Stability of wafer level vacuum encapsulated micromechanical resonators is characterized. The resonators are etched of silicon-on-insulator (SOI) wafers using deep reactive ion etching (DRIE) and encapsulated with anodic bonding. Bulk acoustic wave (BAW) resonator show drift better than 0.1 ppm/month demonstrating that the stability requirements for a reference oscillator can be met with MEMS. The drift of flexural resonators range from 4 ppm/month to over 500 ppm/month depending on resonator anchoring. The large drift exhibited by some flexural resonator types is attributed to packaging related stresses demonstrated by the sample temperature–frequency coefficients differing from the bulk silicon value.
|Number of pages||6|
|Journal||Sensors and Actuators A: Physical|
|Publication status||Published - 2006|
|MoE publication type||A1 Journal article-refereed|
|Event||13th International Conference on Solid-State Sensors, Actuators and Microsystems, TRANSDUCERS '05 - Seoul, Korea, Republic of|
Duration: 5 Jun 2005 → 9 Jun 2005
- reference oscillator