Mohammed R Alam

Author:

Mohammed B. Alam

ISBN #:

0792001141

Author:

Mohammed Badrul Alam

ISBN #:

8170990793

Author:

Mohammed Badrul Alam

ISBN #:

8187943947

US Patent:

46422277, Feb 10, 1987

Filed:

Jan 20, 1984

Appl. No.:

6/572604

Inventors:

Richard C. Flagan - Pasadena CA
Mohammed K. Alam - Athens OH

Assignee:

California Institute of Technology - Pasadena CA

International Classification:

C01B 3302

US Classification:

423349

Abstract:

A method and apparatus is disclosed for producing large particles of material from gas, or gases, containing the material (e. g. , silicon from silane) in a free-space reactor comprised of a tube (20) and controlled furnace (25). A hot gas is introduced in the center of the reactant gas through a nozzle (23) to heat a quantity of the reactant gas, or gases, to produce a controlled concentration of seed particles (24) which are entrained in the flow of reactant gas, or gases. The temperature profile (FIG. 4) of the furnace is controlled for such a slow, controlled rate of reaction that virtually all of the material released condenses on seed particles and new particles are not nucleated in the furnace. A separate reactor comprised of a tube (33) and furnace (30) may be used to form a seed aerosol which, after passing through a cooling section (34) is introduced in the main reactor tube (34) which includes a mixer (36) to mix the seed aerosol in a controlled concentration with the reactant gas or gases.