Creation And Ordering Of Oxygen Vacancies At Wo3-Delta And Perovskite Interfaces

Changes in the structure and composition resulting from oxygen deficiency can strongly impact the physical and chemical properties of transition-metal oxides, which may lead to new functionalities for novel electronic devices. Oxygen vacancies (V-O) can be readily formed to accommodate the lattice mismatch during epitaxial thin film growth. In this paper, the effects of substrate strain and oxidizing power on the creation and distribution of V-O in WO3-delta thin films are investigated in detail. An O-18(2) isotope-labeled time-of-flight secondary-ion mass spectrometry study reveals that WO3-delta films grown on SrTiO3 substrates display a significantly larger oxygen vacancy gradient along the growth direction compared to those grown on LaAlO3 substrates. This result is corroborated by scanning transmission electron microscopy imaging, interface to accommodate interfacial tensile strain, leading to the ordering phases. The strain is gradually released and a tetragonal phase with much interface. The changes in the structure resulting from oxygen defect creation and optical properties of the films. which reveals a large number of defects close to the of V-O and the formation of semi-aligned Magneli better crystallinity is observed at the film/vacuum are shown to have a direct impact on the electronic and optical properties of the films.