Apodization technique for spurious mode suppression in AlN contour-mode resonators

作者：Giovannini Marco; Yazici Serkan; Kuo Nai Kuei; Piazza Gianluca^*

来源：Sensors and Actuators A: Physical , 2014, 206: 42-50.

DOI：10.1016/j.sna.2013.11.023

• Aluminum nitride
• Resonator
• MEMS
• Apodization
• Spurious modes

This paper reports on the application of apodization techniques to 900 MHz-1 GHz MEMS AlN Contour-Mode Resonators (CMRs [1-6]) to efficiently suppress spurious modes in close proximity of the main mechanical resonance. This concept has been applied with excellent results to a variety of one port resonators formed by patterned top electrodes made out of aluminum, and a floating bottom electrode made out of platinum sandwiching the AlN film. As also predicted by 3D COMSOL analysis, a complete elimination of the spurious responses (>90% suppression) is attained without significantly impacting the quality factor, Q, and electromechanical coupling coefficient, k(t)(2), of the device. On average, the Q improves except for resonators with thick (220 nm) top electrodes for which <11% degradation in Q is recorded. The k(t)(2) reduction is <20% and it has an absolute value >1% for all designs.

• 出版日期2014-2-1