High UV Transparent Conductivity of SrMoO₃ Thin Films

Abstract

The perovskite oxide SrMoO 3 has attracted significant attention for its potential applications in ultraviolet (UV) transparent conductors. Thus far, synthesizing high-quality epitaxial SrMoO 3 thin films by pulsed laser deposition (PLD) is usually under highly reducing (Ar or Ar-H 2 gas mixture) atmospheres. Here, we grew SrMoO 3 epitaxial films using the PLD technique at a base pressure below 1 × 10 −5 Pa without any gas supply to optimize their optical and electrical properties. By depositing these films on the (001) SrTiO 3 , (001) LaAlO 3 , and (001) MgO substrates, the as-grown SrMoO 3 films, with a nominal lattice mismatch in the range of −4.8 to +5.7% and a thickness of 20−60 nm, show prominent transparent conductivity in both visible and UV wavelengths. All the films exhibit metallic-like conductivity, with a room-temperature resistivity varying from 10 to 60 μΩ•cm. The resistivity increases with decreasing thickness. Notably, we can achieve extremely high transmittance, exceeding 80% for wavelengths ranging from 300 to 500 nm, and a low resistivity of approximately 20 μΩ•cm in SrMoO 3 films as thin as 20 nm. The excellent UV transparent conducting properties that are insensitive to the substrate type and film thickness make SrMoO 3 films a promising material for various photoelectronic devices and energy-harvesting applications.