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Materials Research

Print version ISSN 1516-1439

Abstract

GUZZO, Pedro Luiz et al. Characterization of growth sectors in synthetic quartz grown from cylindrical seeds parallel to [0001] direction. Mat. Res. [online]. 2004, vol.7, n.2, pp. 285-291. ISSN 1516-1439.  http://dx.doi.org/10.1590/S1516-14392004000200011.

In the present study, the morphology and the impurity distribution were investigated in growth sectors formed around the [0001] axis of synthetic quartz crystals. Plates containing cylindrical holes and cylindrical bars parallel to [0001] were prepared by ultrasonic machining and further used as seed-crystals. The hydrothermal growth of synthetic quartz was carried out in a commercial autoclave under NaOH solution during 50 days. The morphologies of crystals grown from cylindrical seeds were characterized by X-ray diffraction topography. For both types of crystals, +X- and X- growth sectors were distinctly observed. Infrared spectroscopy and ionizing radiation were adopted to reveal the distribution of point defects related to Si-Al substitution and OH-species. It was found a different distribution of Al-related centers in relation to the crystals grown from conventional Y-bar and Z-plate seeds.

Keywords : synthetic quartz; impurity segregation; infrared spectroscopy; X-ray topography.

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