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Title: Surface Profile and Stress Field Evaluation using Digital Gradient Sensing Method

Abstract

Shape and surface topography evaluation from measured orthogonal slope/gradient data is of considerable engineering significance since many full-field optical sensors and interferometers readily output accurate data of that kind. This has applications ranging from metrology of optical and electronic elements (lenses, silicon wafers, thin film coatings), surface profile estimation, wave front and shape reconstruction, to name a few. In this context, a new methodology for surface profile and stress field determination based on a recently introduced non-contact, full-field optical method called digital gradient sensing (DGS) capable of measuring small angular deflections of light rays coupled with a robust finite-difference-based least-squares integration (HFLI) scheme in the Southwell configuration is advanced here. The method is demonstrated by evaluating (a) surface profiles of mechanically warped silicon wafers and (b) stress gradients near growing cracks in planar phase objects.

Authors:
 [1];  [1];  [2];  [1]
  1. Auburn Univ., AL (United States)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1340426
Report Number(s):
BNL-113341-2016-JA
Journal ID: ISSN 0957-0233
Grant/Contract Number:
SC00112704
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Measurement Science and Technology
Additional Journal Information:
Journal Volume: 27; Journal ID: ISSN 0957-0233
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; Optical Metrology; Surface Slopes; Stress Gradients; Digital Gradient Sensing; Surface Topography; Stress Evaluation

Citation Formats

Miao, C., Sundaram, B. M., Huang, L., and Tippur, H. V. Surface Profile and Stress Field Evaluation using Digital Gradient Sensing Method. United States: N. p., 2016. Web. doi:10.1088/0957-0233/27/9/095203.
Miao, C., Sundaram, B. M., Huang, L., & Tippur, H. V. Surface Profile and Stress Field Evaluation using Digital Gradient Sensing Method. United States. doi:10.1088/0957-0233/27/9/095203.
Miao, C., Sundaram, B. M., Huang, L., and Tippur, H. V. 2016. "Surface Profile and Stress Field Evaluation using Digital Gradient Sensing Method". United States. doi:10.1088/0957-0233/27/9/095203. https://www.osti.gov/servlets/purl/1340426.
@article{osti_1340426,
title = {Surface Profile and Stress Field Evaluation using Digital Gradient Sensing Method},
author = {Miao, C. and Sundaram, B. M. and Huang, L. and Tippur, H. V.},
abstractNote = {Shape and surface topography evaluation from measured orthogonal slope/gradient data is of considerable engineering significance since many full-field optical sensors and interferometers readily output accurate data of that kind. This has applications ranging from metrology of optical and electronic elements (lenses, silicon wafers, thin film coatings), surface profile estimation, wave front and shape reconstruction, to name a few. In this context, a new methodology for surface profile and stress field determination based on a recently introduced non-contact, full-field optical method called digital gradient sensing (DGS) capable of measuring small angular deflections of light rays coupled with a robust finite-difference-based least-squares integration (HFLI) scheme in the Southwell configuration is advanced here. The method is demonstrated by evaluating (a) surface profiles of mechanically warped silicon wafers and (b) stress gradients near growing cracks in planar phase objects.},
doi = {10.1088/0957-0233/27/9/095203},
journal = {Measurement Science and Technology},
number = ,
volume = 27,
place = {United States},
year = 2016,
month = 8
}

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Free Publicly Available Full Text
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