Properties of ZnO / Al2 O 3 Alloy Films Grown Using Atomic Layer Deposition Techniques

Abstract

By varying the ratio of the constituents, compound films can exhibit a widely tunable range of physical properties. Atomic layer deposition (ALD) techniques are based on sequential, self-limiting surface reactions and can grow compound films. In this study, alloy films were prepared using ALD techniques. By adjusting the ALD pulse sequence, the alloy film composition was varied from 0-100% ZnO. These alloy films are expected to display varying properties because ZnO and have very different physical properties. For example, ZnO is a conductor and is an insulator. The physical properties of the alloys were explored using a variety of techniques. The growth rate, refractive index, composition, surface roughness, crystallinity, resistivity and density of the alloy films could be continuously tuned over the full range of values defined by the pure oxides. The refractive index varied from for pure ZnO to for pure The resistivity could be tuned over 18 orders of magnitude from Ω cm for pure ZnO to Ω cm for pure Anomalies in surface roughness and density vs. Zn content were observed at a Zn content of ∼76%. These anomalies were attributed, in part, to the etching of Zn by during the alloy film growth. © 2003 The Electrochemical Society. All rights reserved.