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Download or read book Characterization of Native Point Defects in Barium Strontium Titanate written by Kyle Marshall McNicholas and published by . This book was released on 2012 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: In this study Ba0.5Sr0.5TiO3 (BST) thin films were grown on (100) oriented SrTiO3 (STO) substrates using molecular beam epitaxy. The BST films were produced under varying conditions with substrate temperature ranging from 700 °C to 900 °C, nominal oxygen background pressures ranging from ~0 Torr to 1E-6 Torr, and with an oxygen environment ranging from a 200 W plasma to an ambient O2 atmosphere. The films were analyzed using a multitude of techniques including depth resolved cathodoluminescence spectroscopy (DRCLS) surface photovoltage spectroscopy (SPS), atomic force microscopy (AFM), and x-ray diffraction (XRD). The DRCLS spectra obtained from the films display well-resolved emissions at 1.9 eV, 2.1 eV, 2.26 eV, 2.95 eV, and 3.5 eV. Surface photovoltage spectroscopy results correlate well with the emissions observed in the DRCLS and allow for the assignment of the positions of these defect states within the BST band gap. Furthermore, several trends are observed correlating the nature of the 2.9 eV emission to an oxygen related defect.