Title :
A piezoresistive CMOS-MEMS resonator with high Q and low TCf
Author :
Cheng-Syun Li ; Ming-Huang Li ; Chi-Hang Chin ; Chao-Yu Chen ; Sheng-Shian Li ; Feng, Philip X.-L
Author_Institution :
Inst. of NanoEngineering & Microsyst., Nat. Tsing Hua Univ., Hsinchu, Taiwan
Abstract :
A high-frequency CMOS-MEMS bulk-mode resonator via a differentially piezoresistive transduction was proposed in this work, demonstrating quality factor (Q) greater than 15,000, temperature coefficient of frequency (TCf) around -12.5ppm/°C, and operating power lower than 400μW, all in a single device. To attain the highest Q among reported CMOS-MEMS resonators to date, a dog-bone design was adopted with its two oxide-rich longitudinally vibrating beams which consist of only low-loss materials (i.e., poly-Si and SiO2) from a standard 0.35μm 2-poly-4-metal (2P4M) CMOS technology. To achieve such decent temperature stability, a constant-resistance control approach was implemented to enable an ovenized element where the poly-Si heater and thermometer are both embedded inside the resonator structure, hence providing excellent thermal isolation, localized heating capability, and on-site/real-time temperature measurement.
Keywords :
CMOS integrated circuits; Q-factor; micromechanical resonators; piezoresistive devices; temperature measurement; thermal stability; thermometers; 2-poly-4-metal CMOS technology; constant-resistance control; differentially piezoresistive transduction; dog-bone design; high-frequency CMOS-MEMS bulk-mode resonator; localized heating capability; on-site/real-time temperature measurement; oxide-rich longitudinally vibrating beams; piezoresistive CMOS-MEMS resonator; poly-Si heater; quality factor; resonator structure; size 0.35 mum; temperature coefficient of frequency; temperature stability; thermal isolation; thermometer; CMOS integrated circuits; Electrodes; Heating; Materials; Metals; Piezoresistance; Thermal stability; CMOS-MEMS; High Q; Oven; Piezoresistive; Resonator; Temperature Compensation; Thermal Stability;
Conference_Titel :
European Frequency and Time Forum & International Frequency Control Symposium (EFTF/IFC), 2013 Joint
Conference_Location :
Prague
DOI :
10.1109/EFTF-IFC.2013.6702247