Achieving 1 Million Quality Factor in Fused Silica Planar Frame Resonator (PFR)

This letter reports the quality factor (
$Q$
-factor) of a fused silica planar frame resonator (PFR). The PFR is an axisymmetric structure composed of a beam head, a bridge, two wings, two longitudinal beams, and a supporting tail. Fused silica PFR with a 6 mm beam length is chemically etched from a 500-
$\mu \text{m}$
-thick silica glass wafer. The resonant frequency of the flexural mode is measured to be 9654 Hz and the
$Q$
-factor as high as 1.13 million is acquired by the ringdown method. The
$Q$
-factor of the PFR has the potential for further improvement with structural design and fabrication optimization.