Aerosol reactor production of uniform submicron powders

Patent · Tue Feb 19 04:00:00 EST 1991

OSTI ID:7175089

Flagan, R C; Wu, J J

A method of producing submicron non agglomerated particles in a single stage reactor includes introducing a reactant or mixture of reactants at one end while varying the temperature along the reactor to initiate reactions at a low rate. As homogeneously small numbers of seed particles generated in the initial section of the reactor progress through the reactor, the reaction is gradually accelerated through programmed increases in temperature along the length of the reactor to promote particle growth by chemical vapor deposition while minimizing agglomerate formation by maintaining a sufficiently low number concentration of particles in the reactor such that coagulation is inhibited within the residence time of particles in the reactor. The maximum temperature and minimum residence time is defined by a combination of temperature and residence time that is necessary to bring the reaction to completion. In one embodiment, electronic grade silane and high purity nitrogen are introduced into the reactor and temperatures of approximately 770 K to 1550 K are employed. In another embodiment silane and ammonia are employed at temperatures from 750 K to 1800 K. 7 figures.

• Assignee: California Institute of Technology, Los Angeles, CA (United States)
• Patent Number(s): A; US 4994107
• Application Number: PPN: US 7-248486
• OSTI ID: 7175089
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000 -- Solar Collectors & Concentrators
36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
AGGLOMERATION
CHEMICAL COATING
CHEMICAL REACTORS
CHEMICAL VAPOR DEPOSITION
CONTROL
DEPOSITION
EQUIPMENT
FLAT PLATE COLLECTORS
HYDRIDES
HYDROGEN COMPOUNDS
MATERIALS
MITIGATION
NITRIDES
NITROGEN COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC SILICON COMPOUNDS
PNICTIDES
SILANES
SILICON COMPOUNDS
SILICON NITRIDES
SOLAR COLLECTORS
SOLAR EQUIPMENT
SURFACE COATING
TEMPERATURE CONTROL