AVS 53rd International Symposium
    Advanced Surface Engineering Thursday Sessions
       Session SE-ThA

Paper SE-ThA2
Microstructure and Surface Properties of Ti-Si-C Nanocomposite Thin Films Deposited by dc Magnetron Sputtering

Thursday, November 16, 2006, 2:20 pm, Room 2007

Session: Hard and Nanocomposite Coatings: Synthesis, Structure, and Properties
Presenter: P. Eklund, Linköping University, Sweden
Authors: P. Eklund, Linköping University, Sweden
J. Emmerlich, Linköping University, Sweden
J. Frodelius, Linköping University, Sweden
C. Virojanadara, Linköping University, Sweden
L.I. Johansson, Linköping University, Sweden
O. Wilhelmsson, Uppsala University, Sweden
U. Jansson, Uppsala University, Sweden
H. Hogberg, Linköping University, Sweden
L. Hultman, Linköping University, Sweden
Correspondent: Click to Email
Nanocomposites from the Ti-Si-C system are of growing interest as a multifunctional coating material in electrical and tribological applications. We have previously demonstrated beneficial electrical contact properties and a ductile deformation behavior for Ti-Si-C nanocomposite thin films deposited by magnetron sputtering from a Ti@sub 3@SiC@sub 2@ compound target@footnote 1@ at substrate temperature below 300 °C.@footnote 2@ Here, we report on detailed characterization of the microstructure and surface conditions of Ti-Si-C nanocomposites. As evidenced by XRD, TEM, and XPS, the Ti-Si-C films consist of TiC nanocrystallites (<20 nm), embedded in a matrix of amorphous SiC with presence of graphitic carbon. The nc-TiC/a-SiC/g-C nanocomposite exhibited nanoindentation hardness and elastic-modulus values of 20 GPa and 290 GPa, respectively. The ductility of the material can be attributed to rotation and gliding of nc-TiC grains in the matrix. Furthermore, photoemission studies of as-deposited films on Si substrates show a native oxide thickness of 3-4 nm. The thermal stability of the coating was investigated by annealing in vacuum. Upon heating to 1000 °C, the oxide layer is removed and large amounts of free surface carbon appear, as well as surface silicon. This can be interpreted as C and Si segregation during the annealing. @FootnoteText@ @footnote 1@Maxthal, courtesy of Kanthal AB@footnote 2@P. Eklund et al J. Vac. Sci. Technol. B 23(6) 2486 (2005).