High Q, precision SC cut resonators with low acceleration sensitivity

Abstract

A new mounting structure has enabled the construction of high Q resonators with very low acceleration sensitivity. Values in the range of mid parts in 10/sup 11/ to low parts in 10/sup 10/ per g have been achieved with a simple planar support structure. Utilizing a thin chemically etched lead-frame, a four-point mount with built in stress relief has been designed to mount in the plane of the resonator. The advantages of this structure include good symmetry, minimal residual manufacturing stresses, and minimal asymmetric vibratory stresses. Many different configurations have been designed and built using 8 and 10 mm 10 MHz 3/sup rd/ overtone SC cut plano-convex crystals with excellent results.