Lattice defects in lithium tantalate

Author

Doukhan, J.C. ; Cordier, P. ; Doukhan, N. ; Fragneau, M. ; Aubry, J.P.

Author_Institution

Lab. de Structure et Proprietes de l´´Etat Solide, Univ. de Lille Flandres Artois, Villeneuve d´´Ascq, France

fYear

1989

fDate

31 May-2 Jun 1989

Firstpage

497

Lastpage

508

Abstract

Lattice defects in lithium tantalate single crystals and their possible effect on the performances of piezoelectric devices are investigated. These defects have been characterized by various techniques and especially by transmission electron microscopy (TEM). It is found that the density of as-grown defects should not induce any appreciable decrease of the piezoelectric performance except for some dislocations that generate nonremovable ferroelectric domains around them. Such dislocations can also be accidentally introduced by matching operations; in this case their density can be much larger and an appreciable decrease of the piezoelectric performances may result. The techniques used for sawing and polishing are thus very important for getting high-performance devices

Keywords

crystal defects; crystal resonators; lithium compounds; transmission electron microscope examination of materials; LiTaO₃ crystals; TEM; as-grown defects; dislocations; high-performance devices; induced defects; lattice defects; matching operations; nonremovable ferroelectric domains; piezoelectric devices; piezoelectric performance; polishing techniques; sawing techniques; transmission electron microscopy; Cooling; Crystalline materials; Crystals; Ferroelectric materials; Lattices; Lithium compounds; Machining; Sawing; Temperature; Toxicology;

fLanguage

English

Publisher

ieee

Conference_Titel

Frequency Control, 1989., Proceedings of the 43rd Annual Symposium on

Conference_Location

Denver, CO

Type

conf

DOI

10.1109/FREQ.1989.68909

Filename

68909