Low-Stress CMOS-Compatible Silicon Carbide Surface-Micromachining Technology-Part II: Beam Resonators for MEMS Above IC

• Published in: Journal of microelectromechanical systems Vol. 20; no. 3; pp. 730 - 744
• Main Authors: Nabki, F, Cicek, P-V, Dusatko, T A, El-Gamal, M N
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.06.2011; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustic beams; Applied sciences; Arrays; Beams (radiation); Design engineering; Electrodes; Electronics; Exact sciences and technology; Heating; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mechanical instruments, equipment and techniques; Microelectromechanical systems; microelectromechanical systems (MEMS); Microelectronic fabrication (materials and surfaces technology); Micromechanical devices; Micromechanical devices and systems; Micromechanical resonators; Physics; Quality factor; Residual stress; Resonant frequencies; Resonant frequency; resonator arrays; Resonators; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Silicon carbide; silicon carbide (SiC); surface micromachining; thermal tuning; Tuning; Elastic constants; Micromechanical resonators; Modal analysis; microelectromechanical systems (MEMS); Deformation modulus; thermal tuning; Experimental study; silicon carbide (SiC); Young modulus; Silicon carbide; resonator arrays; Quality factor; Complementary MOS technology; Resonance frequency; Insertion loss; Heating elements; Surface micromachining; Modelling; Microelectromechanical device; Low temperature
• ISSN: 1057-7157; 1941-0158
• DOI: 10.1109/JMEMS.2011.2115130

Microelectromechanical beam resonators and arrays are fabricated using a custom low-temperature complementary-metal-oxide-semiconductor-compatible silicon carbide microfabrication process, detailed in Part I of this paper. Theoretical aspects are presented with modal analysis and numerical methods. Measurements of the resonant frequency, the quality factor, the transmission, and the tuning characteristics are presented for different device types and dimensions. Trends are analyzed, and performance metrics dependences are investigated. A tuning method based on integrated heaters is introduced and tested, yielding a very desirable constant insertion-loss tuning and a wide tuning range. Quality factors of up to 1493 and resonant frequencies of up to 26.2 MHz are demonstrated. Both the Young's modulus and the residual stress of the SiC film are extracted (261 GPa and <; ±30 MPa, respectively), and favorably compare to values reported for polysilicon.