The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 27, 2010
Filed:
Jan. 10, 2007
Junhua Ding, Tewksbury, MA (US);
Michael L'bassi, Sterling, MA (US);
Kaveh H. Zarkar, Andover, MA (US);
William R. Clark, Hampstead, NH (US);
Junhua Ding, Tewksbury, MA (US);
Michael L'Bassi, Sterling, MA (US);
Kaveh H. Zarkar, Andover, MA (US);
William R. Clark, Hampstead, NH (US);
MKS Instruments, Inc., Wilmington, MA (US);
Abstract
An integrated pressure and flow ratio control system includes N mass flow controllers MFC(i=1, . . . , N) that each control the flow rate of a fluid F(i=1, . . . , N) flowing into a processing chamber. These N mass flow controllers are linked together by a digital communication network. One of the mass flow controllers is a master MFC, and the remaining N−1 MFCs are slave MFCs. The master MFC receives a pressure set point and a plurality N of flow ratio set points from a host controller, and communicates these set points to all the slave MFCs. In this way, the pressure in the chamber is maintained at the pressure set point and the flow ratios Q/Qare maintained at the flow ratio set points, where Qis flow rate of the i-th fluid F, and Q=Q+Q+ . . . Qis the sum of all N flow rates.