Atomic Layer Deposition of Antimony Oxide on Hydrogen-terminated Silicon Substrates

Abstract

Atomic layer deposition thin antimony oxide films on silicon substrates was investigated. Growth of small crystallites could be obtained by using triisopropylantimony (SbiPr3) and water. The deposition of thin continuous films succeeded after employing ozone and SbiPr3. The growth rate was significantly higher for the higher deposition temperature: 0.16 nm/cycle at 300 {degree sign}C compared to 0.06 nm/cycle at 200 {degree sign}C. X-ray photoelectron spectroscopy detected no impurities in the film other than adventitious carbon at surface. A composition ratio of antimony to oxide of 27/73 was found, suggesting the occurrence of the pentavalent oxide Sb2O5. The oxide is prone to sputter reduction during depth profiling. A chemical shift in the binding energy of the Sb photoemission peaks from the oxide to the Sb0 state clearly arises already after gentle argon sputtering. At temperatures up to 40 {degree sign}C the as-deposited films showed remarkably resistance to buffered oxide etch and nitric acid.