Effect of Different Substrates on Properties of CeO₂ Thin Film Synthesized By Pulsed Laser Deposition

Kousar Jahan¹, Prem Kumari Verma¹, Sudersh Yadav¹, Prof. Ravi Kumar², Prof. K.V.R. Rao³

^1,3  Centre for Converging Technologies,UOR, Jaipur (Raj.),

 ²  NIT, Hamirpur (H.P.)

Email: kousarj@gmail.com

Abstract:

We report the growth characteristics of cerium oxide (CeO₂) films deposited by pulsed laser ablation on different single crystal substrate, (100) oriented silicon (Si) substrate and (0001) oriented Al₂O₃ substrate. Laser fluence, laser shots, substrate temperature, and oxygen pressure were same during deposition. The as-deposited films are characterized by X-ray diffraction (XRD), Photoluminescence spectroscopy and Atomic force microscopy (AFM), to investigate the effect of substrate on crystal structure, optical property and surface roughness of films. The XRD results indicated that the synthesized films had a cubic structure and highly oriented in the (111) direction on Si substrate and on Al₂O₃  substrate. Si (100) substrate produced tensile strain and Al₂O₃ (0001) substrate produced compressive  strain  on  deposited  film.  Photoluminescence  emission  bands  showed  variation  in position and intensity of bands on different substrate. The origin of CeO₂  PL was due to the electrons transition from Ce4f band to O2p band and the defect level (oxygen vacancy) to O2p band which is more in CeO₂/Al₂O₃. The surface topography of the films revealed by AFM discloses that the surface of film is less rough on Si (100) than Al₂O₃ (0001).

Keywords: CeO₂, Thin film, XRD, AFM, Photoluminescence.

References:

1.   CeO₂   thin films on Si (100) obtained by pulsed laser deposition. Cossarutto L.; Chaoui N.; Millon E.; Muller J.F.;

2.   Lambert J.; Alnot M., Applied Surface Science, Volume 126, Number 3, 352-355(4), 1998.
Synthesis and properties of ceria thin films prepared by pulsed laser deposition, Balakrishnan G, Kuppusami P, Sairam TN, Thirumurugesan R, Mohandas E, Sastikumar D., J Nanosci Nanotechnol. 9(9), 5421-4, 2009.