Method of high purity silane preparation

Patent · Sat Jan 01 00:00:00 EST 2000

OSTI ID:873162

Tsuo, Y Simon ^[1]; Belov, Eugene P ^[2]; Gerlivanov, Vadim G ^[2]; Zadde, Vitali V ^[2]; Kleschevnikova, Solomonida I ^[2]; Korneev, Nikolai N ^[2]; Lebedev, Eugene N ^[2]; Pinov, Akhsarbek B ^[2]; Ryabenko, Eugene A ^[2]; Strebkov, Dmitry S ^[2]; Chernyshev, Eugene A ^[2]

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1. Golden, CO
2. Moscow, RU

A process for the preparation of high purity silane, suitable for forming thin layer silicon structures in various semiconductor devices and high purity poly- and single crystal silicon for a variety of applications, is provided. Synthesis of high-purity silane starts with a temperature assisted reaction of metallurgical silicon with alcohol in the presence of a catalyst. Alcoxysilanes formed in the silicon-alcohol reaction are separated from other products and purified. Simultaneous reduction and oxidation of alcoxysilanes produces gaseous silane and liquid secondary products, including, active part of a catalyst, tetra-alcoxysilanes, and impurity compounds having silicon-hydrogen bonds. Silane is purified by an impurity adsorption technique. Unreacted alcohol is extracted and returned to the reaction with silicon. Concentrated mixture of alcoxysilanes undergoes simultaneous oxidation and reduction in the presence of a catalyst at the temperature -20.degree. C. to +40.degree. C. during 1 to 50 hours. Tetra-alcoxysilane extracted from liquid products of simultaneous oxidation and reduction reaction is directed to a complete hydrolysis. Complete hydrolysis of tetra-alcoxysilane results in formation of industrial silica sol and alcohol. Alcohol is dehydrated by tetra-alcoxysilane and returned to the reaction with silicon.

• Research Organization: Midwest Research Institute, Kansas City, MO (United States)
• DOE Contract Number: AC36-98GO10337
• Assignee: Midwest Research Institute (Kansas City, MO)
• Patent Number(s): US 6103942
• OSTI ID: 873162
• Country of Publication: United States
• Language: English

Related Subjects

method
purity
silane
preparation
process
suitable
forming
layer
silicon
structures
various
semiconductor
devices
poly-
single
crystal
variety
applications
provided
synthesis
high-purity
starts
temperature
assisted
reaction
metallurgical
alcohol
presence
catalyst
alcoxysilanes
formed
silicon-alcohol
separated
products
purified
simultaneous
reduction
oxidation
produces
gaseous
liquid
secondary
including
active
tetra-alcoxysilanes
impurity
compounds
silicon-hydrogen
bonds
adsorption
technique
unreacted
extracted
returned
concentrated
mixture
undergoes
-20
degree
40
50
hours
tetra-alcoxysilane
directed
complete
hydrolysis
results
formation
industrial
silica
sol
dehydrated
silicon structures
silica sol
single crystal
semiconductor device
liquid products
semiconductor devices
liquid product
reduction reaction
crystal silicon
silicon structure
purity silane
metallurgical silicon
hydrogen bonds
layer silicon
/999/423/