Xing S Chen

US Patent:

6388226, May 14, 2002

Filed:

Feb 10, 2000

Appl. No.:

09/502087

Inventors:

Donald K. Smith - Belmont MA
Xing Chen - Lexington MA
William M. Holber - Winchester MA
Eric Georgelis - Canton MA

Assignee:

Applied Science and Technology, Inc. - Wilmington DE

International Classification:

B23K 1000

US Classification:

21912157, 21912154, 21912143, 21912159, 156345, 31511151

Abstract:

An improved toroidal low-field plasma source allows plasma ignition within a wider range of gas conditions than permitted by prior art plasma sources. Power efficiency of the plasma source is improved by automatically adjusting the power delivered to the plasma based on the load to the power supply. The plasma source can be operated over a wider pressure range than allowed by prior art plasma sources. The plasma source can be operated so as to increase the output of atomic species from the source. The plasma source can be operated to increase the etch rate of organic materials. The plasma source can efficiently remove hazardous gas compounds from effluent gas streams by converting them into scrubbable products.

US Patent:

6486431, Nov 26, 2002

Filed:

Sep 12, 2000

Appl. No.:

09/659881

Inventors:

Donald K. Smith - Belmont MA
Xing Chen - Cambridge MA
William M. Holber - Winchester MA
Eric Georgelis - Canton MA

Assignee:

Applied Science Technology, Inc. - Wilmington MA

International Classification:

B23K 1000

US Classification:

21912157, 21912143, 21912144, 21912159, 31511151, 156345

Abstract:

An apparatus for dissociating gases includes a plasma chamber that may be formed from a metallic material and a transformer having a magnetic core surrounding a portion of the plasma chamber and having a primary winding. The apparatus also includes one or more switching semiconductor devices that are directly coupled to a voltage supply and that have an output coupled to the primary winding of the transformer. The one or more switching semiconductor devices drive current in the primary winding that induces a potential inside the chamber that forms a plasma which completes a secondary circuit of the transformer.

US Patent:

6552296, Apr 22, 2003

Filed:

Sep 17, 2001

Appl. No.:

09/953763

Inventors:

Donald K. Smith - Belmont MA
Xing Chen - Cambridge MA
William M. Holber - Winchester MA
Eric Georgelis - Canton MA

Assignee:

Applied Science and Technology, Inc. - Wilmington MA

International Classification:

B23K 1000

US Classification:

21912143, 21912141, 21912142, 21912157, 31511151, 156345

Abstract:

An improved toroidal low-field plasma source allows plasma ignition within a wider range of gas conditions than permitted by prior art plasma sources. Power efficiency of the plasma source is improved by automatically adjusting the power delivered to the plasma based on the load to the power supply. The plasma source can be operated over a wider pressure range than allowed by prior art plasma sources. The plasma source can be operated so as to increase the output of atomic species from the source. The plasma source can be operated to increase the etch rate of organic materials. The plasma source can efficiently remove hazardous gas compounds from effluent gas streams by converting them into scrubbable products.

US Patent:

6559408, May 6, 2003

Filed:

May 10, 2002

Appl. No.:

10/143061

Inventors:

Donald K. Smith - Belmont MA
Xing Chen - Winchester MA
William M. Holber - Winchester MA
Eric Georgelis - Canton MA

Assignee:

Applied Science Technology, Inc. - Wilmington MA

International Classification:

B23K 1000

US Classification:

21912157, 21912154, 21912143, 156345, 31511151

Abstract:

An apparatus for dissociating gases includes a plasma chamber that may be formed from a metallic material and a transformer having a magnetic core surrounding a portion of the plasma chamber and having a primary winding. The apparatus also includes one or more switching semiconductor devices that are directly coupled to a voltage supply and that have an output coupled to the primary winding of the transformer. The one or more switching semiconductor devices drive current in the primary winding that induces a potential inside the chamber that forms a plasma which completes a secondary circuit of the transformer.

