Accession Number:

ADA455963

Title:

Vertical Gradient Freezing Using Submerged Heater Growth With Rotation and With Weak Magnetic and Electric Fields

Descriptive Note:

Journal article

Corporate Author:

NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF MECHANICAL AND AEROSPACE ENGINEERING

Personal Author(s):

• Bliss, D. F.
• Holmes, A. M.
• Wang, X.
• Ma, N.
• Iseler, G. W.

Report Date:

2005-04-18

Pagination or Media Count:

10.0

Abstract:

Investigations for the melt growth gallium-antimonide GaSb semiconductor crystals are underway at the US Air Force Research Laboratory at Hanscom Air Force Base by the vertical gradient freeze VGF method utilizing a submerged heater. Electromagnetic stirring can be induced in the gallium-antimonide melt just above the crystal growth interface by applying a weak radial electric current in the melt together with a weak axial magnetic field. A force convection in the melt can be induced by rotating the heater. This paper uses a Chebyshev spectral collocation method and investigates the effects of heater rotation and electromagnetic stirring on the melt motion during the VGF process using a submerged heater. Clockwise and counterclockwise rotations of the heater augment and opposes the flow induced by the electromagnetic stirring, respectively. The radial velocity along the crystal-melt interface is proportional to both the strength of the electromagnetic stirring and the clockwise rotation of the heater. A relatively low rotation rate in the clockwise direction significantly increases this radial velocity.

Descriptors:

• *SEMICONDUCTORS
• *CRYSTAL GROWTH
• *RADIAL VELOCITY
• MAGNETIC FIELDS
• ELECTROMAGNETIC PROPERTIES
• MELTS
• GALLIUM ANTIMONIDES
• ROTATION
• CONVECTION
• ELECTRIC FIELDS
• CRYSTALS

Subject Categories:

• Electrical and Electronic Equipment
• Crystallography
• Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE