Title :
Laterally driven polysilicon resonant microstructures
Author :
Tang, William C. ; Nguyen, Tu-Cuong H. ; Howe, Roger T.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., California Univ., Berkeley, CA, USA
Abstract :
Interdigitated finger (comb) structures are demonstrated to be effective for electrostatically exciting the resonance of polysilicon microstructures parallel to the plane of the substrate. Linear plates suspended by a folded-cantilever truss and torsional plates suspended by spiral and serpentine springs are fabricated from a 2-μm-thick phosphorus-doped low-pressure chemical vapor deposited polysilicon film. Resonance is observed visually, with frequencies ranging from 18 kHz to 80 kHz and quality factors from 20 to 130. Simple beam theory is adequate for calculating the resonant frequencies, using a Young´s modulus of 140 GPa and neglecting residual strain in the released structures
Keywords :
crystal resonators; electrostatic devices; elemental semiconductors; silicon; 18 to 80 kHz; 2 micron; LPCVD films; Q-factor; Young´s modulus; beam theory; comb structures; electrostatic excitation; folded-cantilever truss; interdigitated finger structures; laterally driven resonant microstructures; polycrystalline Si:P; quality factors; resonant frequencies; serpentine springs; spiral springs; torsional plates; Capacitive sensors; Chemicals; Fingers; Microstructure; Q factor; Resonance; Resonant frequency; Spirals; Springs; Substrates;
Conference_Titel :
Micro Electro Mechanical Systems, 1989, Proceedings, An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots. IEEE
Conference_Location :
Salt Lake City, UT
DOI :
10.1109/MEMSYS.1989.77961
