Epitaxial growth of Pt(001) thin films on MgO(001) under oxidizing conditions

View/ Open
Date
1993Author
Cui, G.
Van Buskirk, P. C.
Zhang, J.Beetz, C. P., Jr.
Steinbeck, J.
Wang, Z. L. (Zhong Lin)
Bentley, J.
Metadata
Show full item recordAbstract
Epitaxial Pt(001) thin films have been grown on MgO(001) substrates using dc magnetron sputtering with an Ar/O₂ mixture at 700°C. The width (FWHM) of the rocking curve of the Pt(002) peak is between 0.16° and 0.20°, which is only 0.05° wider than that of the MgO (002) peak of the cleaved substrate. The film surface roughness is about 1 nm (rms) for a 240 nm thick Pt film. No grain structure could be observed using SEM. In contrast, the films deposited at 700 °C with pure Ar, have both Pt(111) and Pt(001) oriented growth, as shown by XRD Θ -2 Θ scans, with the Pt(111) peak having the largest intensity. BaTiO₃ epitaxial films have also been deposited on Pt(001)/MgO(001). The width (FWHM) of the rocking curve of the BaTiO₃(200) peak is 0.4°. The surface morphology of the epitaxial BaTiO₃(100) thin films on Pt(001)/MgO(001) is featureless. XRD pole figure measurements on PtIBaTiO₃/Pt trilayer shown a very good in-plane alignment of all layers. The epitaxial growth relationship was also confirmed by TEM electron diffraction and cross-section imaging. The Pt/BaTiO₃/Pt epitaxial trilayer could serve as a prototype for ferroelectric capacitors and may be able to improve the electrical properties of the capacitors.