Thomas G Pratt

US Patent:

6712907, Mar 30, 2004

Filed:

Jun 21, 2001

Appl. No.:

09/887202

Inventors:

Thomas M. Pratt - San Jose CA
Scott Douglas McClelland - San Jose CA
Craig L. Stevens - Ben Lomond CA
Kerry Hopkins - Gilroy CA

Assignee:

Novellus Systems, Inc. - San Jose CA

International Classification:

C23C 1600

US Classification:

118719, 414939

Abstract:

The mechanism comprises a magnetically coupled drive mechanism for transporting semiconductor wafers in a semiconductor wafer processing system. The mechanism includes an actuator within a cylinder that contains a set of magnets that drive a complementary set of magnets inside a carriage along a linear path. The carriage is limited to linear motion via a linear ball slide. The magnets in the actuator and carriage are magnetically coupled in such a way as to prevent angular rotation of the magnets within the actuator. Accordingly, driving elements in the actuator can be moved via rotation of a ball screw shaft coupled to a ball nut affixed to the actuator magnets.

US Patent:

7737035, Jun 15, 2010

Filed:

Oct 3, 2006

Appl. No.:

11/542723

Inventors:

Gary Lind - Paso Robles CA, US
Colin F. Smith - Half Moon Bay CA, US
William Johanson - Gilroy CA, US
Thomas M. Pratt - San Jose CA, US
John Mazzocco - San Jose CA, US

Assignee:

Novellus Systems, Inc. - San Jose CA

International Classification:

H01L 21/44
C23C 16/00

US Classification:

438680, 29 2501, 118715, 118723 VE

Abstract:

An apparatus and method for sealing and unsealing a chemical deposition apparatus in a chemical deposition process chamber includes a microvolume that has dual sealing elements at its periphery. One seal, the outer seal, is used to seal the inside of the microvolume from the main process chamber. The second (inner) seal is used to seal the inside of the microvolume from a vacuum source. The apparatus and process of the present invention has several advantages for enhanced chamber performance.

US Patent:

20080081114, Apr 3, 2008

Filed:

Oct 3, 2006

Appl. No.:

11/542959

Inventors:

William Johanson - Gilroy CA, US
John Mazzocco - San Jose CA, US
David Cohen - San Jose CA, US
Thomas M. Pratt - San Jose CA, US
Gary Lind - Paso Robles CA, US
Peter Krotov - San Jose CA, US

International Classification:

B05D 3/00
B05D 3/04

US Classification:

427273, 427348

Abstract:

Uniform fluid delivery to a substrate is provider using a diffuser. The diffuser is designed with a series of fluid (gas and/or liquid) passages of equal effective length/flow resistance, such that as the fluid passes through the diffuser, the gas exits all areas at the same time and with the same mass flux. These passages may not be physically the same, however they have the same effective length and flow resistance. The diffuser can be implemented using single or multiple stacked layers, and from several to many passages. The net effect is a uniform gas curtain to the wafer. Since the passages through the diffuser are effectively the same, the uniform gas curtain to the wafer is not sensitive to the quantity of gas, the gas flow rate or the gas pressure. Additionally, a faceplate can optionally be used to smooth out any jet effects of the diffuser exit holes.

US Patent:

20080264443, Oct 30, 2008

Filed:

Jan 5, 2004

Appl. No.:

10/752168

Inventors:

Krishnan Shrinivasan - San Jose CA, US
Wilbert G.M. van den Hoek - Saratoga CA, US
Patrick Joyce - Fremont CA, US
Thomas Pratt - San Jose CA, US
Tim Thomas - San Jose CA, US

International Classification:

C23G 1/00
B08B 3/00

US Classification:

134 2, 134111

Abstract:

The present invention pertains to a system for processing semiconductor wafers. The processing may involve the removal of material from the wafers or deposition of material on the wafers. Various aspects of the invention include specialized pressurization, process vessel, recirculation, chemical addition, depressurization, and recapture-recycle subsystems. A solvent delivery mechanism can convert a liquid-state sub-critical solution to a supercritical processing solution and introduce it into a process vessel that contains a batch of wafers. The wafers may be rotated within the supercritical processing solution. The supercritical processing solution is preferably recirculated through the process vessel by a recirculation system. When chemical additives are added to a supercritical solvent, the momentum of the chemical additives are preferably matched to the momentum of the supercritical solvent. Additives may be added at a higher initial flow rate, then ramped down a lower flow rate, e.g., a steady-state flow rate.

US Patent:

D2816334, Dec 3, 1985

Filed:

May 23, 1983

Appl. No.:

6/497398

Inventors:

Thomas A. Pratt - Los Gatos CA

Assignee:

FMC Corporation - Chicago IL

US Classification:

D32 16

US Patent:

D2816342, Dec 3, 1985

Filed:

May 23, 1983

Appl. No.:

6/497399

Inventors:

Thomas A. Pratt - Los Gatos CA

Assignee:

FMC Corporation - Chicago IL

US Classification:

D32 16

US Patent:

63195534, Nov 20, 2001

Filed:

Feb 28, 2000

Appl. No.:

9/514469

Inventors:

Edward J. McInerney - San Jose CA
Thomas M. Pratt - San Jose CA
Shawn D. Hancock - Alviso CA

Assignee:

Novellus Systems, Inc. - San Jose CA

International Classification:

C23C 1600

US Classification:

427250

Abstract:

A multi-station processing chamber in which incompatible processes are performed includes multiple pedestals positioned in wells with annular gaps around the pedestals. Showerheads located above the pedestals flow reactive gases over substrates located on the pedestals. The reactive gases are drawn through the annular gaps by a pressure gradient. The reactive gases are then pumped out of the wells through an exhaust port. The narrow annular gap permits little recirculation of the reactive gases one they are drawn into the wells. Moreover, the showerheads are flush with ceiling of the chamber and the wells contain smooth contours to minimize dead space in the chamber thereby reducing residence time of the reactive gases. An indexing plate is used to lift the substrates off the pedestals and to accurately position the substrates at the next processing station. In one embodiment a purge plate located on the ceiling of the chamber between the showerheads flows an inert gas, such as argon, to further assist in maintaining a separation between the reactive gases.

US Patent:

6143082, Nov 7, 2000

Filed:

Oct 8, 1998

Appl. No.:

9/169624

Inventors:

Edward J. McInerney - San Jose CA
Thomas M. Pratt - San Jose CA
Shawn D. Hancock - Alviso CA

Assignee:

Novellus Systems, Inc. - San Jose CA

International Classification:

C23C 1600

US Classification:

118719

Abstract:

A multi-station processing chamber in which incompatible processes are performed includes multiple pedestals positioned in wells with annular gaps around the pedestals. Showerheads located above the pedestals flow reactive gases over substrates located on the pedestals. The reactive gases are drawn through the annular gaps by a pressure gradient. The reactive gases are then pumped out of the wells through an exhaust port. The narrow annular gap permits little recirculation of the reactive gases once they are drawn into the wells. Moreover, the showerheads are flush with ceiling of the chamber and the wells contain smooth contours to minimize dead space in the chamber thereby reducing residence time of the reactive gases. An indexing plate is used to lift the substrates off the pedestals and to accurately position the substrates at the next processing station. In one embodiment a purge plate located on the ceiling of the chamber between the showerheads flows an inert gas, such as argon, to further assist in maintaining a separation between the reactive gases.