Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jun 15;14(12):3307.
doi: 10.3390/ma14123307.

Ellipsometry Study of CdSe Thin Films Deposited by PLD on ITO Coated Glass Substrates

Flavia P N Inbanathan  1 , Pawan Kumar  2 , Kiran Dasari  3 , Ram S Katiyar  3 , Jixin Chen  4 , Wojciech M Jadwisienczak  1
Affiliations

Ellipsometry Study of CdSe Thin Films Deposited by PLD on ITO Coated Glass Substrates

Flavia P N Inbanathan et al. Materials (Basel). .

Abstract

Cadmium selenide (CdSe) thin films were deposited on indium tin oxide (ITO) coated glass substrates using pulsed laser deposition (PLD) technique under different growth temperatures. Samples were investigated for their structural, morphological, and optical properties through X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-Vis-NIR spectroscopy. AFM analysis revealed that the surface roughness of the as-grown CdSe thin films increased with the increase in deposition temperature. The optical constants and film thickness were obtained from spectroscopic ellipsometry analysis and are discussed in detail. The optical band gap of the as-grown CdSe thin films, calculated from the Tauc plot analysis, matched with the ellipsometry measurements, with a band gap of ~1.71 eV for a growth temperature range of 150 °C to 400 °C. The CdSe thin films were found to have a refractive index of ~3.0 and extinction coefficient of ~1.0, making it a suitable candidate for photovoltaics.

Keywords: AFM; CdSe; PLD; Tauc plot; XRD; absorbance; band gap; ellipsometry.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
(a) XRD patterns of the CdSe thin films showing a wurtzite phase with a peak at (002) for samples deposited at 150 °C to 350 °C, and peak (110) for the sample deposited at 400 °C. (b) Growth temperature dependent XRD (002) peak position and its FWHM change for the CdSe thin films. The solid lines are a guide for the eyes.
Figure 2
Figure 2
AFM images of the CdSe thin films surface grown at (a) 150 °C, (b) 250 °C, and (c) 350 °C. (d) Growth temperature dependent grain size and surface roughness analysis for the CdSe thin films deposited at different growth temperatures. Solid lines are a guide for the eyes.
Figure 3
Figure 3
(a) Absorbance vs. wavelength and (b) transmittance vs. wavelength for CdSe thin films deposited on ITO/glass substrates at different temperatures.
Figure 4
Figure 4
(a) Tauc plot of CdSe thin films grown at different temperatures from 150 °C to 400 °C. Insert shows the example of fitting outcome for CdSe sample grown at 200 °C. (b) Growth temperature vs. Eg band gap energy obtained from (a).
Figure 5
Figure 5
(a–d) Dependence of refractive index n and (e–h) extinction coefficient κ vs. photon energy of CdSe samples grown at different temperatures.
Figure 6
Figure 6
(a–d) The absorption coefficient α vs. photon energy for CdSe thin films deposited at different growth temperatures.
Figure 7
Figure 7
(a–d). The dielectric function εr, εi parameters vs. photon energy of CdSe thin films deposited at different growth temperatures.
See this image and copyright information in PMC

References

    1. Zhang Z., Thung Y.T., Chen X., Wang L., Fan W., Ding W.L., Sun H. Study of Complex Optical Constants of Neat Cadmium Selenide Nanoplatelets Thin Films by Spectroscopic Ellipsometry. J. Phys. Chem. Lett. 2021;12:191–198. doi: 10.1021/acs.jpclett.0c03304. - DOI - PubMed
    1. Lade S.J., Uplane M.D., Lokhande C.D. Photoelectrochemical properties of CdX (X = S, Se, Te) films electrodeposited from aqueous and non-aqueous baths. Mater. Chem. Phys. 2001;68:36–41. doi: 10.1016/S0254-0584(00)00280-7. - DOI
    1. Olusola O.I., Echendu O.K., Dharmadasa I.M. Development of CdSe thin films for application in electronic devices. J. Mater. Sci. Mater. Electron. 2014;26:1066–1076. doi: 10.1007/s10854-014-2506-x. - DOI
    1. Zhao L., Hu L., Fang X. Growth and Device Application of CdSe Nanostructures. Adv. Funct. Mater. 2012;22:1551–1566. doi: 10.1002/adfm.201103088. - DOI
    1. Patel K.D., Jani M.S., Pathak V.M., Srivastava R. Deposition of CdSe thin films by thermal evaporation and their structural and optical properties. Chalcogenide Lett. 2009;6:279–286.

LinkOut - more resources