Growth and properties of amorphous thin films of the Al2O3–Y2O3 system

• Published in: Thin solid films Vol. 497; no. 1-2; pp. 65 - 71
• Main Authors: Kuo, D.H., Chen, W.R.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 21.02.2006; Elsevier Science
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Deposition by sputtering; Dielectric properties; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electrical properties and measurements; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Oxides; Permittivity (dielectric function); Physics; Sputtering; Oxides; Electrical properties and measurements; Dielectric properties; Sputtering; Temperature dependence; Amorphous material; Inorganic compounds; Point defects; Films; Growth rate; Transition element compounds; Binary compounds; Experimental study; Magnetrons; Morphology; Breakdown; Chemical composition; Performance; Permittivity; Current density; Radiofrequency sputtering; Yttrium oxides; Aluminium oxides; X-ray photoelectron spectra
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2005.09.185

Thin films of the aluminum oxide (Al2O3)-yttrium oxide (Y2O3) system including Al2O3, Y2O3, and mixed Al2O3–Y2O3 were prepared by radio-frequency magnetron sputtering using ceramic targets of Al2O3, Y2O3, and Al2O3–Y2O3 with different Y2O3/(Al2O3+Y2O3) molar ratios. These films were deposited at different substrate temperatures. The low-Y2O3 composite films had growth rate insensitive to deposition temperature, while a decreased rate at high temperature for the rest of films. The growth rates ranged 0.13–0.35 μm/h. Composition, growth morphology, dielectric properties, and electrical properties were investigated. The mixed-oxide films of the Al2O3–Y2O3 system had a varied dielectric constant of 8–13.5, a loss tangent of ∼0.05, leakage current density of ∼10−6 A/cm2 at 80 kV/cm, and varied breakdown strength of 2.2–4.8 MV/cm, depending upon the Y2O3 amount. Point defects in pure Y2O3 films are the reason for degraded dielectric performance.