화학공학소재연구정보센터
Journal of Crystal Growth, Vol.229, No.1, 275-282, 2001
Characterization of synthetic quartz crystals grown from cylindrical seeds produced by ultrasonic machining
The potential of ultrasonic machining is investigated as a tool to produce seed crystals for hydrothermal growth of synthetic quartz with required surface finish and unconventional geometries. For this purpose, cylindrical seeds with 5, 10 and 18 mm diameter were obtained along the optic axis of a Z-bar using a conventional ultrasonic machining process with abrasive particles ranging from 6 to 50 mum. The topography of seed surfaces was characterized by surface profilometry and scanning electron microscopy. Later, synthetic crystals were grown in a standardized hydrothermal growth condition using NaOH solution. The characterization of as-grown crystals was performed by double-crystal Xray topography with Laue geometry. Based on X-ray topographic images, it was observed that the density of dislocations, nucleated at the early stage of the growth period, increases with increasing roughness of the seed-crystal surface.