Journal of Electronic Materials

, Volume 19, Issue 12, pp 1345–1350

PCB glass-fibre laminates: Thermal conductivity measurements and their effect on simulation

  • F. Sarvar
  • N. J. Poole
  • P. A. Witting
Article

Abstract

Accurate values of thermal conductivity are required for the simulation of temperature phenomena in electronic circuits. This paper presents the results of measurements carried out to determine the thermal conductivity along and normal to the plane of fibre glass laminates used in the manufacture of printed circuit boards. It has been found that the reinforced fibre-glass substrates used in PCBs are strongly anisotropic with the conductivity normal to the boards being much smaller than tangential to it. The test samples were type FR4 epoxy/glass laminates. An experiment has been designed which determines the thermal conductivity in-the-plane of the laminates by matching the measured temperature distribution along a heated specimen with a finite difference solution. An electrically heated Lees’ disc apparatus is also used to measure the thermal conductivity of these boards in a direction normal to their plane. The samples tested yielded values of 0.343 W/mK and 1.059 W/mK for thermal conductivity through and along the plane of the boards, respectively.

Key words

Thermal conductivity PCB substrate glass-fibre 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    HEIMANN Radiation Thermometer KT14 Instruction Manual, HEIMANN GmbH, Infrared Measurements, D-6200 Wiesbaden-Dotzheim, West Germany.Google Scholar
  2. 2.
    N. J. Poole, F. Sarvar, P. A. Witting and W. H. McKenzie, Int. J. Numerical Modelling1, 103 (1988).CrossRefGoogle Scholar
  3. 3.
    private communication, Mica and Micanite (Ireland) LTD., Mallow, Co. Cork, Ireland.Google Scholar
  4. 4.
    F. J. Bayley, J. M. Owen and A. B. Turner, Heat Transfer, Nelson and Sons Ltd., (1972), pp. 90–92.Google Scholar
  5. 5.
    ‘Nextel 2010 Velvet Coating’ Product Performance Bulletin and Application Instructions, 3M Industrial Chemical Products, 3M Head Office, Bracknell, Berks, England.Google Scholar
  6. 6.
    A. J. Chapman, Heat Transfer, 4th Ed., McGraw-Hill, New York, (1984), p. 131.Google Scholar
  7. 7.
    G. W. C. Kay and T. H. Laby, Tables of Physics and Chemical Constants, 15th Ed., Longman Group Ltd., (1986), p. 69.Google Scholar
  8. 8.
    A. J. Starling and A. J. Woodall, Physics, 2nd Ed. Longmans (1964), pp. 320–321.Google Scholar
  9. 9.
    Equipment Notes No. P28030/1 for Lees’ Disc Apparatus from Philip Harris Limited, Shenstone, England.Google Scholar
  10. 10.
    Data Sheet No. PD4/7/82, Polypenco Engineering Plastics Materials Limited, 76 Bridge Road East, Welwyn Garden City, Herts, England.Google Scholar

Copyright information

© The Mineral,Metal & Materials Society,Inc. 1990

Authors and Affiliations

  • F. Sarvar
    • 1
  • N. J. Poole
    • 1
  • P. A. Witting
    • 1
  1. 1.Department of Electronics and Information TechnologyPolytechnic of Wales, PontypriddMid GlamorganUK

Personalised recommendations