David S Schaefer

US Patent:

7479457, Jan 20, 2009

Filed:

Sep 8, 2005

Appl. No.:

11/220710

Inventors:

Cristian Paduraru - Fremont CA, US
Alan Jensen - White Salmon WA, US
David Schaefer - Vancouver WA, US
Robert Charatan - Portland OR, US
Tom Choi - San Jose CA, US

Assignee:

Lam Research Corporation - Fremont CA

International Classification:

H01L 21/461

US Classification:

438708, 438709, 438727, 438729, 438731

Abstract:

Atomic oxygen generated in oxygen stripping plasmas reacts with and damages low-k dielectric materials during stripping of dielectric post etch residues. While damage of low-k dielectric materials during stripping of dielectric post etch residues is lower with hydrogen stripping plasmas, hydrogen stripping plasmas exhibit lower strip rates. Inclusion of oxygen in a hydrogen stripping plasma improves both photoresist strip rate and uniformity, while maintaining a hydrogen to oxygen ratio avoids low-k dielectric material damage.

US Patent:

7622051, Nov 24, 2009

Filed:

Mar 27, 2003

Appl. No.:

10/401100

Inventors:

David M. Schaefer - Sunnyvale CA, US
Gowri P. Kota - Fremont CA, US

Assignee:

Lam Research Corporation - Fremont CA

International Classification:

B44C 1/22
H01L 21/302

US Classification:

216 67, 216 74, 216 79, 438706, 438710

Abstract:

A method of etching a substrate in a plasma processing chamber is disclosed. The method includes introducing the substrate having thereon an underlying layer, an anti-reflective layer above the underlying layer, and a photo-resist layer above the anti-reflective layer into the chamber. The method also includes flowing a gas mixture into the chamber, the gas mixture includes a flow of a hydrofluorocarbon gas, a flow of fluorocarbon gas, a flow of a halogen-containing gas other than the hydrofluorocarbon gas, and a flow of oxygen gas. The method further includes striking a plasma from the gas mixture. The method additionally includes etching at least through the anti-reflective layer with the plasma.

US Patent:

20130097840, Apr 25, 2013

Filed:

Oct 20, 2011

Appl. No.:

13/277873

Inventors:

David Schaefer - Fremont CA, US
Ambarish Chhatre - San Jose CA, US
Keith William Gaff - Fremont CA, US
Sung Lee - Pleasanton CA, US

Assignee:

Lam Research Corporation - Fremont CA

International Classification:

B23P 11/00
H01L 21/3065

US Classification:

29428, 15634552

Abstract:

A lower electrode assembly useful for supporting a semiconductor substrate in a plasma processing chamber includes a temperature controlled lower base plate, an upper plate, a mounting groove surrounding a bond layer and an edge seal comprising an elastomeric band having an outer concave surface in an uncompressed state, the band mounted in the groove such that upper and lower ends of the band are axially compressed and a maximum outward bulging of the band is no greater than a predetermined distance.

US Patent:

20130340942, Dec 26, 2013

Filed:

Jun 20, 2012

Appl. No.:

13/528194

Inventors:

David Schaefer - Fremont CA, US
Ambarish Chhatre - San Jose CA, US
Keith William Gaff - Fremont CA, US
Brooke Mesler Lai - Fremont CA, US

Assignee:

Lam Research Corporation - Fremont CA

International Classification:

F16J 15/02
H02N 13/00

US Classification:

15634551, 29505, 277628

Abstract:

A lower electrode assembly useful for supporting a semiconductor substrate in a plasma processing chamber includes a temperature controlled lower base plate, an upper plate, a mounting groove surrounding a bond layer and an edge seal comprising an elastomeric band having an outer concave surface in an uncompressed state, the band mounted in the groove such that upper and lower ends of the band are axially compressed and a maximum outward bulging of the band is no greater than a predetermined distance.

US Patent:

20180151331, May 31, 2018

Filed:

Nov 30, 2016

Appl. No.:

15/365864

Inventors:

- Fremont CA, US
David Schaefer - Fremont CA, US
Dan Marohl - San Jose CA, US

International Classification:

H01J 37/32

Abstract:

A system is disclosed for measuring an impedance of a plasma processing chamber. The system includes a radiofrequency signal generator configured to output a radiofrequency signal based on a frequency setpoint and provide an indication of an actual frequency of the radiofrequency signal, where the actual frequency can be different than the frequency setpoint. The system includes an impedance control module including at least one variable impedance control device. A difference between the actual frequency of the radiofrequency signal as output by the radiofrequency signal generator and the frequency setpoint is partially dependent upon a setting of the at least one variable impedance control device and is partially dependent upon the impedance of the plasma processing chamber. The system includes a connector configured to connect with a radiofrequency signal supply line of the plasma processing chamber. The impedance control module is connected between the radiofrequency signal generator and the connector.

US Patent:

20150179412, Jun 25, 2015

Filed:

Dec 20, 2013

Appl. No.:

14/136953

Inventors:

- Fremont CA, US
David Schaefer - Fremont CA, US
Keith Gaff - Fremont CA, US

Assignee:

Lam Research Corporation - Fremont CA

International Classification:

H01J 37/32
H01L 21/3065

Abstract:

An edge ring configured to surround an outer periphery of a substrate support in a plasma processing chamber wherein plasma is generated and used to process a substrate is disclosed, the substrate support comprising a base plate, a top plate, an elastomer seal assembly between the base plate and the top plate, and an elastomer seal configured to surround the elastomer seal assembly. The edge ring includes an upper inner surface having an edge step directed towards an interior portion of the edge ring and arranged to extend from an outer periphery of a top surface of the top plate to an outer periphery of an upper surface of the base plate, a lower inner surface, an outer surface, a lower surface extending from the lower inner surface to the outer surface, and a top surface extending from the outer surface to the upper inner surface.

US Patent:

20150170942, Jun 18, 2015

Filed:

Dec 17, 2013

Appl. No.:

14/109400

Inventors:

- Fremont CA, US
David Schaefer - Fremont CA, US

Assignee:

Lam Research Corporation - Fremont CA

International Classification:

H01L 21/67
H01L 21/70

Abstract:

An installation fixture adapted to mount an elastomer band in a mounting groove around a semiconductor substrate support used for supporting a semiconductor substrate in a plasma processing chamber is disclosed, which includes an annular ring having a vertically extending portion on an outer edge of the ring and adapted to receive the elastomer band, and a base plate configured to be attached to the annular ring, the base plate having a plurality of radially extending portions adapted to receive a plurality of mechanical fasteners at locations corresponding to mounting holes in the semiconductor substrate support.

US Patent:

20140366360, Dec 18, 2014

Filed:

Aug 27, 2014

Appl. No.:

14/470477

Inventors:

- Fremont CA, US
David Schaefer - Fremont CA, US
Sung Lee - Pleasanton CA, US
Dan Haber - Campbell CA, US

International Classification:

H01L 21/687
H01L 21/67

US Classification:

29446

Abstract:

A kit comprising an installation fixture, a plurality of mechanical fasteners and an embedding tool is provided which allows for an elastomer band to be disposed in a mounting groove around a semiconductor substrate support in a manner that relieves the internal stresses of the elastomer band, leading to an elastomer band with a longer operational lifetime. The installation fixture is secured to a substrate support with mechanical fasteners. An elastomer band is placed around an outer circumference of the installation fixture and rotated back and forth to relieve internal stresses of the elastomer band. The fixture is inverted and the elastomer band is slid vertically off the fixture and into the mounting groove. An embedding tool can be used to completely insert the elastomer band into the mounting groove.