Stress variation with temperature/time and its correlation to film structure and deposition parameters

Abstract

This study focused on measuring the stress of TiN films prepared by rapid thermal processing, by sputtering, and by furnace annealing. Also included in the study were W and Al alloy films. The stress measurements were done at room temperature, and then further data were collected with temperature up to 870 °C for W and TiN. Al alloy films were temperature cycled up to 500 °C. Film structure was studied by transmission electron microscopy (TEM) analysis prior to and just after thermal cycling. Hysteresis curves were obtained for all films. Graphical stress temperature correlations were made for films of different thicknesses. TEM results of TiN films prepared by rapid thermal processing, furnace annealing, and sputter deposition, indicated a reduction in grain size along with an increase in the tensile stress upon completion of thermal cycling of the films.

Stress reduction in sputter deposited films using nanostructured compliant layers by high working-gas pressures

“…This is partially due to adsorbed oxygen in the voids, which results in an increase of stress to compressive. 14 Similarly, the stress is a sensitive function of dc bias voltage 11 and substrate temperature 14,17 near the transition between tensile and compressive values, which makes the stress control difficult. A rf-substrate biasing technique has been shown to improve the stress control over an optimum regime of cathode current, pressure, and the rf-substrate bias values.…”

Stress reduction in tungsten films using nanostructured compliant layers

“…In addition, the stress of these films evolves in time partially due to adsorbed oxygen in the voids, which leads to compressive stresses. 11 Similarly, the stress is a sensitive function of the dc bias voltage 8 and substrate temperature 11,18 near the transition be-tween tensile and compressive values. Again this makes stress control difficult when low tensile or compressive values are desired.…”

Microstructural characterisation of tungsten coatings deposited using plasma sputtering on Si substrates

“…interface. Several methods such as rf-substrate biasing [9] and substrate temperature [10] techniques have been proposed to reduce the intrinsic stress of coatings. In the present work, we present the structural and morphological properties evaluated by atomic force microscopy, X-ray diffraction and scanning electron microscopy-energy dispersive spectrometry of W thin films deposited by an RF Plasma system in diode configuration [11] with microstructure in multilayer as a function of the pressure and sputter gas.…”