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Title: Eddy Current Testing for Detecting Small Defects in Thin Films

Abstract

Presented here is a technique of using Eddy Current based Giant Magneto-Resistance sensor (GMR) to detect surface and sub-layered minute defects in thin films. For surface crack detection, a measurement was performed on a copper metallization of 5-10 microns thick. It was done by scanning the GMR sensor on the surface of the wafer that had two scratches of 0.2 mm, and 2.5 mm in length respectively. In another experiment, metal coatings were deposited over the layers containing five defects with known lengths such that the defects were invisible from the surface. The limit of detection (resolution), in terms of defect size, of the GMR high-resolution Eddy Current probe was studied using this sample. Applications of Eddy Current testing include detecting defects in thin film metallic layers, and quality control of metallization layers on silicon wafers for integrated circuits manufacturing.

Authors:
;  [1];  [2]
  1. Electrical and Computer Engineering Department, UNCC (United States)
  2. Albany Instruments, 426-O Barton Creek, Charlotte, NC 28262 (United States)
Publication Date:
OSTI Identifier:
21054969
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 894; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Portland, OR (United States), 30 Jul - 4 Aug 2006; Other Information: DOI: 10.1063/1.2717992; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COATINGS; COPPER; CRACKS; DEFECTS; DETECTION; EDDY CURRENT TESTING; EDDY CURRENTS; INTEGRATED CIRCUITS; LAYERS; MAGNETORESISTANCE; QUALITY CONTROL; RESOLUTION; SENSORS; SILICON; SURFACES; THIN FILMS

Citation Formats

Obeid, Simon, Tranjan, Farid M., and Dogaru, Teodor. Eddy Current Testing for Detecting Small Defects in Thin Films. United States: N. p., 2007. Web. doi:10.1063/1.2717992.
Obeid, Simon, Tranjan, Farid M., & Dogaru, Teodor. Eddy Current Testing for Detecting Small Defects in Thin Films. United States. doi:10.1063/1.2717992.
Obeid, Simon, Tranjan, Farid M., and Dogaru, Teodor. Wed . "Eddy Current Testing for Detecting Small Defects in Thin Films". United States. doi:10.1063/1.2717992.
@article{osti_21054969,
title = {Eddy Current Testing for Detecting Small Defects in Thin Films},
author = {Obeid, Simon and Tranjan, Farid M. and Dogaru, Teodor},
abstractNote = {Presented here is a technique of using Eddy Current based Giant Magneto-Resistance sensor (GMR) to detect surface and sub-layered minute defects in thin films. For surface crack detection, a measurement was performed on a copper metallization of 5-10 microns thick. It was done by scanning the GMR sensor on the surface of the wafer that had two scratches of 0.2 mm, and 2.5 mm in length respectively. In another experiment, metal coatings were deposited over the layers containing five defects with known lengths such that the defects were invisible from the surface. The limit of detection (resolution), in terms of defect size, of the GMR high-resolution Eddy Current probe was studied using this sample. Applications of Eddy Current testing include detecting defects in thin film metallic layers, and quality control of metallization layers on silicon wafers for integrated circuits manufacturing.},
doi = {10.1063/1.2717992},
journal = {AIP Conference Proceedings},
number = 1,
volume = 894,
place = {United States},
year = {Wed Mar 21 00:00:00 EDT 2007},
month = {Wed Mar 21 00:00:00 EDT 2007}
}
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