Growth of thin, flat, epitaxial ( [formula omitted]) oriented gold films on c-cut sapphire

• Published in: Surface science Vol. 498; no. 1; pp. 168 - 174
• Main Authors: Kästle, G., Boyen, H.-G., Koslowski, B., Plettl, A., Weigl, F., Ziemann, P.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.02.2002; Amsterdam Elsevier Science; New York, NY
• Subjects: Aluminum oxide; Condensed matter: structure, mechanical and thermal properties; Diffusion; interface formation; Epitaxy; Exact sciences and technology; Gold; Growth; Metallic films; Niobium; Physics; Reflection high-energy electron diffraction (RHEED); Solid surfaces and solid-solid interfaces; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); X-ray scattering, diffraction, and reflection; Gold; Growth; Epitaxy; X-ray scattering, diffraction, and reflection; Metallic films; Niobium; Reflection high-energy electron diffraction (RHEED); Aluminum oxide; Crystal growth; Atomic force microscopy; VPE; Solid-solid interfaces; RHEED; Experimental study; Surface structure; Metallic thin films; Rutherford backscattering; Sapphire; Transition elements; Crystal nucleation; Crystal faces
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/S0039-6028(01)01685-5

A new growth procedure has been developed to prepare thin (<50 nm), flat (roughness ∼0.3–1 nm rms), epitaxial Au films on top of an insulating substrate without using a magnetic seedlayer. This could be obtained by depositing first a Nb seedlayer (⩽1 nm) at room temperature on top of c-cut sapphire followed by evaporating Au at a rate of 0.05–0.1 nm/s at 300 °C. This procedure resulted in (1 1 1) oriented flat Au films even for thickness well below 50 nm. The flatness of these films was consistently confirmed by atomic force and scanning tunneling microscopy, their excellent epitaxial quality (rocking width 0.1°–0.3°) by X-ray diffractometry and reflected high energy electron diffraction.