Cuong Manh Le

US Patent:

6407546, Jun 18, 2002

Filed:

Apr 7, 2000

Appl. No.:

09/545119

Inventors:

Cuong Duy Le - Gilroy CA 95020
Anh The Ngo - San Jose CA 95132

International Classification:

G01B 706

US Classification:

324230, 324202, 324226, 324716, 324 711

Abstract:

A method and system for identifying thicknesses of inspection samples, such as semiconductor wafers is presented. The method and system includes a probe housing, comprising an eddy current sense coil and a linear motion controller, and a computer that controls the linear motion controller and the eddy current sense coil. The computer may be configured to identify a thickness of the inspection sample by a method comprising the generation of a natural intercepting curve based on resistance and reactance measurements of at least two data points. Then, a plurality of corresponding resistance and reactance measurements of a location on the inspection sample is obtained with the eddy current sensor, where the eddy current sensor makes a first measurement at a first distance from the inspection sample, and makes each of the remaining plurality of measurements at a distance that is incrementally further away from the inspection surface. Next, an inspection sample curve is generated based on the plurality of corresponding resistance and reactance measurements obtained from the inspection sample. An intersection point between the natural intercepting curve and the inspection sample curve is also generated.

US Patent:

6549006, Apr 15, 2003

Filed:

Apr 17, 2001

Appl. No.:

09/835975

Inventors:

Cuong Duy Le - Gilroy CA 95020

International Classification:

G01B 706

US Classification:

324230, 324229, 324225, 702104

Abstract:

A method for identifying metal layer thickness of an inspection sample according to one embodiment utilizes an eddy current probe to obtain initial resistance and reactance measurements from the inspection sample. Once these measurements have been obtained, the relative distance between the eddy current probe and inspection sample is increased and terminating resistance and reactance measurements are obtained. An inspection sample intersecting line may then be calculated using the initial and terminating resistance and reactance measurements. An intersecting point between a natural intercepting curve and the inspection sample intersecting line may also be determined. A reactance voltage of the intersecting point along a digital calibration curve is calculated to identify a closest two of a plurality of calibration samples. The metal layer thickness of the inspection sample may then be calculated by performing an interpolation between the identified closest two calibration samples.

US Patent:

6741076, May 25, 2004

Filed:

Apr 14, 2003

Appl. No.:

10/417042

Inventors:

Cuong Duy Le - Morgan Hill CA 95037

International Classification:

G01B 706

US Classification:

324230, 451 8, 702104, 702170

Abstract:

A method for estimating a thickness profile of a substrate sample that has undergone a chemical-mechanical polishing (CMP) process includes obtaining initial and terminating resistance and reactance measurements from the sample. Initial eddy current measurement values are obtained while an eddy current probe is positioned at an initial distance relative to the substrate sample, and terminating values are obtained while the eddy current probe is positioned at a modified distance relative to the sample. An intersecting line can be calculated using the initial and terminating resistance and reactance measurements. An intersecting point between a previously defined natural intercepting curve and the intersecting line may also be determined. A reactance voltage of the intersecting point may be located along a digital calibration curve to identify a closest-two of a plurality of calibration samples. The conductive top layer thickness of the substrate sample can then be determined by approximating a location, using linear or non-linear calculations, of the reactance voltage relative to the closest-two of the plurality of calibration samples.

US Patent:

6762604, Jul 13, 2004

Filed:

Apr 14, 2003

Appl. No.:

10/417048

Inventors:

Cuong Duy Le - Morgan Hill CA 98037

International Classification:

G01B 706

US Classification:

324230, 451 8, 702170

Abstract:

A standalone eddy current monitoring system provides a thickness profile of a substrate sample by obtaining initial and terminating resistance and reactance measurements from the sample. Initial eddy current measurement values are obtained while an eddy current probe is positioned at an initial distance relative to the substrate sample, and terminating values are obtained while the eddy current probe is positioned at a modified distance relative to the sample. An intersecting line can be calculated using the initial and terminating resistance and reactance measurements. An intersecting point between a previously defined natural intercepting curve and the intersecting line may also be determined. A reactance voltage of the intersecting point may be located along a digital calibration curve to identify a closest-two of a plurality of calibration samples. The conductive top layer thickness of the substrate sample can then be determined by approximating a location, using linear or non-linear calculations, of the reactance voltage relative to the closest-two of the plurality of calibration samples.

