Thermoelastic dissipation in etch-hole filled Lamé bulk-mode silicon microresonators

The perforation of a Lamé bulk-mode silicon mechanical resonator via uniformly distributed etch holes has been observed to drastically reduce the quality factor (Q) by over 90%. The cause of this sharp drop remains largely unknown. A high Q is important, while etch holes are commonly used in the fabrication of resonators. This letter traces the cause to thermoelastic dissipation through the use of finite-element analysis based on coupled thermoelastic equations. The results from the analysis are well corroborated by data from measurements of fabricated silicon-on-insulator devices. © 2012 IEEE.