Thermoelastic damping in a mems resonator pdf

T he thermoelastic damping as we ll as frequ en cy of the structure of. An investigation on thermoelastic damping of highq ring. A finite element analysis of thermoelastic damping in. For vacuum encapsulated devices, thermoelastic damping ted and support loss are the most important damping mechanism in mems resonators. Mems motivation simple 1d model unbounded domain approximation pml and resonance. Investigation of energy dissipation in low frequency vibratory. The effect of thermoelastic damping on the total qfactor of. Pdf damping effects are very important in memsbased sensors and actuators.

The vent width plays a more important role than the vent length. The physical parameters of single crystal silicon beam used for simulation are shown in table 1. Design strategies for controlling damping in micromechanical and. Geometric effects on thermoelastic damping in mems resonators. Thermoelastic damping, which arises when you subject a material to cyclic stress, is an important factor when designing mems resonators.

Geometric effects on thermoelastic damping in mems resonators y. Coventorware tutorial university of california, berkeley. This paper considers ring resonator based rate sensors and investigates the influence of design changes to the ring and support legs on thermoelastic damping, which is the dominant dissipation mechanism. Entropy generation and thermoelastic damping in the in. Thermoelastic damping effect analysis in micro flexural resonator of. Intuitive for mems engineer 3d model construction from gdsii files streamlined operation for common mems simulations, including. Bindel computer science division department of eecs. One of the major dissipation mechanisms is thermoelastic damping ted that needs an accurate consideration for prediction. The known sources of energy loss in micromechanical beam resonators are air damp ing, acoustic loss through the anchor, thermoelastic damping, and internal. Thermoelastic damping and support loss in mems ring. Thus, due to the resulting heat flux, energy is lost to bring about this damping. Direct detection of akhiezer damping in a silicon mems resonator. This thesis focuses on understanding and quantifying the effects of thermoelastic damping and support loss on the damping performance of. Vents reduce the structural rigidity and thus reduce the resonant frequency.

We examined the most important mechanisms that are believed to limit the quality factor in mems tuning fork resonators i. In this paper, the governing equations of coupled thermoelastic problems are established based on the generalized thermoelastic theory with one relaxation time. Thermoelastic damping in resonators is studied using the finite element method. In this paper, the quality factor of the resonator is computed by. Thermoelastic damping is one of the most important energy loss mechanisms in mems resonators especially when the resonator is miniaturized to achieve higher frequencies. Microrings are a common resonator of mems a microelectromechanical system, which are widely applied to mems sensors and actuators 14. Pdf damping effects in mems resonators researchgate. Pullin, electrostatic spring softening coupled thermomechanical ex. Engineering mems resonators with low thermoelastic damping. For applications requiring high performance angular rate measurements it is important to be able to design mems rate sensors with high quality factors q. Mems a frequencyselective device that would later become known as the resonant gate tran sistor see fig. Eigenvalues, resonance poles, and damping in mems d. This tiny, bulkfabricated device, measuring less than 110th of an inch.

Modeling of thermoelastic damping in mems resonators. A finite element analysis of thermoelastic damping in vented mems. Vents at the clamped end can raise the quality factor significantly. Thermoelastic damping in microbeam resonators sciencedirect. Yi department of mechanical and materials engineering, university of denver, denver, co 80208, usa received 25 august 2006. Request pdf engineering mems resonators with low thermoelastic damping this paper presents two approaches to analyzing and calculating thermoelastic damping in micromechanical resonators. Direct detection of akhiezer damping in a silicon mems. It has been verified that thermoelastic damping is a significant loss mechanism near room temperature in mems resonators.