Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Low cost silicon solar array project, silicon materials task. Establishment of the feasibility of a process capable of low-cost, high-volume production of silane (Step I) and the pyrolysis of silane to semiconductor-grade silicon (Step II). Quarterly progress report, October--December 1977. [Silicon tetrachlorides]

Technical Report ·
DOI:https://doi.org/10.2172/6602475· OSTI ID:6602475

Kinetics and equilibria for the hydrogenation of silicon tetrachloride have shown that conversion to trichlorosilane is substantially increased at higher operating pressures; these results greatly improve the practicality of the overall process. An integrated process development unit for converting metallurgical silicon and hydrogen to high-purity silane has been commissioned. A quartz fluid-bed reactor capable of operating at temperatures of up to 1000/sup 0/C was designed, constructed, and successfully operated. A total of 6.7 Kg of silicon powder was produced in two separate experiments in the free-space reactor without opening the reactor between experiments. No measurable impurities were detected in the silicon powder produced by the free-space reactor, using the cathode layer emission spectroscopic technique. A 152 mm-diameter melt consolidation apparatus was attached to the free-space reactor. The first objective for the overall process was the definition of a preliminary set of functional specifications. All process design efforts are based on these specifications. Preliminary block flow diagrams and heat and material balances for every battery-limit stream were completed for the 25 MT/year experimental facility. A brief parametric study was conducted to select an optimum range of operating pressures for the distillation columns. Conceptual designs have been initiated for the hydrogenation reactor, the free-space reactor, and the consolidation system.

Research Organization:
Union Carbide Corp., Tarrytown, NY (USA)
DOE Contract Number:
NAS-7-100-954334
OSTI ID:
6602475
Report Number(s):
DOE/JPL/954334-5
Country of Publication:
United States
Language:
English