Process and apparatus for obtaining silicon from fluosilicic acid

Patent · Tue Jun 28 00:00:00 EDT 1988

OSTI ID:866634

Sanjurjo, Angel ^[1]

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1. San Jose, CA

Process and apparatus for producing low cost, high purity solar grade silicon ingots in single crystal or quasi single crystal ingot form in a substantially continuous operation in a two stage reactor starting with sodium fluosilicate and a metal more electropositive than silicon (preferably sodium) in separate compartments having easy vapor transport therebetween and thermally decomposing the sodium fluosilicate to cause formation of substantially pure silicon and a metal fluoride which may be continuously separated in the melt and silicon may be directly and continuously cast from the melt.

• DOE Contract Number: 954471-NAS 7-100
• Assignee: SRI International (Menlo Park, CA)
• Patent Number(s): US 4753783
• Application Number: 06/802,633
• OSTI ID: 866634
• Country of Publication: United States
• Language: English

Related Subjects

process
apparatus
obtaining
silicon
fluosilicic
acid
producing
cost
purity
solar
grade
ingots
single
crystal
quasi
ingot
form
substantially
continuous
operation
stage
reactor
starting
sodium
fluosilicate
metal
electropositive
preferably
separate
compartments
easy
vapor
transport
therebetween
thermally
decomposing
formation
pure
fluoride
continuously
separated
melt
directly
cast
fluosilicic acid
sodium fluosilicate
thermally decomposing
continuous operation
substantially pure
single crystal
solar grade
stage reactor
purity solar
obtaining silicon
metal fluoride
substantially continuous
separate compartments
preferably sodium
pure silicon
vapor transport
silicon ingots
quasi single
reactor starting
grade silicon
continuously separated
ingot form
silicic acid
continuously cast
crystal ingot
/423/