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Title: Tb{sub 2}O{sub 3} thin films: An alternative candidate for high-k dielectric applications

We are reporting the growth and structural, optical, and dielectric properties of Tb{sub 2}O{sub 3}, a relatively unexplored high-k dielectric material. A pulsed-laser deposition technique was used to grow Tb{sub 2}O{sub 3} thin-films on four different substrates: Si(100), SrTiO{sub 3}(100), LaAlO{sub 3}(100), and MgO(100). High-resolution X-ray diffraction and transmission electron microscopy results confirmed that film growth in an oxygen-rich (10{sup −1 }Torr) environment yields nearly single-crystal C-phase films, while a low-oxygen (10{sup −6 }Torr) environment growth results in the formation of monoclinic polycrystalline B-phase films. Optical transmission measurements showed that the bandgap of Tb{sub 2}O{sub 3} is direct in nature with a value of 2.8 eV and 3.4 eV for the cubic and monoclinic phases, respectively. By measuring the capacitance of test devices, quite high dielectric constants of 13.5 and 24.9 were obtained for the B- and C-phase Tb{sub 2}O{sub 3} films, respectively.
Authors:
; ;  [1]
  1. Nanostructured Materials Research Laboratory, Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112 (United States)
Publication Date:
OSTI Identifier:
22402420
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 22; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINATES; CAPACITANCE; CRYSTAL GROWTH; DIELECTRIC MATERIALS; ENERGY BEAM DEPOSITION; LANTHANUM COMPOUNDS; LASER RADIATION; MAGNESIUM OXIDES; MONOCRYSTALS; OXYGEN; PERMITTIVITY; SILICON; STRONTIUM TITANATES; TERBIUM OXIDES; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION