Reactive-sputter-deposited TiN films on glass substrates

The effects of strain energy on the preferred orientation of TiN thin films were investigated. In the TiN film deposited by plasma‐enhanced chemical‐vapor deposition with a power of 50 W, the overall energy of the film mainly depended on the surface energy because its strain energy was relatively small. The preferred orientation of the film corresponded to the plane with the lowest surface energy, i.e., (200). However, in the TiN film deposited by rf sputtering with a power of 200 W, the overall energy of the film was largely controlled by strain energy due to its large strain energy, and its growth orientation corresponded to the plane with the lowest strain energy, i.e., (111). Furthermore, the preferred orientation of the TiN film was changed from (200) to (111) with the film thickness. It is considered that this phenomenon is due to the increase of strain energy with its thickness.

Effects of strain energy on the preferred orientation of TiN thin films

Design of a Ti/TiC/DLC functionally gradient coating based on studies of structural transitions in Ti–C thin films

Although single-layer coatings are finding a range of applications in many sectors of engineering, there are an increasing number of applications where the properties of a single material are not sufficient. One way to surmount this problem is to use a multilayer coating that combines the attractive properties of several materials, each chosen to solve a problem in the application. Simple examples of this include the use of interfacial bonding layers to promote adhesion, or thin inert coatings on top of wear-resistant layers to reduce the corrosion of cutting tools. There is, however, mounting evidence that the multilayer structure produced when many alternating layers of two materials are deposited can lead to improvements in performance over a mixed coating (by virtue of the introduction of new interfaces) even if the two materials do not have specific functional requirements in the intended application. In this paper results for multilayer coatings in the TiN system will be presented showing the advantages of compositionally and structurally modulated coatings over conventional single-layer titanium nitride coatings in tribological applications. The results will be discussed in light of the microstructure and properties of the coatings produced by the two different multilayer coating techniques.

Multilayer coatings for improved performance

ScN layers, 345 nm thick, were grown on MgO(001) substrates at 750 °C by ultrahigh-vacuum reactive magnetron sputter deposition in pure N2 discharges at 5 mTorr. The N2+ to Sc ratio incident at the substrate and growing film was maintained constant at 14, while the ion energy EN2+ was varied from 13 to 50 eV. All films were stoichiometric with N/Sc ratios of 1.00±0.02. However, microstructural and surface morphological evolution were found to depend strongly on EN2+. The nucleation and initial growth stages of ScN films deposited with EN2+=13 eV are dominated by the formation of 111- and 002-oriented islands, but preferred orientation rapidly evolves toward a purely 111 texture by a film thickness of ≃50 nm as 002 grains grow out of existence in a kinetically limited competitive growth mode. In distinct contrast, films deposited with EN2+=20 eV grow in a cube-on-cube epitaxial relationship with the substrate and exhibit no indication of 111-oriented grains, even in the earliest stages. Increasing EN2+ to ...

Growth of poly- and single-crystal ScN on MgO(001): Role of low-energy N2+ irradiation in determining texture, microstructure evolution, and mechanical properties

P.J. Burnett

Papers

Correlation of process and system parameters with structure and properties of physically vapour- deposited hard coatings