Interface demarcation in Bridgman-Stockbarger crystal growth of II-VI compounds

Donald C. Gillies; Sandor L. Lehoczky; Frank R. Szofran; Ching-Hua Su; David J. Larson Jr.

doi:10.1117/12.46501

1 August 1991 Interface demarcation in Bridgman-Stockbarger crystal growth of II-VI compounds

Donald C. Gillies, Sandor L. Lehoczky, Frank R. Szofran, Ching-Hua Su, David J. Larson Jr.

Proceedings Volume 1484, Growth and Characterization of Materials for Infrared Detectors and Nonlinear Optical Switches; (1991) https://doi.org/10.1117/12.46501
Event: Orlando '91, 1991, Orlando, FL, United States

Abstract

NASA has considerable interest in the growth of strategically important materials in microgravity. Bridgman-Stockbarger directional solidification within a sealed ampoule are planned for CdZnTe, HgCdTe, HgZnTe and GaAs. In order to optimize the thermal parameters for the growth conditions, it is necessary to characterize the furnace and understand its behavior. This entails the use of appropriate thermal modelling based on the known physical properties of the material, the ampoule material and the furnace itself. A suitable test is the determination of the shape and location of the solid-liquid interface relative to the furnace. Electrical and chemical etching techniques have been used to locate this interface for certain materials. One of these, germanium doped with gallium, a material with well-known properties, has been used to characterize the furnace model. Demarcation has been extended to cadmium telluride by post-growth examination of the precipitation of tellurium inclusions at positions of abrupt thermal changes in the furnace regime. Deliberately imposed mechanical vibration of the melt can also produce evidence of interface location. This work was done with infrared microscopy. Other techniques, available in termary solid solutions, involve the effect of change of lower zone furnace temperatures on the compositional profile. Examples of demarcation are shown in gallium-doped germanium, cadmium telluride, and mercury zinc telluride.

Citation Download Citation

Donald C. Gillies, Sandor L. Lehoczky, Frank R. Szofran, Ching-Hua Su, and David J. Larson Jr. "Interface demarcation in Bridgman-Stockbarger crystal growth of II-VI compounds", Proc. SPIE 1484, Growth and Characterization of Materials for Infrared Detectors and Nonlinear Optical Switches, (1 August 1991); https://doi.org/10.1117/12.46501

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available