On-line version ISSN 1980-5373
GUZZO, Pedro Luiz et al. Characterization of growth sectors in synthetic quartz grown from cylindrical seeds parallel to  direction. Mat. Res. [online]. 2004, vol.7, n.2, pp. 285-291. ISSN 1980-5373. 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  axis of synthetic quartz crystals. Plates containing cylindrical holes and cylindrical bars parallel to  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.