Residual Stress and Surface Energy of Sputtered TiN Films

Abstract

Morphology, structure, residual stress, and surface energy of magnetron-sputtered titanium nitride (TiN) thin films, deposited at 300°C with a thickness in the 0.5-1.7 lm range, were characterized. Film microstructure, the origin of residual stress, and its effect on the surface energy were analyzed. The grain size increased with the film thickness. X-ray diffraction showed (200) to (111) preferred orientation transitions with the increasing film thickness. The stress in the TiN films changed from compressive 20.3 GPa to tensile with the film thickness reaching 0.3 GPa. Larger grain size, initial porosity, and sub-grains generation are the reasons for significant changes in the residual stress. Surface energy was investigated by contact angle of water and glycerol droplets, which both show a significant change with the different stress state and crystal preferred orientation. The TiN films form a contact angle larger than 100°with water as a test liquid, demonstrating their hydrophobicity. While the residual stress changes from compressive to tensile, the contact angle reaches 118°, and the corresponding surface energy changes from 38.8 to 24.2 mJ/ m 2 . One can expect to achieve a certain desired surface state of TiN films for potential applications.

Production Strategies of TiNx Coatings via Reactive High Power Impulse Magnetron Sputtering for Selective H2 Separation

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Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

“…Titanium and tungsten nitride ceramics: Titanium nitride (TiN) has a low electrical resistivity that is comparable to some metals, high stiffness (Young’s modulus of 427–590 GPa) and high hardness, high melting temperature (2930 °C), high corrosion resistance [ 140 ], and low surface energy [ 141 ] – all beneficial properties for NEM switch applications. TiN is also one of the materials used in almost all standard surface and bulk micromachining, thus available from routine CMOS production, and it can be integrated in existing devices.…”

Synthesis of TiB2-Ni3B nanocomposite coating by DC magnetron sputtering for corrosion-erosion protection

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