Quartz Resonator & Oscillator Tutorial


	BVA resonators are designed primarily to minimize stresses due to the mounting structure and the instabilities due to the electrodes (see “Stresses on a Quartz Resonator Plate” and subsequent pages in the next chapter). The BVA₂ structure shown above consists of three quartz plates of the same angles of cut and azimuthal orientation. The resonator plate is the plate “C” in the center. The active part of plate C is separated from the outer inactive part near the edges by means of cutouts, and the active area is connected to the inactive area by means of small quartz bridges. The outside plates D1 and D2 contact the C plate only outside the cutouts. The electrodes, deposited onto the center areas of D1 and D2, are separated from the active area of the resonator by means of small, 5m to 50 m, gaps.
	The best resonator short term stability measurements reported to date have been obtained with BVA resonators, i.e., s_y(t) of parts in 10¹⁴ at the flicker floor (see chapter 4).


	R. J. Besson, “A New ‘Electrodeless’ Resonator Design,” Proc. 31st Ann. Symp. on Frequency Control,” pp. 147-152, 1977

	R. J. Besson, J-J Boy, M. M. Maurey, “BVA Resonators and Oscillators: A Review. Relation with Space Requirements and Quartz Material Characterization,” Proc. 1995 IEEE Int’l Frequency Control Symposium, pp. 590-599, 1995