottom cell, respectively.
Keywords :
cadmium compounds; copper compounds; electrical conductivity; electrical resistivity; indium compounds; infrared spectra; semiconductor thin films; short-circuit currents; solar cells; ternary semiconductors; transparency; wide band gap semiconductors; 400 to 1300 nm; CTO film absorption; Cd/sub 2/SnO/sub 4/; CdTe-CuInSe/sub 2/; bulk resistivity; conductivity; near-infrared wavelength region; optical transmission; short-circuit current density; superstrate device structure; tandem thin-film solar cells; transparent conductive oxide film;
Conference_Titel :
Photovoltaic Energy Conversion, 2003. Proceedings of 3rd World Conference on
Conference_Location :
Osaka, Japan
Print_ISBN :
4-9901816-0-3
