AVS 49th International Symposium
    Surface Science Wednesday Sessions
       Session SS2-WeA

Paper SS2-WeA5
Thermal Stability of Thin Ti Films on Al Single Crystal Surfaces@footnote 1@

Wednesday, November 6, 2002, 3:20 pm, Room C-110

Session: Structure and Chemistry at Metal Surfaces
Presenter: C.V. Ramana, Montana State University
Authors: C.V. Ramana, Montana State University
R.J. Smith, Montana State University
B.S. Choi, Jeonju University, Korea
B.S. Park, Charles Evans & Associates
A. Saleh, Charles Evans & Associates
D. Jeon, Myongji University, Korea
Correspondent: Click to Email
Chemical roughness and alloy formation at metallic interfaces can significantly degrade the performance of multilayer thin film magnetic device structures. We have investigated the use of metal interlayers, one or two atoms thick, to stabilize the interface for ordered growth of metal films with minimal intermixing. Specifically, thin Ti interlayers have been used to stabilize the Fe-Al(100) interface, a system characterized by considerable interdiffusion at room temperature. The benefits of the interlayer concept are strongly coupled to the stability of the interlayer at elevated temperatures. In this investigation we have characterized the structure of thin Ti layers on Al single crystal surfaces as a function of temperature using Rutherford backscattering and channeling (RBS/c) and low-energy ion scattering (LEIS). The Ti layers are shown to be stable up to temperatures of about 400° C, at which point diffusion of Ti into the Al lattice occurs. LEIS measurements, combined with RBS show clearly that the Ti atoms move into the surface at these temperatures. Channeling measurements show that the Ti atoms sit on Al lattice sites as a substitutional impurity. The stability of the Ti film appears to increase with the packing density of the Al surface, being slightly more stable for the close-packed Al(111) surface, and diffusing into the more open Al(110) surface at a lower temperature. @FootnoteText@ @footnote 1@ Work supported by NSF Grant DMR-0077534.