US Patent:

7019519, Mar 28, 2006

Filed:

Aug 24, 2004

Appl. No.:

10/924516

Inventors:

Cuong Duy Le - Morgan Hill CA, US

International Classification:

G01B 7/06
G01R 33/12

US Classification:

324230, 324229, 324225, 702104

Abstract:

A method for monitoring an inspection sample includes generating inspection data comprising resistance and reactance measurements that are obtained from an inspection sample having a conductive layer of unknown thickness. Calibration data is used for estimating the thickness of the conductive layer of the inspection sample. This calibration data includes resistance and reactance measurements obtained from one or more calibration samples, each calibration sample having a conductive layer of known thickness. The conductive layers of the inspection sample and the calibration samples comprise different materials having a known conductive relationship.

US Patent:

20030206008, Nov 6, 2003

Filed:

Apr 14, 2003

Appl. No.:

10/414845

Inventors:

Cuong Le - Gilroy CA, US

International Classification:

G01B007/06

US Classification:

324/230000

Abstract:

A method for estimating a thickness profile of a substrate sample that has undergone a physical vapor deposition (PVD) process includes obtaining initial eddy current measurement values while an eddy current probe is positioned at an initial distance relative to the substrate sample. Terminating values are obtained while the eddy current probe is positioned at a modified distance relative to the sample. An intersecting line can be calculated using the initial and terminating resistance and reactance measurements. An intersecting point between a previously defined natural intercepting curve and the intersecting line may also be determined. A reactance voltage of the intersecting point may be located along a digital calibration curve to identify a closest-two of a plurality of calibration samples. The conductive top layer thickness of the substrate sample can then be determined by approximating a location, using linear or non-linear calculations, of the reactance voltage relative to the closest-two of the plurality of calibration samples.

US Patent:

20030206009, Nov 6, 2003

Filed:

Apr 14, 2003

Appl. No.:

10/417046

Inventors:

Cuong Le - Gilroy CA, US

International Classification:

G01B007/06

US Classification:

324/230000

Abstract:

A system for monitoring a plurality of semiconductor fabrication systems includes a communication link between each of the semiconductor fabrication systems and the monitoring system. In operation, initial eddy current measurement values are obtained while an eddy current probe is positioned at an initial distance relative to the substrate sample, and terminating values are obtained while the eddy current probe is positioned at a modified distance relative to the sample. An intersecting line can be calculated using the initial and terminating resistance and reactance measurements. An intersecting point between a previously defined natural intercepting curve and the intersecting line may also be determined. A reactance voltage of the intersecting point may be located along a digital calibration curve to identify a closest-two of a plurality of calibration samples. The conductive top layer thickness of the substrate sample can then be determined by approximating a location, using linear or non-linear calculations, of the reactance voltage relative to the closest-two of the plurality of calibration samples.

US Patent:

20030210041, Nov 13, 2003

Filed:

Apr 14, 2003

Appl. No.:

10/414846

Inventors:

Cuong Le - Gilroy CA, US

International Classification:

G01B007/06

US Classification:

324/230000

Abstract:

A method for estimating a thickness profile of a substrate sample that has undergone a chemical vapor deposition (CVD) process includes obtaining initial eddy current measurement values while an eddy current probe is positioned at an initial distance relative to the substrate sample. Terminating values are obtained while the eddy current probe is positioned at a modified distance relative to the sample. An intersecting line can be calculated using the initial and terminating resistance and reactance measurements. An intersecting point between a previously defined natural intercepting curve and the intersecting line may also be determined. A reactance voltage of the intersecting point may be located along a digital calibration curve to identify a closest-two of a plurality of calibration samples. The conductive top layer thickness of the substrate sample can then be determined by approximating a location, using linear or non-linear calculations, of the reactance voltage relative to the closest-two of the plurality of calibration samples.