Temperature Compensation and Performance Enhancement Techniques for Lamé Mode MEMS Resonators

Abstract

The importance of micromachined resonators continues to grow as they become increasingly prevalent in a wide range of applications, from wearable devices to more complex applications such as wireless communication and aerospace. As a result of this increased demand, academics and industry are developing oscillators with higher performance and stability while focusing on cost reduction. Although numerous resonator architectures and electrical circuits to drive the resonator have been studied for many years, the problem of producing a fully compensated resonator that operates independently of ambient temperature remains unsolved. This work presents an analytical model for predicting the performance of a Lamé resonator with varying rotation angles, and different structure varieties are proposed. The adaptability of the proposed analytical model is demonstrated, and the model’s versatility is experimentally validated by fabricating multiple resonator variants and analyzing their frequency responses and temperature behavior. Afterward, a novel Lamé mode electrostatic resonator employing a chevron-shaped thermal actuator is proposed, which decreases the transducer gap resulting in a reduced motional resistance and overcoming the micro-fabrication process limitation in the minimum spacing of the structural silicon layer. It is shown that combining the heaters and the resonator in a small area may result in frequency stability over temperature by applying the ovenization concept utilized in oscillators.

Date	22 Dec 2022
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	Frédéric Nabki (Supervisor)