Growth of zinc oxide thin films on Y2O3/Si substrates by chemical vapor deposition

Abstract

Epitaxial ZnO was deposited on Si(1 1 1) substrate by atmospheric pressure metal-organic chemical vapor deposition (MOCVD) at 500 degrees C. A Y2O3 buffer layer in epitaxy with Si substrate has successfully suppressed the Si oxidation before ZnO deposition. The Y2O3 film was grown by pulsed laser deposition (PLD) on Si(1 1 1) substrate at 800 degrees C. Also, ZnO was deposited by PLD for comparison with MOCVD. X-ray diffraction and cross-sectional transmission electron microscopy was used to characterize microstructures of the ZnO films and their interfaces with Y2O3. The result shows ZnO(0 0 0 2) parallel to Y2O3(1 1 1). With the increase of the deposition time, the grain morphology of ZnO thin films evolved from flat structure to columnar structure. Most of the columnar ZnO grains are c-axis oriented perpendicular to the interface. (C) 2004 Elsevier B. V. All rights reserved.