MACROSEGREGATION DURING BRIDGMAN GROWTH OF GE1-XSIX MIXED-CRYSTALS

被引：16

作者：

HELMERS, L

SCHILZ, J

BAHR, G

KAYSSER, WA

机构：

[1] Institut für Werkstoff-Forschung, Deutsche Forschungsanstalt für Luft- und Raumfahrt (DLR)

来源：

JOURNAL OF CRYSTAL GROWTH | 1995年 / 154卷 / 1-2期

关键词：

D O I：

10.1016/0022-0248(95)00138-7

中图分类号：

O7 [晶体学];

学科分类号：

0702 ; 070205 ; 0703 ; 080501 ;

摘要：

We investigated the Bridgman growth of non-dilute Ge1-xSix mixed crystals and report on four samples of different composition. They are characterized by metallography and composition analysis. The macroscopic axial concentration profile is close to that of a completely mixed melt. The hydrodynamical origin of this strong stirring is discussed. Fluctuations of growth rate and/or composition result in strong striation patterns. The spacing bf the striae is found to be similar for all melt volumes, compositions and thermal environments used in our experiments, The crystal quality is generally poor. All samples show a grain structure. If the seed is of higher Si content than the first part of the grown crystal, formation of grains is considerably reduced. A model for understanding this finding is proposed.

引用

页码：60 / 67

页数：8

共 32 条

[1] INSTABILITY OF STEADY NATURAL-CONVECTION IN A VERTICAL FLUID LAYER [J].