Instabilities in thin films on hyperelastic substrates by 3D finite elements

Channel cracking in thin films on substrates of finite thickness

Solutions are presented for the elastic plane-strain problem of a crack in a coating on a compliant substrate of finite thickness. Analysis of the problem shows that substrate thickness has a significant effect on the steady-state energy release rate for channel cracks. This is so over a wide range of elastic mismatch between film and substrate, but is especially important if the substrate is m...

Electrohydrodynamic Instabilities in Thin Polymer Films

Nanocrystalline silicon thin films on PEN substrates

We study the structural and electrical properties of intrinsic layers growth close to the transition between amorphous silicon (a-Si:H) and nanocrystalline silicon (nc-Si:H) deposited on glass and PEN without intentional heating. These samples showed different behaviour in Raman shift and XRD spectra when compared with that of samples deposited at 200oC. Electrical properties of these films als...

Profilometry of thin films on rough substrates by Raman spectroscopy

Thin, light-absorbing films attenuate the Raman signal of underlying substrates. In this article, we exploit this phenomenon to develop a contactless thickness profiling method for thin films deposited on rough substrates. We demonstrate this technique by probing profiles of thin amorphous silicon stripes deposited on rough crystalline silicon surfaces, which is a structure exploited in high-ef...

Instabilities in the flow of thin films on heterogeneous surfaces

We present computational and experimental results involving instability development in the gravity-driven flow of thin fluid films on heterogeneous surfaces, with particular emphasis on the dynamics of the fluid fronts. We show that heterogeneity of the solid surface can have a significant effect on the flow dynamics. Since the effect of heterogeneity often competes with the basic instability m...