Mark A Mccord

US Patent:

6586736, Jul 1, 2003

Filed:

Sep 10, 1999

Appl. No.:

09/394133

Inventors:

Mark A. McCord - Mountain View CA

Assignee:

KLA-Tencor, Corporation - San Jose CA

International Classification:

H01J 37147

US Classification:

250310, 250396 R, 250397

Abstract:

A method and apparatus for generating an image of a sample with a electron beam apparatus is disclosed. The image is generated from a portion of the sample with a measurement device having a source unit for directing an electron beam substantially towards the sample. The measurement device also has a detector for detecting particles that are emitted from the sample, an electrode proximal to the sample having a hole through which the electron beam and a portion of the emitted particles may pass, and an image generator for generating the image of the sample from the detected particles. A first voltage is applied to the electrode when the electron beam is substantially in a center of the hole. The first voltage is selected to control positive charge build up on the sample. A second voltage is applied to the electrode when the electron beam is deflected a predetermined distance from the center of the hole.

US Patent:

6597006, Jul 22, 2003

Filed:

Oct 9, 2001

Appl. No.:

09/974560

Inventors:

Mark McCord - Mountain View CA
Jun Pei - Campbell CA

Assignee:

KLA-Tencor Technologies Corp. - Milpitas CA

International Classification:

G01N 2186

US Classification:

25055919, 25055929, 3562372

Abstract:

Systems and methods for determining the height of a surface of a specimen, such as a surface of a semiconductor device wafer are provided. A system may be configured to generate a comparison signal that may used to alter a Z-axis fine height adjustment of the system. The system may include for example, a processing tool, a metrology tool, or an inspection tool that may be used in semiconductor device fabrication. In this manner, the system may be configured to maintain a constant working distance between the wafer surface and an optical column of the system. A system may include an off-axis dual beam symmetric height sensor due to mechanical constraints of the system. The dual beam symmetric height sensor may provide automatic focusing of the wafer with high precision by substantially eliminating wafer pattern-induced error in comparison signals generated by the system.

US Patent:

6627884, Sep 30, 2003

Filed:

Jul 23, 2001

Appl. No.:

09/912732

Inventors:

Mark A. McCord - Mountain View CA
David Walker - Sunol CA
Jun Pei - Campbell CA
Neil Richardson - Palo Alto CA

Assignee:

KLA-Tencor Technologies Corporation - Milpitas CA

International Classification:

G21K 700

US Classification:

250306, 250305, 250302, 250310, 250251, 378 84, 378 85

Abstract:

Disclosed are methods and apparatus for simultaneously flooding a sample (e. g. , a semiconductor wafer) to control charge and inspecting the sample. The apparatus includes a charged particle beam generator arranged to generate a charged particle beam substantially towards a first portion of the sample and a flood gun for generating a second beam towards a second portion of the sample. The second beam is generated substantially simultaneously with the inspection beam. The apparatus further includes a detector arranged to detect charged particles originating from the sample portion. In a further implementation, the apparatus further includes an image generator for generating an image of the first portion of the sample from the detected particles. In one embodiment, the sample is a semiconductor wafer. In a method aspect, a first area of a sample is flooded with a flood beam to control charge on a surface of the sample.

US Patent:

6664546, Dec 16, 2003

Filed:

Feb 10, 2000

Appl. No.:

09/502554

Inventors:

Mark A. McCord - Mountain View CA
Jan Lauber - Menlo Park CA
Jun Pei - Campbell CA
Jorge P. Fernandez - San Mateo CA

Assignee:

KLA-Tencor - San Jose CA

International Classification:

H01J 3721

US Classification:

250397, 250306, 250310

Abstract:

Disclosed is a method and apparatus for generating an image from a sample. The apparatus includes a charged particle beam generator arranged to generate and control a charged particle beam substantially towards a portion of the sample and a detector arranged to detect charged particles originating from the sample portion to allow generation of an image from the detected charged particles. The apparatus further includes a measurement device arranged to measure a characteristic of the sample portion to obtain a surface voltage value of the sample portion that is exposed to the charged particle beam. For example, the measurement device is an electrostatic voltmeter positioned to obtain a surface voltage value of the exposed sample portion. A charged particle beam is directed substantially towards a portion of the sample under a first set of operating conditions. A surface charge value of the sample portion is obtained under the first set of operating conditions.