US Patent:

6664497, Dec 16, 2003

Filed:

May 10, 2002

Appl. No.:

10/143070

Inventors:

Donald K. Smith - Belmont MA
Xing Chen - Winchester MA
William M. Holber - Winchester MA
Eric Georgelis - Canton MA

Assignee:

Applied Science and Technology, Inc. - Wilmington MA

International Classification:

B23K 1000

US Classification:

21912157, 21912154, 21912143, 21912159, 20429831, 156345

Abstract:

An apparatus for dissociating gases includes a plasma chamber that may be formed from a metallic material and a transformer having a magnetic core surrounding a portion of the plasma chamber and having a primary winding. The apparatus also includes one or more switching semiconductor devices that are directly coupled to a voltage supply and that have an output coupled to the primary winding of the transformer. The one or more switching semiconductor devices drive current in the primary winding that induces a potential inside the chamber that forms a plasma which completes a secondary circuit of the transformer.

US Patent:

6815633, Nov 9, 2004

Filed:

Mar 12, 2001

Appl. No.:

09/804650

Inventors:

Xing Chen - Lexington MA
William M. Holber - Winchester MA
Andrew Barnett Cowe - Andover MA
Eric Georgelis - Canton MA
Andrzej Bortkiewicz - Hamilton MA

Assignee:

Applied Science Technology, Inc. - Wilmington MA

International Classification:

B23K 1000

US Classification:

21912154, 21912157, 21912143, 21912159, 15634538, 15634548, 31511151

Abstract:

Apparatus for dissociating gases includes a plasma chamber comprising a gas. A first transformer having a first magnetic core surrounds a first portion of the plasma chamber and has a first primary winding. A second transformer having a second magnetic core surrounds a second portion of the plasma chamber and has a second primary winding. A first solid state AC switching power supply including one or more switching semiconductor devices is coupled to a first voltage supply and has a first output that is coupled to the first primary winding. A second solid state AC switching power supply including one or more switching semiconductor devices is coupled to a second voltage supply and has a second output that is coupled to the second primary winding. The first solid state AC switching power supply drives a first AC current in the first primary winding. The second solid state AC switching power supply drives a second AC current in the second primary winding.

US Patent:

6872909, Mar 29, 2005

Filed:

Apr 16, 2003

Appl. No.:

10/417408

Inventors:

William M. Holber - Winchester MA, US
Xing Chen - Lexington MA, US
Andrew B. Cowe - Andover MA, US
Matthew M. Besen - Andover MA, US
Susan C. Trulli - Lexington MA, US
Shouqian Shao - Winchester MA, US

Assignee:

Applied Science and Technology, Inc. - Wilmington MA

International Classification:

B23K010/00

US Classification:

21912152, 21912155

Abstract:

Plasma ignition and cooling apparatus and methods for plasma systems are described. An apparatus can include a vessel and at least one ignition electrode adjacent to the vessel. A total length of a dimension of the at least one ignition electrode is greater than 10% of a length of the vessel's channel. The apparatus can include a dielectric toroidal vessel, a heat sink having multiple segments urged toward the vessel by a spring-loaded mechanism, and a thermal interface between the vessel and the heat sink. A method can include providing a gas having a flow rate and a pressure and directing a portion of the flow rate of the gas into a vessel channel. The gas is ignited in the channel while the remaining portion of the flow rate is directed away from the channel.

US Patent:

6924455, Aug 2, 2005

Filed:

Jan 26, 2001

Appl. No.:

09/774165

Inventors:

Xing Chen - Cambridge MA, US
Donald K. Smith - Belmont MA, US
William M. Holber - Winchester MA, US

Assignee:

Applied Science & Technology, Inc. - Wilmington MA

International Classification:

B23K010/00

US Classification:

21912141, 21912152, 21912143, 21912148, 21912154, 31511151, 20429831

Abstract:

A material processing apparatus having an integrated toroidal plasma source is described. The material processing apparatus includes a plasma chamber that comprises a portion of an outer surface of a process chamber. A transformer having a magnetic core surrounds a portion of the plasma chamber. The transformer has a primary winding. A solid state AC switching power supply comprising one or more switching semiconductor devices is coupled to a voltage supply and has an output that is coupled to the primary winding. The solid state AC switching power supply drives an AC current in the primary winding that induces an AC potential inside the chamber that directly forms a toroidal plasma that completes a secondary circuit of the transformer and dissociates the gas.