Selective one-step plasma patterning process for fluidic self-assembly of silicon chips

Research output: Contribution to book/Conference proceedings/Anthology/ReportConference contributionContributedpeer-review

Contributors

  • Karlheinz Bock - , Chair of Electronic Packaging Technology, Fraunhofer Institute for Reliability and Microintegration (Author)
  • Sabine Scherbaum - , Fraunhofer Institute for Reliability and Microintegration (Author)
  • Erwin Yacoub-George - , Fraunhofer Institute for Reliability and Microintegration (Author)
  • Christof Landesberger - , Fraunhofer Institute for Reliability and Microintegration (Author)

Abstract

Applying a tetrafluoromethane (CF4) low pressure plasma process to the surface of a polymeric foil with a structured thin film copper layer on top results in an opposed wettability behavior of metal areas and polymer areas. Difference in the local water contact angle between the hydrophobic polymer and the hydrophilic copper after a maskless CF4 plasma treatment is 95° - 105°. By storing the plasma treated foils under nitrogen their programmed wetting behavior can be preserved for at least ten day. The special wetting properties of surface energy patterned foils favor them as substrate materials in fluidic self assembly processes. Self alignment of small and thin silicon chips on copper bonding sites on polyimide foils was observed. Specific design patterns are proposed that enable both bonding of dies at dedicated target positions and electrical interconnects at front side or rear side of electronic components with two connection pads. Using a droplet of water as assembly medium and an anisotropic conductive adhesive (ACA) coating lead to successfully assembled test chips on patterned polyimide foils that were pre-treated in the selective one-step CF4 plasma.

Details

Original languageEnglish
Title of host publication2008 Proceedings 58th Electronic Components and Technology Conference, ECTC
Pages1099-1104
Number of pages6
Publication statusPublished - 2008
Peer-reviewedYes

Publication series

SeriesElectronic Components and Technology Conference (ECTC)
ISSN0569-5503

Conference

Title2008 58th Electronic Components and Technology Conference
Abbreviated titleECTC 2008
Conference number58
Duration27 - 30 May 2008
CityLake Buena Vista
CountryUnited States of America

External IDs

ORCID /0000-0002-0757-3325/work/139064816