Anh K Hoang

US Patent:

6572265, Jun 3, 2003

Filed:

Apr 20, 2001

Appl. No.:

09/839857

Inventors:

John P. Gotthold - Sunnyvale CA
Anh N. Hoang - San Jose CA
Surinder S. Sandhu - Santa Clara CA
John Leonard Shaver - San Francisco CA
Terry M. Stapleton - San Jose CA

Assignee:

Luxtron Corporation - Santa Clara CA

International Classification:

G01J 508

US Classification:

374161, 374131, 374208, 385 12, 385147, 2504581, 2504591, 250234, 2505781

Abstract:

A temperature sensor utilizing optical temperature measuring techniques is constructed to make firm contact with a surface whose temperature is being measured, an example application being the monitoring of semiconductor wafers or flat panel displays while being processed. A cap is mounted near but spaced apart from an end of a lightwave guide, with a resilient element that applies force of the cap against a surface whose temperature is being measured as the cap is urged toward the optical fiber end. An optical temperature sensing element, such as luminescent material or a surface of known emissivity, is carried within the cap. A bellows with a closed end conveniently serves as both the cap and the resilient element. An alternative temperature measuring device installs an optical temperature sensing material within a test substrate behind an optical window, and then views the sensing material through the window.

US Patent:

6654132, Nov 25, 2003

Filed:

May 24, 2000

Appl. No.:

09/577795

Inventors:

Charles W. Schietinger - Portland OR
Anh N. Hoang - San Jose CA
Dmitry V. Bakin - San Jose CA

Assignee:

Luxtron Corporation - Santa Clara CA

International Classification:

G01B 1128

US Classification:

356630, 356625, 356600, 3562372

Abstract:

A characteristic of a surface is measured by illuminating the surface with optical radiation over a wide angle and receiving radiation reflected from the surface over an angle that depends on the extend of the illumination angle. An emissivity measurement is made for the surface, and, alternatively, if a reflectivity measurement is made, it becomes more accurate. One application is to measure the thickness of a layer or layers, either a layer made of transparent material or a metal layer. A one or multiple wavelength technique allow very precise measurements of layer thickness. Noise from ambient radiation is minimized by modulating the radiation source at a frequency where such noise is a minimum or non-existent. The measurements may be made during processing of the surface in order to allow precise control of processing semiconductor wafers, flat panel displays, or other articles. A principal application is in situ monitoring of film thickness reduction by chemical-mechanical-polishing (CMP).

US Patent:

6934040, Aug 23, 2005

Filed:

Sep 26, 2003

Appl. No.:

10/672558

Inventors:

Charles W. Schietinger - Portland OR, US
Anh N. Hoang - San Jose CA, US
Dmitry V. Bakin - San Jose CA, US

Assignee:

Luxtron Corporation - Santa Clara CA

International Classification:

G01B011/28

US Classification:

356630, 356600, 3562372

Abstract:

A characteristic of a surface is measured by illuminating the surface with optical radiation over a wide angle and receiving radiation reflected from the surface over an angle that depends on the extend of the illumination angle. An emissivity measurement is made for the surface, and, alternatively, if a reflectivity measurement is made, it becomes more accurate. One application is to measure the thickness of a layer or layers, either a layer made of transparent material or a metal layer. A one or multiple wavelength technique allow very precise measurements of layer thickness. Noise from ambient radiation is minimized by modulating the radiation source at a frequency where such noise is a minimum or non-existent. The measurements may be made during processing of the surface in order to allow precise control of processing semiconductor wafers, flat panel displays, or other articles. A principal application is in situ monitoring of film thickness reduction by chemical-mechanical-polishing (CMP).

US Patent:

7042581, May 9, 2006

Filed:

Dec 15, 2004

Appl. No.:

11/013070

Inventors:

Charles W. Schietinger - Portland OR, US
Anh N. Hoang - San Jose CA, US
Dmitry V. Bakin - San Jose CA, US

Assignee:

Luxtron Corporation - Santa Clara CA

International Classification:

G01B 11/28
G01B 11/02

US Classification:

356630, 356503, 3562371, 3562372

Abstract:

A characteristic of a surface is measured by illuminating the surface with optical radiation over a wide angle and receiving radiation reflected from the surface over an angle that depends on the extend of the illumination angle. An emissivity measurement is made for the surface, and, alternatively, if a reflectivity measurement is made, it becomes more accurate. One application is to measure the thickness of a layer or layers, either a layer made of transparent material or a metal layer. A one or multiple wavelength technique allow very precise measurements of layer thickness. Noise from ambient radiation is minimized by modulating the radiation source at a frequency where such noise is a minimum or non-existent. The measurements may be made during processing of the surface in order to allow precise control of processing semiconductor wafers, flat panel displays, or other articles. A principal application is in situ monitoring of film thickness reduction by chemical-mechanical-polishing (CMP).

