PROJECT TITLE :

Quality Factor in Polycrystalline Diamond Micromechanical Flexural Resonators

ABSTRACT:

This paper reports an investigation into the numerous dissipation mechanisms which will affect polycrystalline diamond micromechanical resonators. Double-ended tuning fork and cantilever resonators were fabricated from 1–5- $mu textm$ thick microcrystalline diamond films. It's shown that the standard factor of the low frequency (<500 kHz) resonators is restricted by surface loss, whereas the thermoelastic damping limits the standard factor of the upper frequency resonators. In resonators where surface loss is that the dominant effect, the dependence of quality issue on resonator thickness is demonstrated. The addition of a lossy surface layer of Al2O3 deposited via atomic layer deposition is shown to degrade quality issue, and an experiment that any demonstrates the effect of surface dissipation and leads to a discount in quality factor that scales with the thickness of the Al2O3 layer. Heat treatment of cantilever resonators in N2 for various times up to 660 min is used to switch the resonator surface and is shown to lead to a threefold increase in quality factor up to 365 000 at 26.vi kHz. [2015-0094]