Silicon ingot casting: heat exchanger method. Multi-wire slicing: fixed abrasive slicing technique. Phase III. Quarterly progress report No. 4, July 1-September 30, 1979
This contract is for casting silicon ingots by the Heat Exchanger Method (HEM) and slicing by multi-wire Fixed Abrasive Slicing Technique (FAST). Significant advancements have been made in the area of crystal casting. It has been demonstrated that nearly single crystal ingots can be cast with a single HEM solidification of upgraded metallurgical grade silicon. The impurities were rejected to the last material to freeze-near the wall of the crucible. The resistivity of the silicon after directional solidification by HEM was 0.1 to 0.2 ..cap omega..-cm. Macroscopic impurities, presumably SiC, did not break down the solid-liquid interface and, in some cases, caused only localised twin formation. This material may be used for making solar cells directly. The HEM process has been scaled up to solidify 22 cm x 22 cm square cross-section ingots weighing up to 10.5 kg. The 22 cm square cross-section ingot is nearly all single crystal material. For silicon slicing using FAST significant progress has been made in demonstrating high throughput of the slicer and extended life of the wires. Cutting rates exceeded 1986 goals by more than 40%. This has been achieved with the combination of high speeds of the slicer and improvement in the blade. Emphasis in the area of blade development has been with impregnation using CSI technology of impregnating diamonds only in the cutting edge.
- Research Organization:
- Crystal Systems, Inc., Salem, MA (USA)
- DOE Contract Number:
- NAS-7-100-954373
- OSTI ID:
- 5718907
- Report Number(s):
- DOE/JPL/954373-12
- Country of Publication:
- United States
- Language:
- English
Similar Records
Heat-exchanger method, ingot casting. Fixed-abrasive method, multi-wire slicing. Phase II. Silicon-sheet-growth development for the Large-Area Sheet Task of the Low-Cost Solar-Array Project. Final report, November 21, 1977 to November 20, 1978
Heat exchanger method, ingot casting; fixed abrasive method, multi-wire slicing: Phase II. Silicon sheet growth development for the Large-Area Silicon Sheet Task of the Low-Cost Silicon Solar Array Project. Quarterly progress report No. 2, January 1, 1978--March 31, 1978
Related Subjects
36 MATERIALS SCIENCE
HEAT EXCHANGER METHOD
RESEARCH PROGRAMS
SILICON
CRYSTAL GROWTH
CUTTING
ABRASIVES
CRUCIBLES
ELECTRIC CONDUCTIVITY
IMPURITIES
MONOCRYSTALS
SILICON SOLAR CELLS
CRYSTAL GROWTH METHODS
CRYSTALS
DIRECT ENERGY CONVERTERS
ELECTRICAL PROPERTIES
ELEMENTS
EQUIPMENT
MACHINING
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
SEMIMETALS
SOLAR CELLS
SOLAR EQUIPMENT
140501* - Solar Energy Conversion- Photovoltaic Conversion
360601 - Other Materials- Preparation & Manufacture