Oscillator far-from-carrier phase noise reduction via nano-scale gap tuning of micromechanical resonators
Journal
TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems
Pages
798-801
Date Issued
2009
Author(s)
Akgul, M.
Kim, B.
Hung, L.-W.
Lin, Y.
Li, W.-C.
Huang, W.-L.
Gurin, I.
Borna, A.
Nguyen, C.T.-C.
Abstract
Substantial improvements in the far-from-carrier phase noise of oscillators referenced to stand-alone (as opposed to arrayed) capacitively transduced micromechanical disk resonators have been attained via the use of atomic layer deposition (ALD) to tune the electrode-to-resonator capacitive gaps. Specifically, ALD of about 30 nm of hafnia (HfO 2 ) onto the surface of a released 60-MHz micromechanical disk resonator to reduce its effective resonator-to electrode gap size from 92 nm to 32 nm provides an increase in power handling leading to more than 15-20 dB reduction in the far-from-carrier phase noise of an oscillator referenced to this resonator. This ALD-enabled nano-scale gap tuning provides a simple and effective method to satisfy increasing demands for higher short-term stability in frequency references for electronic applications.
SDGs
Type
conference paper