Unsteady Wire Sweep Due to Transfer Molding in a 160L QFP Package

[+] Author and Article Information
H. Chai, Y. Zohar

Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong

J. Electron. Packag 121(2), 127-134 (Jun 01, 1999) (8 pages) doi:10.1115/1.2792668 History: Received December 08, 1998; Revised February 24, 1999; Online November 05, 2007


Wire sweep has been recognized as one of the major defects in encapsulation of electronic components by transfer molding. The phenomenon is very complicated as it is sensitive to a large number of parameters. In this experimental work, where a 160L QFP package used as the test vehicle, the detailed time-dependent wire displacement is measured for the following two different flow initial conditions: (i) the wire is immersed in the liquid and is displaced due to the acceleration of the flow from rest to the steady-state velocity, and (ii) the wire is surrounded by the ambient air and is displaced first due to the passage of the liquid front and then due to the hydrodynamic load. Significant differences have been observed between the two cases, with important implications for analytical and numerical studies of wire sweep.

Copyright © 1999 by The American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.





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 Journal Articles
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