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FIZIKA A 11 (2002) 1 , 31-42
 
RAMAN AND PHOTOLUMINESCENCE STUDIES OF PURE AND Sn-ENRICHED THIN FILMS
OF CdS PREPARED BY SPRAY PYROLYSIS
I. K. BATTISHAa, H. H. AFIFYa, G. ABD EL FATTAHb
and Y. BADRb
aSolid State Physics Department, National Research Centre
(NRC), Cairo, Egypt
bNational Institute of Laser Enhancement Sciences (NILES),
Cairo University, Egypt
Received 10 September 2000; revised manuscript received 16 September
2001
Accepted 5 November 2001 Online 25 May 2002
Thin films of CdS, pure and enriched with different concentrations of tin up to 6%,
were prepared by the spray pyrolysis technique. All samples were prepared at the
deposition temperature of 420 °C. The XRD
diagnostic data of the investigated samples revealed the polycrystalline nature of the
as-deposited samples. The main characteristic peaks of CdS appeared in both pure and
enriched films prepared by all used methods. The enrichment of Sn has no effect on
positions of the characteristic peaks. The observed effect of Sn enrichment is the change
in peak broadening which increases with the increase of Sn concentration. The thickness
values ranged from 0.65 up to 1.15 mm. The samples of pure CdS
show a sharp absorption edge at about 2.43 eV. The absorption coefficient a of the investigated samples was calculated from transmission and
reflection spectra. Photoluminescence measurements show red emission band of the
as-deposited samples, which was quenched by Sn incorporation. This band is ascribed to the
excess of Cd which was checked by the energy dispersive X-ray (EDX) spectrometry. Raman
spectra of samples with different concentrations of Sn were studied. They show remarkable
increase of intensity when increasing the film thickness and decreasing the Sn
concentration.
PACS numbers: 78.30.-j, 78.66.-m, 68.55.Ln
UDC 538.958, 538.975
Keywords: pure and Sn-enriched CdS thin films, spray pyrolysis technique,
polycrystalline, light absorption coefficient, photoluminescence, Raman spectra
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