Characterization of the Bridgman crystal growth process by radiographic imaging

Archibald L. Fripp; W. J. Debnam; Glenn A. Woodell; Robert F. Berry; Richard T. Simchick; S. K. Sorokach; Patrick G. Barber

doi:10.1117/12.49602

1 December 1991 Characterization of the Bridgman crystal growth process by radiographic imaging

Archibald L. Fripp, W. J. Debnam, Glenn A. Woodell, Robert F. Berry, Richard T. Simchick, S. K. Sorokach, Patrick G. Barber

Author Affiliations +

Proceedings Volume 1557, Crystal Growth in Space and Related Optical Diagnostics; (1991) https://doi.org/10.1117/12.49602
Event: San Diego, '91, 1991, San Diego, CA, United States

Abstract

The normal characterization of a Bridgman crystal growth procedure is to note the ingot preparation, ampoule size and material, the ampoule translation rate, and the furnace zone temperatures. Even though these are important parameters which must be recorded and controlled they may not represent a sufficient set to produce repeatable growth results. One of the primary growth variables, the actual growth rate, is often ignored. Even though it is well recognized that the actual growth rate is not equal to the ampoule translation rate the difference is usually assumed small and the stochastic nature of the difference has not been previously reported. These variations between pull rate and growth rate are especially acute in unseeded growth subjected to deep supercooling. This paper discusses both elemental (Ge) and alloy (PbSnTe) crystal growth that is monitored, via radiography, to reveal both the interface position and shape in real time. Both seeded and unseeded growth are examined. The actual growth rate is shown to be a strong function of the degree of supercooling. Actual growth rates that exceed the pull rate by a factor of greater than two have been observed and the interface shape has been observed to change from concave to flat to convex during the growth.

Citation Download Citation

Archibald L. Fripp, W. J. Debnam, Glenn A. Woodell, Robert F. Berry, Richard T. Simchick, S. K. Sorokach, and Patrick G. Barber "Characterization of the Bridgman crystal growth process by radiographic imaging", Proc. SPIE 1557, Crystal Growth in Space and Related Optical Diagnostics, (1 December 1991); https://doi.org/10.1117/12.49602

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