A preliminary investigation of thermo-elastic damping in silicon rings

• Published in: Journal of micromechanics and microengineering 2004-09, Vol.14 (9), p.S108-S113
• Main Authors: Wong, S J, Fox, C H J, McWilliam, S, Fell, C P, Eley, R
• Format: Article
• Language: English
• Subjects: Applied sciences; Electronics; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; Microelectronic fabrication (materials and surfaces technology); Micromechanical devices and systems; Physics; Precision engineering, watch making; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/14/9/019

Zener's model for thermo-elastic loss, when applied to uniform beams undergoing flexural vibrations, gives theoretical predictions of mechanical Q-factor that often agree well with experimental measurements. The use of silicon ring resonators in MEMS devices is now becoming increasingly common. This paper considers the application of Zener's theory to thin, circular rings and presents a simple expression for the Q-factor associated with in-plane flexural modes of vibration. The theoretical predictions are shown to be in good agreement with experimental measurements for a practically relevant range of ring sizes. The relationships between ring dimensions, ambient temperature and Q-factor are explored.