In a microgravity environment obtainable in an orbiting space shuttle, it is possible to virtually eliminate gravity related effects such as buoyancy driven convection and hydrostatic forces thus providing an ideal environment for diffusion-controlled, containerless crystal growth processes. Studies of CdZnTe boules grown on space shuttle mission USML-1 revealed that regions of the boules grown with wall contact were associated with a higher defect density than regions grown with partial or no wall contact. Defect densities in certain regions grown without wall contact were as low as 5x102/cm2 to 1.2x103/cm2. More detailed studies on the effects of wall contact were sought in the USML-2 mission. Two CdZnTe boules (GCRC-1 and GCRC-2) were grown by the seeded Bridgman-Stockbarger method. Boule GCRC-1 was grown under constrained conditions to force full wall contact while boule GCRC-2 had a tapered geometry designed to minimize wall contact. Defect distributions in the boules were investigated by synchrotron white beam x-ray topography. Results clearly verify that ampoule wall contact plays an important role in determining the incidence of crystal imperfections.
Effect of constrained growth on defect structures in microgravity grown CdZnTe boules
CdZnTe-Wachstum in der Schwerelosigkeit und der Einfluß auf Störstellenstrukturen
Journal of Electronic Materials ; 27 , 6 ; 556-563
1998
8 Seiten, 7 Bilder, 1 Tabelle, 29 Quellen
Article (Journal)
English
Online Contents | 2012
Some Basic Phenomena of Water Boules
British Library Conference Proceedings | 2000
|Sport - Boules - Ça roule pour l'Île-de-France
Online Contents | 2011
Polished homogeneity testing of Corning fused silica boules [3782-60]
British Library Conference Proceedings | 1999
|