Stress corrosion of organosilicate glass films in aqueous environments: Role of pH

Subcritical cracking of thin glass films caused by stress-corrosion phenomena cannot be neglected when it comes to application and manufacturing processes that involve exposure to aqueous environments. A protocol is introduced to allow for a quantitative study of stress corrosion through channel cracking experiments. By this method, an exponential dependence of the crack propagation rate on the pH of the aqueous environment is revealed. Therefore, this behavior should be accounted for through the use of an appropriate pre-exponential factor in the expression of channel cracking rate. This factor should reflect the reduced crack resistance of the glass film caused by the weakening of the silica bonds behind the crack tip in the aqueous environment. A direct comparison between commercial slurries and reference solutions confirms that the crack resistance is a function of the pH of the ambient.