Micro-structural studies of thermosonic Cu-Al bonding interface

T. Joseph Sahaya Anand, Chua Kok Yau, Azman Jalar @ Jalil

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Thermosonic Copper (Cu) wire interconnection has been under an extensive research and development to replace expensive Gold (Au) wire material in the semiconductor industry. However, a reliability concern is raised due to void formation at the bonding interface of Copper wire- Aluminum bond pad (Cu-Al) after High Temperature Storage (HTS) annealing condition. It is believed that the Intermetallic Compound (IMC) layer growth and evolution lead to a volumetric shrinkage which in turn results in the void formation. Annealing conditions influence the development of the IMC at the bonding interface which is related to the bonding reliability. In this work, the effects of annealing toward the micro-structure and IMC growth at the bonding interface were evaluated using Scanning Transmission Electron Microscope equipped with Energy Dispersive X-ray analysis. In the as-synthesized sample bonded at 100°C, an inhomogeneous IMC formation dominated by grain boundary diffusion was observed. After High Temperature Storage of 1000 hours, the consumption of the Al bond pad resulted in the formation of irregular IMC layers. The variation of phases existed in a localized region was believed due to simultaneous growth of IMC by both grain boundary and volume diffusions. Moreover, the diffusion of Cu into Si was observed. This resulted in the formation of the mixture of Si + η" phases in the affected sea region.

Original languageEnglish
Title of host publicationAdvanced Materials Research
PublisherTrans Tech Publications
Pages154-158
Number of pages5
Volume925
ISBN (Print)9783038350866
DOIs
Publication statusPublished - 2014
EventJoint International Conference on Nanoscience, Engineering and Management, BOND21 - Penang
Duration: 19 Aug 201321 Aug 2013

Publication series

NameAdvanced Materials Research
Volume925
ISSN (Print)10226680

Other

OtherJoint International Conference on Nanoscience, Engineering and Management, BOND21
CityPenang
Period19/8/1321/8/13

Fingerprint

Intermetallics
Wire
Annealing
Grain boundaries
Copper
Energy dispersive X ray analysis
Electron microscopes
Gold
Semiconductor materials
Scanning
Aluminum
Temperature
Microstructure
Industry

Keywords

  • Cu-Al intermetallics
  • High temperature storage
  • Thermosonic
  • Void formation

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Anand, T. J. S., Kok Yau, C., & Jalar @ Jalil, A. (2014). Micro-structural studies of thermosonic Cu-Al bonding interface. In Advanced Materials Research (Vol. 925, pp. 154-158). (Advanced Materials Research; Vol. 925). Trans Tech Publications. https://doi.org/10.4028/www.scientific.net/AMR.925.154

Micro-structural studies of thermosonic Cu-Al bonding interface. / Anand, T. Joseph Sahaya; Kok Yau, Chua; Jalar @ Jalil, Azman.

Advanced Materials Research. Vol. 925 Trans Tech Publications, 2014. p. 154-158 (Advanced Materials Research; Vol. 925).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Anand, TJS, Kok Yau, C & Jalar @ Jalil, A 2014, Micro-structural studies of thermosonic Cu-Al bonding interface. in Advanced Materials Research. vol. 925, Advanced Materials Research, vol. 925, Trans Tech Publications, pp. 154-158, Joint International Conference on Nanoscience, Engineering and Management, BOND21, Penang, 19/8/13. https://doi.org/10.4028/www.scientific.net/AMR.925.154
Anand TJS, Kok Yau C, Jalar @ Jalil A. Micro-structural studies of thermosonic Cu-Al bonding interface. In Advanced Materials Research. Vol. 925. Trans Tech Publications. 2014. p. 154-158. (Advanced Materials Research). https://doi.org/10.4028/www.scientific.net/AMR.925.154
Anand, T. Joseph Sahaya ; Kok Yau, Chua ; Jalar @ Jalil, Azman. / Micro-structural studies of thermosonic Cu-Al bonding interface. Advanced Materials Research. Vol. 925 Trans Tech Publications, 2014. pp. 154-158 (Advanced Materials Research).
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