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Title: Nondestructive Evaluation of Submicron Delaminations at Polymer/Metal Interface in Flex Circuits

Abstract

The dimensions of the defects in micro-electronic components have reached the resolution limit of many traditional quality control instruments. As the sizes of the components are reaching a few hundred microns, the life of the components will be limited by defects of submicron dimensions. In this regard, there is a need for development of new NDE techniques to detect submicron defects. In this paper we examine the use of combined Atomic Force Microscopy (AFM) and Ultrasonic Force Microscopy (UFM) to evaluate submicron and nanometer size delaminations at the polymer-metal interface of a flex circuit. Surface topography images obtained using atomic force microscopy is compared with ultrasonic force microscopy images obtained on the same region of the flex circuits. The contrast in the UFM images show detailed features of delaminations present at the polymer/metal interface. It also reveals the microstructure of copper sandwiched between two polymer layers. Experiments were performed to image the growth and evolution of delaminations while a constant current is passed through the copper conductor. Results of microstructure of copper through a polymer layer and growth of delaminations are presented. The role of the two microscopes as a quality-control tool in micro-electronics and computer industries is discussed.

Authors:
;  [1];  [2]
  1. Center for Materials Diagnostics, University of Dayton Research Institute, Dayton, OH 45469 (United States)
  2. Seagate Technology, 7801 Computer Avenue South, Bloomington, MN 55435-5489 (United States)
Publication Date:
OSTI Identifier:
20798239
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 820; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Brunswick, ME (United States), 31 Jul - 5 Aug 2005; Other Information: DOI: 10.1063/1.2184708; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ACOUSTIC MICROSCOPY; ATOMIC FORCE MICROSCOPY; COPPER; DEFECTS; IMAGES; INTERFACES; NONDESTRUCTIVE ANALYSIS; NONDESTRUCTIVE TESTING; POLYMERS; QUALITY CONTROL

Citation Formats

Nalladega, Vijayaraghava, Sathish, Shamachary, and Brar, Amarjit S. Nondestructive Evaluation of Submicron Delaminations at Polymer/Metal Interface in Flex Circuits. United States: N. p., 2006. Web. doi:10.1063/1.2184708.
Nalladega, Vijayaraghava, Sathish, Shamachary, & Brar, Amarjit S. Nondestructive Evaluation of Submicron Delaminations at Polymer/Metal Interface in Flex Circuits. United States. doi:10.1063/1.2184708.
Nalladega, Vijayaraghava, Sathish, Shamachary, and Brar, Amarjit S. Mon . "Nondestructive Evaluation of Submicron Delaminations at Polymer/Metal Interface in Flex Circuits". United States. doi:10.1063/1.2184708.
@article{osti_20798239,
title = {Nondestructive Evaluation of Submicron Delaminations at Polymer/Metal Interface in Flex Circuits},
author = {Nalladega, Vijayaraghava and Sathish, Shamachary and Brar, Amarjit S.},
abstractNote = {The dimensions of the defects in micro-electronic components have reached the resolution limit of many traditional quality control instruments. As the sizes of the components are reaching a few hundred microns, the life of the components will be limited by defects of submicron dimensions. In this regard, there is a need for development of new NDE techniques to detect submicron defects. In this paper we examine the use of combined Atomic Force Microscopy (AFM) and Ultrasonic Force Microscopy (UFM) to evaluate submicron and nanometer size delaminations at the polymer-metal interface of a flex circuit. Surface topography images obtained using atomic force microscopy is compared with ultrasonic force microscopy images obtained on the same region of the flex circuits. The contrast in the UFM images show detailed features of delaminations present at the polymer/metal interface. It also reveals the microstructure of copper sandwiched between two polymer layers. Experiments were performed to image the growth and evolution of delaminations while a constant current is passed through the copper conductor. Results of microstructure of copper through a polymer layer and growth of delaminations are presented. The role of the two microscopes as a quality-control tool in micro-electronics and computer industries is discussed.},
doi = {10.1063/1.2184708},
journal = {AIP Conference Proceedings},
number = 1,
volume = 820,
place = {United States},
year = {Mon Mar 06 00:00:00 EST 2006},
month = {Mon Mar 06 00:00:00 EST 2006}
}
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