Effect of deposition conditions on thermo-mechanical properties of free standing silicon-rich silicon nitride thin film

Using resonance and bulge techniques, the mechanical properties of free standing Si-rich SiNx membranes were precisely measured to evaluate the effect of deposition conditions on them over a narrow range of particular technological interest. Values of the elastic modulus, the residual stress and the thermal expansion coefficient were obtained. It was found that even small differences in gas composition in low pressure CVD deposition make substantial changes in residual stress and significant but much smaller changes in the elastic modulus.

Graphical abstractEven small differences in gas composition in low pressure CVD deposition make substantial changes in residual stress and significant but smaller changes in the elastic modulus and thermal expansion coefficient of silicon-rich silicon nitride thin films.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► An investigation on the mechanical properties of the SiNx thin film was performed. ► The elastic modulus linearly depends on SiCl2H2/NH3 gaseous ratio. ► Thermal expansion coefficient of the SiNx thin film for each SiCl2H2/NH3 gaseous ratio was obtained. ► The SiCl2H2/NH3 gaseous ratio has also an effect on the residual stress of each sample.