Due to their high specific energy and energy density, micro-solid oxide fuel cells1,2 (µ-SOFCs) are seen as one of the technologies that could help satisfying the continuously increasing demand for electric energy in portable electronic devices. The µ-SOFC is a less than 1 µm thin free-standing membrane. The membrane consists of ceramic and metallic thin film layers integrated on a micro-structurable substrate based on MEMS technologies. In this study, Foturan® glass ceramic and silicon µ-SOFCs substrates are compared in terms of etching behavior, mechanical and thermomechanical properties