Effect of annealing on pulsed laser deposited zirconium oxide thin films

• Published in: Journal of alloys and compounds 2011-09, Vol.509 (39), p.9536-9541
• Main Authors: Al-Kuhaili, M.F., Durrani, S.M.A.
• Format: Article
• Language: English
• Subjects: Annealing; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Defects; Deposition; Exact sciences and technology; Laser deposition; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Nanocrystals; Optical properties; Physics; Pulsed laser deposition; Pulsed lasers; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Theory and models of film growth; Thin film structure and morphology; Thin films; Zirconium oxide; Zirconium oxides
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2011.07.062

► ZrO 2 thin films were prepared by excimer pulsed laser deposition. ► The films were annealed in air in the temperature range 400–800 °C. ► Structural and chemical analyses were performed to characterize the films properties. ► The optical constants and band gap of the films were determined. Zirconium oxide thin films were deposited using pulsed laser ablation from a ceramic ZrO 2 target on unheated substrates. Subsequently, the films were annealed in air in the temperature range 400–800 °C. The films were characterized by X-ray diffraction, atomic force microscopy, X-ray photoelectron spectroscopy, and optical spectroscopy to investigate the variation of the structural, chemical, and optical properties upon annealing. As-deposited films were amorphous and had a large surface density of ablated particles. Annealing resulted in the growth of monoclinic nano-crystalline, uniform, and transparent films that were slightly sub-stoichiometric. The annealed films were compact and had high values of the refractive index. Extinction coefficients were small, and may be related to the presence of defects. The films exhibited the presence of an indirect band gap, related to defects, and a direct band gap, related to fundamental absorption.