AlN micromechanical radial-contour disc resonator

Wang, Gang; Xu, Lixin; Ababneh, A.; Schwarz, Patrick; Feili, Dara; Seidel, H.

doi:10.1088/0960-1317/23/9/095002

Cited by 9 publications

(2 citation statements)

References 32 publications

(44 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The measured resonance frequencies of the device are very close to the estimated ones based on vibration theory and FEM modal analysis results. We achieved a Q‐factor of up to 15 650, which is high enough to guarantee high sensitivity of the sensor system and is comparable to that of other available disk resonators [6, 7] that require more complicated fabrication processes. We believe that this device can be deployed in a variety of mass detection sensors owing to its high performance and low fabrication cost.…”

Section: Resultsmentioning

confidence: 67%

Design and fabrication of cost‐effective side‐stem micromechanical disk resonator with large capacitive gap

2014

View full text Add to dashboard Cite

A high-performance micromechanical disk resonator is developed for use in mass detection biosensors. The resonator is designed to facilitate easy and cost-effective fabrication by anchoring the disk on the side stems and increasing the capacitive gap size up to 4.75 µm. The designed disk resonator operates in an elliptic contour-mode at a resonance frequency of 5.971 MHz with a quality factor of 4272 in ambient air condition and 17 221 in a 600 Torr vacuum environment.Introduction: With interest in sensing and frequency filtering applications increasing, disk resonators that vibrate in an in-plane mode are highly promising. In these resonators, the air damping effect is significantly reduced and a relatively high quality factor (Q-factor) can be achieved in ambient air conditions. However, two key issues encountered in the fabrication of the disk resonator are the gap size between the disk and electrodes and the alignment of each part inside the resonator [1]. It is well known that narrowing the gap size requires much more complicated and expensive fabrication processes. Hao et al. developed a disk resonator with an ultra-narrow capacitive gap of the order of 100 nm by employing a complex HARPSS [2] process that required six lithography steps in total and a number of etching and deposition steps for wireless applications [3]. In the work reported in this Letter, we designed and fabricated a disk resonator with a large gap between the disk and electrodes and investigated its resonance behaviour. We confirmed that the high Q-factor achieved with low production costs makes the fabricated disk resonator suitable for biosensor applications.

show abstract

Section: Resultsmentioning

confidence: 67%

Design and fabrication of cost‐effective side‐stem micromechanical disk resonator with large capacitive gap

2014

View full text Add to dashboard Cite

show abstract

“…PZT is one of the most widely used piezoelectric materials, LiNbO 3 has a high electromechanical coupling coefficient, and ZnO and AlN each have significant advantages in terms of their compatibility with IC technology [ 12 , 13 , 14 ]. Among these four materials, AlN has the highest acoustic wave velocity and excellent thermal conductivity [ 15 , 16 ]. Therefore, various AlN-based resonators have been reported, such as flexural mode resonators [ 17 ], film bulk acoustic wave resonators (FBAR) [ 18 ], contour mode resonators [ 19 ], and lamb wave resonators [ 20 ].…”

Section: Introductionmentioning

confidence: 99%

Temperature Characteristics of a Contour Mode MEMS AlN Piezoelectric Ring Resonator on SOI Substrate

Fei

Ren

2021

Micromachines

View full text Add to dashboard Cite

As a result of their IC compatibility, high acoustic velocity, and high thermal conductivity, aluminum nitride (AlN) resonators have been studied extensively over the past two decades, and widely implemented for radio frequency (RF) and sensing applications. However, the temperature coefficient of frequency (TCF) of AlN is −25 ppm/°C, which is high and limits its RF and sensing application. In contrast, the TCF of heavily doped silicon is significantly lower than the TCF of AlN. As a result, this study uses an AlN contour mode ring type resonator with heavily doped silicon as its bottom electrode in order to reduce the TCF of an AlN resonator. A simple microfabrication process based on Silicon-on-Insulator (SOI) is presented. A thickness ratio of 20:1 was chosen for the silicon bottom electrode to the AlN layer in order to make the TCF of the resonator mainly dependent upon heavily doped silicon. A cryogenic cooling test down to 77 K and heating test up to 400 K showed that the resonant frequency of the AlN resonator changed linearly with temperature change; the TCF was shown to be −9.1 ppm/°C. The temperature hysteresis characteristic of the resonator was also measured, and the AlN resonator showed excellent temperature stability. The quality factor versus temperature characteristic was also studied between 77 K and 400 K. It was found that lower temperature resulted in a higher quality factor, and the quality factor increased by 56.43%, from 1291.4 at 300 K to 2020.2 at 77 K.

show abstract