European Workshop on Piezoelectric Materials : Crystal Growth, Properties and Prospects

J. Phys. IV France 04 (1994) C2-195-C2-198
DOI: 10.1051/jp4:1994224

(0001) quartz surface imperfections

F. BART^{1, 2}, M. GAUTIER¹, F. JOLLET¹ and J.P. DURAUD<sup>3

1</sup>  Service de Recherches sur les Surfaces et l'Irradiation de la Matière, CEA Centre d'Etudes de Saclay, Direction des Sciences de la Matière, Département de Recherches sur l'Etat Condensé, Atomes et Molécules, 91191 Gif-sur-Yvette, France
²  Fisons Instruments, 94110 Arcueil, France
³  Laboratoire Pierre Süe, C.E.A. C.N.R.S., Direction des Sciences de la Matière, Département de Recherches sur l'Etat Condensé, Atomes et Molécules, 91191 Gif-sur-Yvette, France

Abstract
Monocrystalline (0001) quartz surfaces may present two kinds of imperfections : point defects (surface oxygen vacancies) and tridimensional disorder (superficial amorphization). The point defects are studied thanks to Refection Electron Energy Loss Spectroscopy experiments, which show that electronic transitions (5.1 and 7.2 eV) associated with surface oxygen vacancies appear in the gap of α-quartz under ion or electron bombardment and 900°C vacuum heating. The defects responsible for these structures are located in the first nm under the surface. X-ray Absorption Near Edge experiments (XANES) at the O K-edge show that the 900°C vacuum heating leads moreover to the destruction of the surface crystallinity (≈5nm), as proved by the modification of the multiple scattering structures.

© EDP Sciences 1994