Stress Evolution in Alkoxide-Derived Gel Coating Films on Firing

Abstract

Fundamental understanding on stress evolution is lacking for gel-derived coating films although it causes crack formation in films. Especially stress evolution occurring on gel film densification via heating is cruicial for macroscopic cracking that is often accompanied by delamination. In the present study, in situ stress measurement was conducted on alkoxide-derived thin films during heating in order to clarify the effect of various processing parameters on stress evolution. The parameters include water-to-alkoxide ratio, heating rate, chelating agents, organic polymers and CH₃Si(OC₂H₅)₄.