AVS 45th International Symposium
    Thin Films Division Monday Sessions
       Session TF-MoA

Paper TF-MoA2
Characterization of TiN/CN@sub x@ Multilayers Deposited by DC Magnetron Sputtering

Monday, November 2, 1998, 2:20 pm, Room 310

Session: Mechanical Properties of Thin Films
Presenter: M.M. Lacerda, Northwestern University
Authors: M.M. Lacerda, Northwestern University
Y.H. Chen, Northwestern University
W.C. Chan, University of Hong Kong, China
B. Zhou, Northwestern University
Y.W. Chung, Northwestern University
Correspondent: Click to Email
Titanium nitride (TiN) is commonly used in wear protection coatings due to its high hardness. However, it is well known that thick TiN films develop columnar structure and are subject to cohesive failure. In this work, we used CN@sub x@ thin films to interrupt the growing TiN before the columns could initiate. The samples have been deposited by DC unbalanced magnetron sputtering at low pressure (2.5 mTorr) using an argon-20% nitrogen mixture. We applied a substrate bias of -200 V to promote ion bombardment. The CN@sub x@ thickness was kept constant at 1.3 nm. X-ray diffraction (XRD) patterns obtained at low angles (2°@<=@2@theta@@<=@5°) showed good interface between layers. XRD patterns at higher angles showed strong TiN (111) texture. The mechanical properties of the multilayers have been studied as a function of the TiN/CN@sub x@ thickness ratio (t@sub r@). Nanoindentation of samples with t@sub r@ = 2.3 showed high hardness value as compared to TiN films deposited at the same conditions. The TiN/CN@sub x@ films are at least 2.5 times harder than TiN samples. Internal stress of the same samples was calculated by the substrate curvature. Results showed that multilayers have compressive stress up to 10 times lower than TiN films. Electron microscopy results of the microstructure of these multilayered coatings will be presented.