A pilot investigation on laser annealing for thin-film solar cells: Crystallinity and optical properties of laser-annealed CdTe thin films by using an 808-nm diode laser
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Compared to conventional furnace and rapid thermal annealing, laser annealing for heterojunctioned thin-film solar cells has several advantages including excellent annealing selectivity to the under-layers with a localized high temperature for a short process time. A continuous wave 808-nm diode laser was used for the laser annealing process of CdTe thin films for various output powers. The grains in the laser-annealed CdTe thin films grew along the C (111), H (110), and C (311) planes. Laser annealing resulted in an increase in grain size and a decrease in surface roughness. The optical band gap energy of the CdTe thin films was affected directly by the grain size, showing 1.460 eV and 1.415 eV for the as-deposited and laser-annealed CdTe thin films, respectively. The absorbance of the CdTe thin films with better crystallinity showed an improved value of 99.5–99.9% in the visible spectral region after laser annealing at an output power of 0.91 W.
KeywordsCdTe Laser annealing 808-nm diode laser Sputtering
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- L. Schade, S. Franzka, S. Hardt, H. Wiggers and N. Hartmann, Appl. Surf. Sci. (2013) doi:10.1016/j.apsusc.2012.11.077.Google Scholar
- A. J. Al-Douri, F. Y. Al-Shakily, A. A. Alnajjar and M. F. A. Alias, Adv. Condens. Matter Phys. 2011, 910967 (2011).Google Scholar
- N. H. AI-Hardan, K. T. AI-Rasoul and S. A. Hussain, J. Al-Qadisiyah Pure Sci. 15, 1 (2010).Google Scholar
- J. C. Osuwa and N. I. Chigbo, Chalcogenide Lett. 9, 501 (2009).Google Scholar
- B. D. Cullity, Elements of X-Ray Diffraction, 3rd ed. (Addison-Wesley, Reading, Mass., London, 1967).Google Scholar
- A. Mahadkar, A. Chauhan, M. Thakurdesai and D. Gaikwad, in 2008 Physics Education Research Conference Part of the AIP Conference Proceedings series. Edmonton (Alberta, Canada, July 23–24, 2008), Chap. 1004, p. 305.Google Scholar