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Title: Epitaxial LaAlO{sub 3} thin film on silicon: Structure and electronic properties

Abstract

Epitaxial LaAlO{sub 3} films have been grown on Si (001) by molecular beam epitaxy with an ultrathin SrTiO{sub 3} seed layer. High resolution x-ray diffraction and transmission electron microscopy show the high quality epitaxial structure of LaAlO{sub 3} films, and the epitaxial relationship of LaAlO{sub 3} with Si is LaAlO{sub 3}(001)(parallel sign)Si(001) and LaAlO{sub 3}[100](parallel sign)Si[110]. The band gap of epitaxial LaAlO{sub 3} films was measured to be 6.5{+-}0.1 eV from O 1s loss spectra. Band offsets between crystalline LaAlO{sub 3} films and Si were determined to be partitioned equally with 2.86{+-}0.05 eV for valence-band offset and 2.52{+-}0.1 eV for conduction-band offset by using x-ray photoelectron spectroscopy.

Authors:
; ; ; ; ; ;  [1];  [2];  [3];  [3]
  1. Department of Physics, National University of Singapore, Singapore 117542 (Singapore)
  2. (United States)
  3. (Singapore)
Publication Date:
OSTI Identifier:
20971900
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 18; Other Information: DOI: 10.1063/1.2736277; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINATES; CRYSTAL GROWTH; ENERGY GAP; LANTHANUM COMPOUNDS; LAYERS; MOLECULAR BEAM EPITAXY; RESOLUTION; SILICON; STRONTIUM TITANATES; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Mi, Y. Y., Yu, Z., Wang, S. J., Lim, P. C., Foo, Y. L., Huan, A. C. H., Ong, C. K., Freescale Semiconductor, Inc. Tempe, Arizona 85284, Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602, and Department of Physics, National University of Singapore, Singapore 117542. Epitaxial LaAlO{sub 3} thin film on silicon: Structure and electronic properties. United States: N. p., 2007. Web. doi:10.1063/1.2736277.
Mi, Y. Y., Yu, Z., Wang, S. J., Lim, P. C., Foo, Y. L., Huan, A. C. H., Ong, C. K., Freescale Semiconductor, Inc. Tempe, Arizona 85284, Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602, & Department of Physics, National University of Singapore, Singapore 117542. Epitaxial LaAlO{sub 3} thin film on silicon: Structure and electronic properties. United States. doi:10.1063/1.2736277.
Mi, Y. Y., Yu, Z., Wang, S. J., Lim, P. C., Foo, Y. L., Huan, A. C. H., Ong, C. K., Freescale Semiconductor, Inc. Tempe, Arizona 85284, Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602, and Department of Physics, National University of Singapore, Singapore 117542. Mon . "Epitaxial LaAlO{sub 3} thin film on silicon: Structure and electronic properties". United States. doi:10.1063/1.2736277.
@article{osti_20971900,
title = {Epitaxial LaAlO{sub 3} thin film on silicon: Structure and electronic properties},
author = {Mi, Y. Y. and Yu, Z. and Wang, S. J. and Lim, P. C. and Foo, Y. L. and Huan, A. C. H. and Ong, C. K. and Freescale Semiconductor, Inc. Tempe, Arizona 85284 and Institute of Materials Research and Engineering, 3 Research Link, Singapore 117602 and Department of Physics, National University of Singapore, Singapore 117542},
abstractNote = {Epitaxial LaAlO{sub 3} films have been grown on Si (001) by molecular beam epitaxy with an ultrathin SrTiO{sub 3} seed layer. High resolution x-ray diffraction and transmission electron microscopy show the high quality epitaxial structure of LaAlO{sub 3} films, and the epitaxial relationship of LaAlO{sub 3} with Si is LaAlO{sub 3}(001)(parallel sign)Si(001) and LaAlO{sub 3}[100](parallel sign)Si[110]. The band gap of epitaxial LaAlO{sub 3} films was measured to be 6.5{+-}0.1 eV from O 1s loss spectra. Band offsets between crystalline LaAlO{sub 3} films and Si were determined to be partitioned equally with 2.86{+-}0.05 eV for valence-band offset and 2.52{+-}0.1 eV for conduction-band offset by using x-ray photoelectron spectroscopy.},
doi = {10.1063/1.2736277},
journal = {Applied Physics Letters},
number = 18,
volume = 90,
place = {United States},
year = {Mon Apr 30 00:00:00 EDT 2007},
month = {Mon Apr 30 00:00:00 EDT 2007}
}