US Patent:

6774646, Aug 10, 2004

Filed:

Jan 28, 2002

Appl. No.:

10/058614

Inventors:

Liqun Han - Santa Clara CA
Mark A. McCord - Mountain View CA

Assignee:

KLA-Tencor Corporation - San Jose CA

International Classification:

G01R 3100

US Classification:

324751, 324750

Abstract:

A method for inspecting samples uses a multiple beam electron system having a uniform magnetic focusing field. Deflection of the incident electron beams is produced by deflector plates generating an electrostatic deflection force which produces a uniform force on the electron beams. Thermal field emission sources generate incident electron beams towards at least two portions of the sample. A detector array collects multiple detection electrons.

US Patent:

6828571, Dec 7, 2004

Filed:

Nov 3, 2003

Appl. No.:

10/699708

Inventors:

Mark A. McCord - Los Gatos CA
Jan A. Lauber - San Jose CA
Paul Petric - Pleasanton CA
Ross W. Thompson - Santa Clara CA
Jason Lim - San Jose CA
Frank Y. H. Fan - Pleasanton CA
Gabor D. Toth - San Jose CA

Assignee:

KLA-Tencor Technologies Corporation - Milpitas CA

International Classification:

H01L 2100

US Classification:

2504922, 2504923, 250310, 250306, 250307, 250397, 250396 R, 324750, 324751

Abstract:

One embodiment disclosed relates to a method of setting a surface charge of an area on a substrate to a desired level. The substrate is held on a stage, and a stage bias voltage applied to the stage is controlled. A flood of electrons is directed to the area. The stage bias voltage is controlled such that the surface charge of the area reaches an equilibrium at the desired level. Another embodiment disclosed relates to a method of auto-focusing a main electron beam incident upon an imaging area of a substrate. A monitor electron beam is generated and directed towards a monitoring area of the substrate at a non-perpendicular incidence angle. An in-focus band in data collected from the monitor beam is detected. The focal length of an objective lens focusing the main beam is adjusted based upon a position of the in-focus band.

US Patent:

7091486, Aug 15, 2006

Filed:

Sep 9, 2004

Appl. No.:

10/938841

Inventors:

Mark A. McCord - Los Gatos CA, US
Alan D. Brodie - Palo Alto CA, US

Assignee:

KLA-Tencor Technologies Corporation - Milpitas CA

International Classification:

G01N 23/00
G21K 7/00

US Classification:

250311, 250306, 250307

Abstract:

One embodiment disclosed relates to an electron beam imaging apparatus. An electron source is configured to generate an electron beam, and a beam-limiting aperture is configured to block a portion of the electron beam and to allow transmission of another portion of the electron beam through the aperture. A first detector is configured to detect scattered electrons emitted by the aperture due to the blocked portion of the electron beam. The imaging apparatus may also include a second detector configured to detect scattered electrons emitted by the sample due to impingement of the transmitted portion of the electron beam. A gain control device may also be included to adjust a gain of a detected signal derived from the second detector using a control signal derived from the first detector. Another embodiment disclosed relates to an electron beam lithography apparatus. The lithography apparatus may adjust a pixel dwell time based on a control signal derived from the scattered electrons emitted by the aperture.

US Patent:

7171038, Jan 30, 2007

Filed:

Dec 14, 2001

Appl. No.:

10/017860

Inventors:

David Adler - San Jose CA, US
Kirk Bertsche - San Jose CA, US
Mark McCord - Mountain View CA, US
Stuart Friedman - Palo Alto CA, US

Assignee:

KLA-Tencor Technologies Corporation - Milpitas CA

International Classification:

G06K 9/00

US Classification:

382149, 250307

Abstract:

A method and apparatus for inspection and review of defects is disclosed wherein data gathering is improved. In one embodiment, multiple or segmented detectors are used in a particle beam system.