US Patent:

7330333, Feb 12, 2008

Filed:

Jun 16, 2004

Appl. No.:

10/870789

Inventors:

Myeong Eop Kim - San Jose CA, US
Tho Pham - Milpitas CA, US
Anh Hoang - Santa Clara CA, US
Yun Sik Han - Cupertino CA, US

Assignee:

Samsung Electronics Co., Ltd. - Suwon

International Classification:

G11B 5/00

US Classification:

360 9701

Abstract:

A hard disk drive with a post that extends from a base of a base plate. The base has a slot adjacent to the post. The slot attenuates a shock wave that propagates through the base plate of the drive.

US Patent:

8593196, Nov 26, 2013

Filed:

Apr 30, 2012

Appl. No.:

13/459659

Inventors:

Ravi Karapatti Ramaswami - Cupertino CA, US
Vasu P. Ganti - Los Altos CA, US
Anh Hoang - Fremont CA, US

Assignee:

Apple Inc. - Cupertino CA

International Classification:

H03H 11/26

US Classification:

327276, 327279

Abstract:

A system and method for efficiently performing timing characterization of regions of an integrated circuit. An integrated circuit has monitors distributed in different physical regions across its die. Each monitor includes timing characterization and self-test circuitry. This circuitry includes one or more tunable delay lines used during timing measurements. The circuitry verifies the tunable delay lines are defect free prior to the timing measurements. If defects are detected, but tunable delay lines may still be used, a scaling factor may be generated for a failing tunable delay line. The scaling factor may be used during subsequent timing measurements to maintain a high accuracy for the measurements. The timing measurements may determine a particular physical region of the die provides fast or slow timing values. The resulting statistics of the timing measurements may be used to change an operational mode of the IC in at least the particular region.

US Patent:

20030206573, Nov 6, 2003

Filed:

May 30, 2003

Appl. No.:

10/452551

Inventors:

John Gotthold - Sunnyvale CA, US
Anh Hoang - San Jose CA, US
Surinder Sandhu - Santa Clara CA, US
John Shaver - San Francisco CA, US
Terry Stapleton - San Jose CA, US

International Classification:

G01J005/00

US Classification:

374/132000, 374/121000, 374/130000

Abstract:

A temperature sensor utilizing optical temperature measuring techniques is constructed to make firm contact with a surface whose temperature is being measured, an example application being the monitoring of semiconductor wafers or flat panel displays while being processed. A cap is mounted near but spaced apart from an end of a lightwave guide, with a resilient element that applies force of the cap against a surface whose temperature is being measured as the cap is urged toward the optical fiber end. An optical temperature sensing element, such as luminescent material or a surface of known emissivity, is carried within the cap. A bellows with a closed end conveniently serves as both the cap and the resilient element. An alternative temperature measuring device installs an optical temperature sensing material within a test substrate behind an optical window, and then views the sensing material through the window.

US Patent:

20070171958, Jul 26, 2007

Filed:

Jan 23, 2006

Appl. No.:

11/337641

Inventors:

Anh Hoang - San Jose CA, US
Terry Stapleton - San Jose CA, US

International Classification:

G01J 5/00
G01K 11/00

US Classification:

374161000, 374131000

Abstract:

A probe for use within a high voltage and high current electrical device is disclosed. The probe comprises an optical fiber, a substrate having a slot, and a photoluminescent material. The fiber has a first and second end and is configured to convey an activation light from the first to second end. A portion of the fiber is within the slot such that the slot receives the second end of the fiber. Emission of the photoluminescent material, as a function of temperature, is known. The photoluminescent material is disposed within at least a portion of the slot that faces the second end of the fiber so that they are in optical communication with each other. A change in intensity of a luminescent light emitted back into the fiber by the photoluminescent material when the activation light is conveyed by the fiber onto the photoluminescent material provides an indication of the integrity of the electrical device.