  • The metal-insulator transition (MIT) in strong correlated electron materials can be induced by external perturbation in forms of thermal, electrical, optical, or magnetic fields. We report on the DC current induced MIT in epitaxial Sm{sub 0.6}Nd{sub 0.4}NiO{sub 3} (SNNO) thin film deposited by pulsed laser deposition on (001)-LaAlO{sub 3} substrate. It was found that the MIT in SNNO film not only can be triggered by thermal, but also can be induced by DC current. The T{sub MI} of SNNO film decreases from 282 K to 200 K with the DC current density increasing from 0.003 × 10{sup 9} A•m{sup −2}more » to 4.9 × 10{sup 9} A•m{sup −2}. Based on the resistivity curves measured at different temperatures, the MIT phase diagram has been successfully constructed.« less
  • The refractive indices and optical birefringence of the films were measured as a function of wavelength using the film-prism coupling method. Both the ordinary and extraordinary refractive indices for films grown on MgO(001) and LaAlO{sub 3}(001) were higher than that of single-crystal PbTiO{sub 3}; however, the optical birefringence of films grown on MgO(001) was reduced from that of the bulk. For films grown on SrTiO{sub 3}(001), the ordinary refractive index was very close to that of single-crystal PbTiO{sub 3}. We correlate the refractive index values and the reduced birefringence to the degree of residual strain and the volume fraction ofmore » 90{degree} domains in the samples, respectively. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.« less
  • LaAlO{sub 3} epitaxial films with La:Al cation ratios ranging from 0.9 to 1.2 were grown on TiO{sub 2}-terminated SrTiO{sub 3} (001) substrates by off-axis pulsed laser deposition. Although all films are epitaxial, rocking curve measurements show that the crystallographic quality degrades with increasing La:Al ratio. Films with La:Al ratios of 0.9, 1.0, and 1.1 were coherently strained to the substrate. However, the out-of-plane lattice parameter increases over this range, revealing a decrease in film tetragonality. Although all film surfaces exhibit hydroxylation, the extent of hydroxylation is greater for the La-rich films. Rutherford backscattering spectrometry reveals that La from the filmmore » diffuses deeply into the SrTiO{sub 3} substrate and secondary-ion-mass spectroscopy shows unambiguous Sr outdiffusion into the films.« less
  • Lead titanate (PbTiO{sub 3}) thin film has been deposited on lathanum aluminate LaAlO{sub 3}(100) (using pseudocubic index) single crystalline substrate by metal organic chemical vapor deposition at 550{endash}700thinsp{degree}C. Microstructure of the films has been studied by the four-circle x-ray diffraction and transmission electron microscopy methods. Due to the noncubic symmetry of the LaAlO{sub 3} substrate at room temperature, the grown films exhibited more complex domain structure than those grown on cubic MgO or SrTiO{sub 3} substrates. The x-ray pole figure of LaAlO{sub 3} pseudocubic (002) peak has revealed two separate peaks at room temperature, indicating the existence of the twomore » types of domain in the substrate. Consequently, the epitaxially grown PbTiO{sub 3} films were found to exhibit two distinguishable {ital c} domains, and eight {ital a}-domain peaks, as demonstrated by the x-ray pole figures employing PT(002) and PT(200) Bragg peaks. The domain structure and the domain formation mechanism are discussed in this article. {copyright} {ital 1999 American Institute of Physics.}« less
  • We report temperature and magnetic field dependences of the longitudinal and transverse magnetoresistances of high-quality epitaxial SrRuO{sub 3} thin films. We also report Hall effect measurements in the paramagnetic and ferromagnetic states. The magnetic field dependence of the longitudinal magnetoresistivity shows a simple scaling {approximately}{ital H}{sup 2}/({ital T}{minus}{ital T}{sub {ital c}}){sup 2} far above the ferromagnetic transition temperature {ital T}{sub {ital c}}. This observation supports a presence of localized magnetic moments above {ital T}{sub {ital c}}. {copyright} {ital 1996 The American Physical Society.}