Heat exchanger-ingot casting/slicing process. Silicon Sheet Growth Development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Eighth quarterly progress report, July 1, 1977--September 30, 1977
Graded crucibles have been developed which are dense enough to avoid penetration of the molten silicon and weak enough to fracture during the cool-down cycle. These crucibles have been used to cast crack-free silicon ingots up to 3.3 kg. Significant progress has been made in the crystallinity of the samples cast. Solar cells made from one of the ingots have yielded over 9% conversion efficiency. The source of silicon carbide in the cast silicon has been identified, both theoretically and experimentally, to be associated with the use of graphite retainers in contact with the crucible. Both 45 ..mu..m and 30 ..mu..m diamonds can be used for efficient slicing of silicon. Wafers sliced with 45 ..mu..m diamond plated wire show a surface roughness of +-0.5 ..mu..m and extent of damage of 3 ..mu..m. In an effort to avoid diamond pullout from impregnated wire it was found that a layer of 0.3 mil thick plating is sufficient to encapsulate the diamonds. A projected cost analysis has shown that the add-on cost of casting and slicing of silicon is $11.57 per square meter.
- Research Organization:
- Crystal Systems, Inc., Salem, Mass. (USA)
- DOE Contract Number:
- NAS-7-100-954373
- OSTI ID:
- 5358606
- Report Number(s):
- ERDA/JPL/954373-77/3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Heat exchanger-ingot casting/slicing process. Silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Final report, Phase I, November 20, 1975--November 20, 1977
Silicon ingot casting: Heat Exchanger Method (HEM)/multi-wire slicing: Fixed Abrasive Slicing Technique (FAST), Phase IV. Quarterly progress report No. 2, April 1, 1980-June 30, 1980
Related Subjects
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
36 MATERIALS SCIENCE
360601 -- Other Materials-- Preparation & Manufacture
CARBIDES
CARBON
CARBON COMPOUNDS
CASTING
CHEMICAL REACTIONS
COST
COVERINGS
CRUCIBLES
CUTTING
DIAMONDS
DIRECT ENERGY CONVERTERS
ELEMENTS
FABRICATION
IMPURITIES
MACHINING
MINERALS
NONMETALS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
RESEARCH PROGRAMS
SEMIMETALS
SILICON
SILICON CARBIDES
SILICON COMPOUNDS
SILICON SOLAR CELLS
SOLAR CELLS
WIRES