Preparation of aluminum oxide films at low temperatures by a hot wall technique

Abstract

Aluminum oxide (Al₂O₃) films were prepared on a Si(100) surface by a hot wall technique using aluminum iso-propoxide as a source material. The films could be deposited onto a Si(100) substrate at temperatures above 623K. The addition of water (H₂O) vapor during the deposition process was effective to reduce the substrate temperature to 523K in order to obtain Al₂O₃ films. The structures of the films were amorphous. The growth rate was between 0.016-0.108nm sec^-1 depending both on the substrate temperature and the presence of H₂O vapor. Although the as-deposited films prepared at substrate temperatures below 473K in the presence of H₂O vapor have stoichiometry close to Al₂O₃, they contained Al-OH bonds in them. Voltage vs. current characteristics of the films are also discussed.