Full Content is available to subscribers

Subscribe/Learn More  >

Experimental Study of the High Cycle Fatigue of Thin Film Metal on Polyethylene Terephthalate for Flexible Electronics Applications

[+] Author Affiliations
Khalid Alzoubi, Susan Lu, Bahgat Sammakia

Binghamton University, State University of New York, Binghamton, NY

Mark Poliks

Endicott Interconnect Technologies, Endicott, NY

Paper No. InterPACK2009-89247, pp. 27-32; 6 pages
  • ASME 2009 InterPACK Conference collocated with the ASME 2009 Summer Heat Transfer Conference and the ASME 2009 3rd International Conference on Energy Sustainability
  • ASME 2009 InterPACK Conference, Volume 1
  • San Francisco, California, USA, July 19–23, 2009
  • Conference Sponsors: Electronic and Photonic Packaging Division
  • ISBN: 978-0-7918-4359-8 | eISBN: 978-0-7918-3851-8
  • Copyright © 2009 by ASME


Flexible electronics represent an emerging area in the electronics packaging and systems integration industry with the potential for new product development and commercialization in the near future. Manufacturing electronics on flexible substrates will produce low cost devices that are rugged, light, and flexible. However, electronic systems are vulnerable to failures caused by mechanical and thermal stresses. For electronic systems on flexible substrates repeated stresses below the ultimate tensile strength or even below the yield strength will cause failures in the thin films. It is known that mechanical properties of thin films are different from those of bulk materials; so, it is difficult to extrapolate bulk material properties on thin film materials. The objective of this work is to study the behavior of thin-film metal coated flexible substrates under high cyclic bending fatigue loading. Polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) are widely used substrates in the fabrication of microelectronic devices. Factors affecting the fatigue life of thin-film coated flexible substrates were studied, including thin film thickness, temperature, and humidity. A series of experiments for sputter-deposited copper on PET substrates were performed. Electrical resistance and crack growth rate were monitored during the experiments at specified time intervals. High magnification images were obtained to observe the crack initiation and propagation in the metal film. Statistical analysis based on design of experiments concepts was performed to identify the main factors and factor’s interaction that affect the life of a thin-film coated substrate. The results of the experiments showed that the crack starts in the middle of the sample and slowly grows toward the edges. Electrical resistance increases slightly during the test until the crack length covers about 90% of the total width of the sample where a dramatic increase in the resistance takes place.

Copyright © 2009 by ASME



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In