Long-term frequency stability of silicon MEMS resonators is fundamentally limited by surface-driven degradation mechanisms, including corrosion, moisture adsorption, surface oxidation, and defect evolution. These processes progressively alter surface energy, mass, stiffness, and internal stress, leading to frequency drift, Q degradation, and reduced device lifetime. This work presents a corrosion-resistant encapsulation strategy that conformally coats silicon resonator surfaces with a chemically robust, high-hardness barrier layer engineered for long-term environmental stability. The resulting encapsulation exhibits enhanced hardness and low chemical reactivity, thereby mitigating corrosion pathways and minimizing surface-induced frequency drift. Systematic aging studies under accelerated humidity and temperature conditions demonstrate significant reduction in drift rate and improved Q stability compared to uncoated devices.
Project is currently funded by: Federal