Study of optical and structural properties of Cu2ZnSnS4 thin films

THIN SOLID FILMS

卷:519

Article; Proceedings Paper

Leitao, J. P.^1,2  Santos, N. M.^1,2  Fernandes, P. A.^1,2,3  Salome, P. M. P.^1,2  da Cunha, A. F.^1,2  Gonzalez, J. C.⁴  Matinaga, F. M.⁴ 

[1] Univ Aveiro, Dept Fis, P-3810193 Aveiro, Portugal

[2] Univ Aveiro, I3N, P-3810193 Aveiro, Portugal

[3] Inst Politecn Porto, Inst Super Engn Porto, Dept Fis, P-4200072 Oporto, Portugal

[4] Univ Fed Minas Gerais, Dept Fis, BR-30123970 Belo Horizonte, MG, Brazil

关键词: Cu2ZnSnS4;    Thin films;    Sulphurization;    Photoluminescence;    Potential fluctuations;   

DOI  :  10.1016/j.tsf.2010.12.105

来源: Elsevier

【 摘 要 】

Cu2ZnSnS4 is a promising semiconductor to be used as absorber in thin film solar cells. In this work, we investigated optical and structural properties of Cu2ZnSnS4 thin films grown by sulphurization of metallic precursors deposited on soda lime glass substrates. The crystalline phases were studied by X-ray diffraction measurements showing the presence of only the Cu2ZnSnS4 phase. The studied films were copper poor and zinc rich as shown by inductively coupled plasma mass spectroscopy. Scanning electron microscopy revealed a good crystallinity and compactness. An absorption coefficient varying between 3 and 4 x 10(4)cm(-1) was measured in the energy range between 1.75 and 3.5 eV. The band gap energy was estimated in 1.51 eV. Photoluminescence spectroscopy showed an asymmetric broad band emission. The dependence of this emission on the excitation power and temperature was investigated and compared to the predictions of the donor-acceptor-type transitions and radiative recombinations in the model of potential fluctuations. Experimental evidence was found to ascribe the observed emission to radiative transitions involving tail states created by potential fluctuations. (C) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

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