Title :
A very low profile, shock-resistant, surface-mountable quartz crystal unit
Author :
Smythe, R.C. ; Greenstein, J. ; Lipeles, J.
Author_Institution :
Piezo Technol. Inc., Orlando, FL, USA
Abstract :
A very low profile, surface-mountable quartz crystal unit capable of withstanding shock levels of 100000 Gs or more has been developed. An AT-cut, 33 MHz, 3rd overtone unit has overall dimensions of .31 in (7.9 mm) diameter and 0.05 in (1.3 mm) maximum height. The unit consists of a top cover, a resonator plate, and a bottom cover. All three pieces are made of identically oriented, polished and deep-etched, swept, premium- Q quartz. A finite-element model of the three-piece sandwich, constructed using both orthotropic and general-purpose anisotropic elements, allowed the unit to be designed to the high G level. To obtain the necessary material properties, measurements were made of the breaking strength of samples of the quartz used for a range of surface treatments. Bond shear strength and bond tensile strength were measured
Keywords :
crystal resonators; packaging; quartz; surface mount technology; 0.05 in; 0.31 in; 33 MHz; 3rd overtone unit; AT-cut; acceleration hardening; bond shear strength; bond tensile strength; bottom cover; breaking strength; deep etching; diameter; dimensions; finite-element model; height; low profile; premium-Q quartz; resonator plate; shock level 100000 g; shock-resistant; surface treatments; surface-mountable quartz crystal unit; three-piece sandwich; top cover; Acceleration; Bonding; Chemicals; Crystallization; Electric shock; Etching; Lakes; Metallization; Stress measurement; Weapons;
Conference_Titel :
Frequency Control, 1991., Proceedings of the 45th Annual Symposium on
Conference_Location :
Los Angeles, CA
Print_ISBN :
0-87942-658-6
DOI :
10.1109/FREQ.1991.145892
