Development and evaluation of die materials for use in the growth of silicon ribbons by the inverted ribbon growth process. Task II. LSSA Project. Quarterly report No. 5, October 1-December 31, 1978
Several ribbon growth experiments were performed in the Mark II ribbon growth facility from V-shaped dies coated with CVD Si/sub 3/N/sub 4/. The most significant result was the ability to perform five consecutive growth runs from the same die without mechanical degradation of the die through temperature cycling. The die was made from vitreous carbon coated with CVD Si/sub 3/N/sub 4/. Silicon oxynitride, Si/sub 2/N/sub 2/O, was examined with respect to thermal stability in contact with molten silicon. The results of x-ray analysis indicate that this material is converted to both ..cap alpha..- and ..beta..-Si/sub 3/N/sub 4/ in the presence of molten silicon. The latter phase is the dominant phase. Experiments on the stability of CVD SiO/sub x/N/sub y/ show that this material can be maintained in contact with molten silicon (sessile drop test) for greater than 30 h at 1450/sup 0/C without total decomposition. These layers are converted mainly to ..beta..-Si/sub 3/N/sub 4/. The fabrication of coated EFG-type dies is proving difficult because of thermal expansion mismatch between layer and substrate and instability of substrate materials at high temperature. Self-supporting CVD dies have been prepared on silicon substrates but the wall thickness is not greater than about 50 ..mu..m. Experiments are continuing.
- Research Organization:
- RCA Labs., Princeton, NJ (USA)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- NAS-7-100-954901
- OSTI ID:
- 5927633
- Report Number(s):
- DOE/JPL/954901-5
- Country of Publication:
- United States
- Language:
- English
Similar Records
Development and evaluation of die materials for use in the growth of silicon ribbons by the inverted ribbon growth process. Task II. LSA Project. Final report, October 1, 1977-March 31, 1979
Development and evaluation of die materials for use in the growth of silicon ribbons by the inverted ribbon growth process: Task II. LSSA Project. Quarterly report No. 1
Related Subjects
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
CRYSTAL GROWTH
DEPOSITION
DIES
DIRECT ENERGY CONVERTERS
ELEMENTS
EXPANSION
FABRICATION
NITRIDES
NITROGEN COMPOUNDS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PNICTIDES
SEMIMETALS
SILICON
SILICON COMPOUNDS
SILICON NITRIDES
SILICON SOLAR CELLS
SOLAR CELLS
STABILITY
SURFACE COATING
THERMAL EXPANSION