A fracture mechanics methodology for slow crack growth in thin polyimide films

Author

Kenner, Vemal H. ; Popelar, Scott F. ; Popelar, Carl H.

Author_Institution

Dept. of Eng. Mech., Ohio State Univ., Columbus, OH, USA

fYear

1991

fDate

12-14 Jun 1991

Firstpage

242

Lastpage

245

Abstract

A fracture mechanics methodology for assessing the influence of stress and defect size on the structural integrity and life expectancy of thin polyimide films is presented. The approach is a synergistic one that combines fracture mechanics analyses and experiments to quantify slow crack in the films. A viscoelastic fracture model is used to deduce the crack growth history from load-point displacement records measured during long-term fracture tests of the films. The rate of crack growth is found to depend very strongly upon the crack driving force as measured by the stress intensity factor. Hence, small changes in the stress intensity factor can produce dramatic changes in the crack growth rate in the materials investigated

Keywords

encapsulation; fracture toughness testing; polymer films; reliability; crack driving force; crack growth history; crack growth rate; defect size influence; fracture mechanics analyses; fracture mechanics methodology; life expectancy; load-point displacement records; long-term fracture tests; polyimide films; slow crack growth; stress influence; stress intensity factor; structural integrity; viscoelastic fracture model; Differential equations; Elasticity; History; Polyimides; Power demand; Residual stresses; Temperature; Testing; Thermal stresses; Viscosity;

fLanguage

English

Publisher

ieee

Conference_Titel

University/Government/Industry Microelectronics Symposium, 1991. Proceedings., Ninth Biennial

Conference_Location

Melbourne, FL

ISSN

0749-6877

Print_ISBN

0-7803-0109-9

Type

conf

DOI

10.1109/UGIM.1991.148158

Filename

148158