Critical thickness of single crystal fcc iron on diamond

• Published in: Surface science Vol. 326; no. 3; pp. 252 - 266
• Main Authors: Hoff, H.A., Waytena, G.L., Glesener, J.W., Harris, V.G., Pappas, D.P.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 20.03.1995; Amsterdam Elsevier Science; New York, NY
• Subjects: Condensed matter: structure, mechanical and thermal properties; Copper; Diamond; Exact sciences and technology; Extended X-ray absorption fine structure (EXAFS); Iron; Low index single crystal surfaces; Physics; Reflection high-energy electron diffraction (RHEED); Structure and morphology; thickness; Surface structure; Surface tension; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Extended X-ray absorption fine structure (EXAFS); Low index single crystal surfaces; Diamond; Iron; Surface tension; Copper; Reflection high-energy electron diffraction (RHEED); Surface structure; Diamonds; Elasticity; Crystal growth from vapors; RHEED; Experimental study; Critical phenomena; EXAFS; AES; Thickness; Thermal expansion; Multilayers; Transition elements; Mismatch lattice; SEM
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(94)00787-X

The growth of (100) diamond/iron/copper multilayer structures has been examined by reflection high energy electron diffraction, extended X-ray absorption fine structure, and scanning electron microscopy in an effort to determine the thickness limit for metastable face-centered-cubic Fe on (100) diamond. Both copper films deposited on iron layers with thicknesses below 1.4 nm and the iron layers themselves were found to be face-centered cubic single crystal, while films grown on iron that was 2.0 nm and thicker and the iron itself were found to be polycrystalline. This critical thickness range of 1.4–2.0 nm compares well with the theoretically calculated value of 1.8 nm. This value was determined using the mechanical equilibrium theories (Matthews-Blakeslee and van der Merwe) with a lattice parameter for face-centered cubic iron that was derived by estimating the functional form of the linear thermal expansion coefficient and extrapolating the Poisson's ratio for austenitic stainless steel to the temperature of interest. The shear modulus, and intrinsic stacking fault energy for fcc Fe from ∼ 1350°C down to below room temperature have also been estimated. A more likely room temperature lattice parameter for fcc Fe than is usually assumed was estimated to be 0.3579 nm. The measured in-plane lattice parameter of strained fcc Fe on diamond was 3.54 ± 0.1 A ̊ .