Anti-ThCr2Si2typeRE2O2Sb (RE= rare earth) with a Sb square net has shown insulating conduction so far. Here we report the synthesis of La2O2Sb epitaxial thin films for the first time by multilayer solid-phase epitaxy. The valence state of Sb was about −2 evaluated from X-ray photoemission spectroscopy measurement, and the indirect band gap of 0.17 eV was observed. The La2O2Sb epitaxial thin film showed unexpectedly high electrical conduction as a narrow gap semiconductor, whose resistivity at room temperature was approximately ten-thousand-fold lower than that of La2O2Sb bulk polycrystal, attributed to increased carrier mobility probably due to suppressed Sb dimerization.
ASJC Scopus subject areas
- Materials Chemistry