Gas control system for chemical vapor deposition system

Patent 4369031 Issued on January 18, 1983. Estimated Expiration Date:

September 15, 2001. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3396955

3917238

Pyrolytic deposition of silicon dioxide on semiconductors using a shrouded boat
Patent #: 4098923
Issued on: 07/04/1978
Inventor: Alberti , et al.

Method of doping inpurities
Patent #: 4100310
Issued on: 07/11/1978
Inventor: Ura , et al.

Apparatus for the treatment of semiconductors
Patent #: 4138306
Issued on: 02/06/1979
Inventor: Niwa

Deposition of doped silicon oxide films Patent #: 4217375
Issued on: 08/12/1980
Inventor: Adams

Inventors

Assignee

Thermco Products Corporation

Application

No. 06/302003 filed on 09/15/1981

US Classes:

432/198, Means supplying a protective or treating agent other than or additional to air118/710, Valve actuator118/715, GAS OR VAPOR DEPOSITION118/724, By means to heat or cool432/55, WITH CONCURRENT CONTROL OR INTER-CONTROL OF DIVERSE OPERABLE ELEMENTS438/935GAS FLOW CONTROL

Examiners

Primary: Camby, John J.

Attorney, Agent or Firm

International Classes

F27D 7/02 (20060101)
F27D 7/00 (20060101)
B01J 4/00 (20060101)
B01J 3/04 (20060101)
C23C 16/52 (20060101)
F27D 19/00 (20060101)

Abstract

A gas flow control system in which several constituent gases are mixed and the mixture delivered through controlled injectors to a processing zone. Mass flow controllers control the injector flows with one of the controllers being a master and the other being slaved to provide a selected percentage of the flow through the master controller. The gas mix is regulated by a mass flow controller on one of the constituents and a flow meter on the other, the flow meter producing an error signal which is used to readjust the total flow through the injectors by control of the master injector flow controller.