Paul R Unruh

US Patent:

6552806, Apr 22, 2003

Filed:

Feb 3, 2000

Appl. No.:

09/497567

Inventors:

Richard W. Swinford - Tucson AZ
David J. Aziz - Tucson AZ
Bryan W. Guenther - Tucson AZ
Paul R. Unruh - Tucson AZ

Assignee:

Veeco Instruments Inc. - Tucson AZ

International Classification:

G01B 902

US Classification:

356512, 356497

Abstract:

Average fringe contrast is determined by PSI measurements at each step of relatively large translations of the reference optics and mirror of a white-light Linnik interference objective and the resulting data are used to minimize the OPD between the reference and test beam paths of the instrument. Utilizing the same algorithms used in the art to perform conventional vertical scanning interferometry, the position of minimum OPD is determined by finding the position of maximum average fringe contrast. Furthermore, by automating the system with a precise translation mechanism, operator-to-operator variations are completely eliminated and the precision of the process of OPD minimization is greatly improved. In another embodiment of the invention, the optimal focal position of the reference mirror is found at the same time by calculating the average lateral variation of fringe contrast as a function of OPD and focal position. The optimal OPD and focal position correspond to the maximum average lateral variation of fringe contrast in the resulting three-dimensional space.

US Patent:

7119909, Oct 10, 2006

Filed:

Jun 16, 2004

Appl. No.:

10/869138

Inventors:

Paul R. Unruh - Oro Valley AZ, US
Joanna Schmit - Tucson AZ, US
Erik L. Novak - Tucson AZ, US

Assignee:

Veeco Instruments, Inc. - Tucson AZ

International Classification:

G01B 9/02
G01B 11/28

US Classification:

356504, 356630

Abstract:

Two threshold parameters are used to identify the intensity modulation peaks corresponding to the interfaces of the two sides of a thin film with the adjacent media. The first parameter is used to distinguish modulation data from noise and is set on the basis of actual background noise data measured during the interferometric scan. The second parameter is used to separate actual contrast data from signals of relatively high modulation that satisfy the first parameter but do not in fact result from interference fringes. Data that satisfy both parameters are considered valid modulation data and the peak of each modulation envelope is then calculated using conventional means. The thickness of the film at each pixel is obtained by dividing the scanning distance corresponding to the two peaks by the group index of refraction of the film material.

US Patent:

7283250, Oct 16, 2007

Filed:

Jan 16, 2004

Appl. No.:

10/759686

Inventors:

Joanna Schmit - Tucson AZ, US
Paul R. Unruh - Oro Valley AZ, US
Erik L. Novak - Tucson AZ, US

Assignee:

Veeco Instruments, Inc. - Tucson AZ

International Classification:

G01B 9/02

US Classification:

356512, 356495

Abstract:

An interferometric profiler is used to measure object motion by modifying the motion of the scanner so that the phase variation at each scanning step is kept within the acceptable limits of the algorithm used to calculate phase changes. The scanner motion is so manipulated on the basis of prior knowledge about the nature of the object motion, or knowledge obtained by pre-calibration, or by real-time feedback based on current measurements. The object motion is recovered from the scanning information by subtracting the scanner position from the object position as it evolves during the scan.

US Patent:

20120265487, Oct 18, 2012

Filed:

May 19, 2011

Appl. No.:

13/111789

Inventors:

Emilio Yanine - Tucson AZ, US
Paul R. Unruh - Oro Valley AZ, US
Michael B. Krell - Tucson AZ, US
Son H. Bui - Tucson AZ, US
Joseph P. Moore - Tucson AZ, US
Dmitriy K. Kiselev - Tucson AZ, US
Ross O. Smith - Palo Alto CA, US

International Classification:

G06F 15/00
G01B 21/20

US Classification:

702168, 702167

Abstract:

An improved apparatus and method for the analysis of surface data collected using a sub-micron scale metrology instrument which provides a persistent user experience by allocating set portions of the display to major functional regions thereby allowing a quick to learn and easy to user interface for the setup, analysis, and display of microscopic 3D surface data measurements and resulting analytic data with a variety of 3D surface scanners.

US Patent:

57267545, Mar 10, 1998

Filed:

Aug 30, 1996

Appl. No.:

8/697865

Inventors:

Michael P. Andrews - Tucson AZ
Paul R. Unruh - Tucson AZ

Assignee:

Wyko Corporation - Tucson AZ

International Classification:

G01B 902

US Classification:

356357

Abstract:

A method of operation of a scanning mechanism that produces multiple constant-speed translations within the scanning range of operation. According to one aspect of the invention, when the instrument translates over a region where useful fringes are substantially absent, such as over the steep portion of a step discontinuity, the scanner is quickly accelerated to a higher constant speed and collection of intensity data is stopped until it reaches a new region of observable fringes. The scanner then is quickly decelerated to a slower constant speed and acquisition of intensity data resumes. According to another aspect of the invention, the position of the scanner during the nonlinear transition between regions of different constant speeds is determined by applying a transition factor based on the rate of acceleration (or deceleration) during the transition period. A practical transition factor is advantageously determined by assuming constant acceleration (or deceleration) during each transition between periods of constant-speed operation.