Year 2017, Volume 1 , Issue 3, Pages 120 - 128 2017-12-13

Properties of SnO2:F thin films prepared by using HF or NH4F after exposure to atmosphere

Shadia IKHMAYİES [1]


Nanocrystalline fluorine doped tin oxide (SnO2:F) thin films were produced by the spray pyrolysis technique (SP) on glass substrates at a substrate temperature Ts = 450 °C. The hydrated stannous chloride (SnCl2.2H2O) was used as a precursor and ammonium fluoride (NH4F) was used as the doping compound for one set of films, and hydrofluoric acid (HF) was used as the doping compound to produce another set of films. After exposure to atmosphere for about one month, a comparison between the compositional, morphological and optical properties of the films obtained by using the two doping compounds was performed by using scanning electron microscope (SEM) observations, X-ray energy dispersive spectroscopy (EDS) and transmittance measurements. Both sets of films are found to be oxygen rich, but the films prepared by using NH4F have higher oxygen content. SEM images showed that the films prepared by using HF have larger grain size, and EDS analysis showed that these films have higher fluorine to oxygen ratio. In addition, the films prepared by using HF have lower transmittance and higher direct optical bandgap energy. These results are interesting for the use of SnO2:F  as a fore contact in CdS/CdTe solar cells.

Transparent conducting oxides, Spray pyrolysis, Doping, CdS/CdTe solar cells
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Subjects Materials Science, Multidisciplinary
Journal Section Research Articles
Authors

Orcid: orcid.org/0000-0002-2684-3300
Author: Shadia IKHMAYİES (Primary Author)
Institution: Al Isra University
Country: Jordan


Dates

Publication Date : December 13, 2017

Vancouver Ikhmayies S . Properties of SnO2:F thin films prepared by using HF or NH4F after exposure to atmosphere. Journal of Energy Systems. 2017; 1(3): 120-128.