Atomic layer deposition of Cr2O3 thin films: Effect of crystallization on growth and properties

• DOI: 10.1016/j.apsusc.2008.02.016
• Publication Date: 2008-02-15T12:53:39Z
• Authors: Aivar Tarre; Jaan Aarik; Hugo Mändar; Ahti Niilisk; Rainer Pärna; Raul Rammula; Teet Uustare; Arnold Rosental; Väino Sammelselg
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract Atomic layer deposition of Cr2O3 thin films from CrO2Cl2 and CH3OH on amorphous SiO2 and crystalline Si(1 0 0) and α-Al2O3( 1 1 ¯ 0 2 ) substrates was investigated, and properties of the films were ascertained. Self-limited growth with a rate of 0.05–0.1 nm/cycle was obtained at substrate temperatures of 330–420 °C. In this temperature range epitaxial eskolaite was formed on the α-Al2O3( 1 1 ¯ 0 2 ) substrates. The predominant crystallographic orientation in the epitaxial films depended, however, on the growth temperature and film thickness. Sufficiently thick films grown on the SiO2 and Si(1 0 0) substrates contained also the eskolaite phase, but thinner films deposited at 330–375 °C on these substrates were amorphous. The growth rate data of films with different phase composition allowed a conclusion that the crystalline phase grew markedly faster than the amorphous phase did. The amorphous, polycrystalline and epitaxial films had densities of 4.9, 5.1 and 5.1–5.3 g/cm3, respectively.