Chemistry of inorganic compounds – Silicon or compound thereof – Elemental silicon
Reexamination Certificate
2007-08-17
2010-10-26
Bos, Steven (Department: 1793)
Chemistry of inorganic compounds
Silicon or compound thereof
Elemental silicon
C423S348000, C427S213000, C427S215000
Reexamination Certificate
active
07820126
ABSTRACT:
Methods and apparatus for the commercial-scale production of purified polycrystalline silicon granules with one or more tailored levels of n- and p-type impurities from an impure silicon source such as, for example, metallurgical-grade silicon. Purification systems and methods involve: (1) one or more series of temperature controlled reactors or vessels provided with dual fluidized beds wherein solids and gases are transported so that varying degrees of purification and deposition of solid silicon is accomplished by strict control of temperature and residence time; (2) separation and recovery of the compounds of high-melting-point impurities such as, for example, FeSi and FeI2; (3) purification, separation, and recycling of silicon tetraiodide; (4) separation and recovery of iodide compounds of lower-boiling-point liquid impurities such as for example, AlI3, in a continuous fractional distillation column, facilitated by an iodine reflux; (5) separation and recovery of very fine solid particles including impurity iodides and elemental silicon in a liquid mixture downstream of a fractional distillation column; (6) recovery of input iodine from the oxidation of both solid and liquid iodide impurity waste streams from the process.
REFERENCES:
patent: 3006737 (1961-10-01), Moates et al.
patent: 3020129 (1962-02-01), Herrick
patent: 3442622 (1969-05-01), Monnier et al.
patent: 4092446 (1978-05-01), Padovani et al.
patent: 4117094 (1978-09-01), Blocher et al.
patent: 4138509 (1979-02-01), Ingle et al.
patent: 4213937 (1980-07-01), Padovani et al.
patent: 4304763 (1981-12-01), Dietl et al.
patent: 4388286 (1983-06-01), Kapur et al.
patent: 4910163 (1990-03-01), Jain
patent: 5788945 (1998-08-01), Schei
patent: 5798137 (1998-08-01), Lord et al.
patent: 6281098 (2001-08-01), Wang et al.
patent: 6468886 (2002-10-01), Wang et al.
patent: 6712908 (2004-03-01), Wang et al.
patent: 6780665 (2004-08-01), Billiet et al.
patent: 6929537 (2005-08-01), Kajimoto
patent: WO 02/40407 (2002-05-01), None
patent: WO 2006/137098 (2006-12-01), None
Ciszek et al. “Alternative Solar-Grade Silicon Feedstock Approaches”, National Renewable Energy Laboratory Conference Paper, Oct. 2001.
Wang et al. “Atmospheric Pressure Iodine Vapor Transport for Thin-Silicon Growth”, National Renewable Energy Laboratory Conference Paper, Oct. 2001.
Wang et al. “Growth of Large-Grain Silicon Layers by Atmospheric Iodine Vapor Transport”, Journal of the Electrochemical Society 147 (5) 1945-1949 (2000).
Glang, et al. Impurity Introduction during Epitaxial Growth of Silicon. IBM Journal. 1960; 299-301.
Glang, et al. Silicon. The Art and Science of Growing Crystals. John Whiley and Sons. New York, NY. 1963; 80-87.
Herrick, et al. High-purity Silicon from an Iodide Process Pilot Plant. J. Electrochem. Soc. 1960; 107(2): 111-117.
Hillel, et al. Stabilité Thermique et Propriétés Thermodynamiques de lodures de Phosphore a l'état Condensé et Gaseux. J. Chimie Physique. 1976; 73(9-10): 845-848.
Litton, et al. High Purity Silicon. J. Electrochem. Soc. 1954; 101(6): 287-292.
Szekely, G. Preparation of Pure Silicon by Hydrogen Reduction of SiliconTetraiodide. J. Electrochem. Soc. 1957; 104(11): 663-667.
Bos Steven
Iosil Energy Corporation
Wilson Sonsini Goodrich & Rosati
Zimmer Anthony J
LandOfFree
Method and apparatus for improving the efficiency of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for improving the efficiency of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for improving the efficiency of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4209794