Low-temperature deposition of meta-stable β-MoO3(011) epitaxial thin films using step-and-terrace substrates

Publication date: 30 November 2015
Source:Thin Solid Films, Volume 595, Part A
Author(s): Ryota Shimizu, Kuniko Yamamoto, Tohru Suzuki, Takeo Ohsawa, Susumu Shiraki, Taro Hitosugi
We demonstrated the epitaxial growth of meta-stable β-MoO3(011) thin films on SrTiO3(100), NdGaO3(110), and NdGaO3(001) substrates, using dc reactive magnetron sputtering. Low-temperature deposition at ~200°C resulted in the suppression of the formation of thermodynamically stable α-MoO3, and we observed the growth of a β-MoO3 phase with mixed orientation. In contrast, depositions on substrate surfaces with a step-and-terrace structure resulted in uniaxially oriented β-MoO3(011) epitaxial thin films. The step-and-terrace structures were found to play an important role in controlling the epitaxial growth behavior of β-MoO3 thin films.