Low temperature deposition of epitaxial BaTiO3 films in a rotating disk vertical MOCVD reactor

Abstract

Epitaxial BaTiO3 thin films were deposited on MgO (100) in a rotating disk vertical metalorganic chemical vapor deposition (MOCVD) reactor at 700°C. The metalorganic sources used were titanium tetraisopropoxide and the highly volatile fluorinated barium precursor (Ba(hfa)2∙pentaethyleneglycolethylbutylether(PEB)). To facilitate growth at the lower temperature while suppressing the formation of BaF2 impurity phases, a strong oxidant consisting of a mixture of 80% N2O and 20% O2 was employed. The BaTiO3 films deposited at 700°C are phase pure and show only BaTiO3 {001} x-ray diffraction peaks. The x-ray rocking curve full width at half maximum (FWHM) of the BaTiO3 (002) peak was 0.82°. The fourfold symmetry and coincident position of the {110} peaks for both the film and substrate confirms in-plane epitaxy of cube-on-cube orientation. The Φ-scan FWHM of the BaTiO3 film is 1.05°. The growth temperature in this work is lower than the temperatures used in most comparable thermal MOCVD epitaxial oxide processes for BaTiO3.

Integration of BaTiO3 on Si (001) using MgO/STO buffer layers by molecular beam epitaxy

“…For comparison, a BTO film was also deposited on an MgO single crystal substrate during the same growth run. A similar roughness and morphology were observed and reported elsewhere for BTO on MgO substrates [17], which indicates that they do not result from the use of MgO/STO buffer layer. In order to investigate the microstructure and interface of individual layers, an XTEM analysis of the multilayer structure was conducted.…”

“…The BTO thin films were deposited using a rotating disk vertical MOCVD reactor. The details of the MOCVD process conditions, crystal quality, surface morphology of the BTO grown on MgO (0 0 1) have been reported elsewhere [17]. The major advantages of this reactor are: one, epitaxial BTO thin films are realized at temperatures lower than those used in most comparable thermal MOCVD oxide processes for BTO; second, the reactor enables deposition on large area substrates.…”

Defect and Interfacial Structure of Heteroepitaxial Fe3O4/BaTiO3 Bilayers

“…To fabricate the epitaxial Fe 3 O 4 /BaTiO 3 bilayer, the BaTiO 3 layer was first deposited on a MgO (001) substrate using a rotating disk MOCVD vertical reactor (Dhote et al, 2005). The BaTiO 3 deposition was initiated prior to the substrate reaching a steady-state temperature.…”

Hybrid molecular beam epitaxy for the growth of complex oxide materials

“…Homoleptic metal alkoxides (Ahn, Park, & Park, 2003;Boyd, Hirsch, Hubbard, & Cole, 2009;Burleson, Roberts, Gladfelter, Campbell, & Smith, 2002;Chen et al, 1993;Dhote et al, 2005;Nandi, Rhubright, & Sen, 1990;Roeder et al, 2000;Taylor et al, 1999;Teren, Belot, Edleman, Marks, & Wessels, 2000;Yoldas, 1977), a subset of coordination complexes consisting of a central metal ion bound to multiple identical organic groups via oxygen atoms (chemical formula: M(OR) n , where M is the metal ion and R is any of a variety of organic functional groups) are important MO precursors used for metal-oxide deposition. Atomic-layer deposition (ALD) and metal-organic chemical vapor deposition (MOCVD) techniques are the most well-known examples.…”