Analysis of TAB inner lead fatigue in thermal cycle environments

Author

Cluff, Kevin D.

Author_Institution

Honeywell Inc., Phoenix, AZ, USA

fYear

1994

fDate

1-4 May 1994

Firstpage

474

Lastpage

481

Abstract

The inner leads of a Tape Automated Bonding (TAB) device can be subject to early fatigue failures in thermal cycle environments. This paper describes a 3-D non-linear finite element analysis of the failure mechanism, and verifies the results by experiment. Some TAB applications require environmental qualification and electrical testing in the unexcised tape carrier or retain a significant portion of the polyimide tape in the assembly. In these cases the Coefficient of Thermal Expansion (CTE) mismatch between the silicon die and polyimide tape can cause plastic strains in the inner leads. Several design variations are quantified. Those with first order effects were found to be encapsulant material, lead length, and lead material

Keywords

Weibull distribution; encapsulation; failure (mechanical); fatigue; finite element analysis; lead bonding; tape automated bonding; thermal expansion; 3D nonlinear finite element analysis; CTE mismatch; TAB inner lead fatigue; encapsulant material; failure mechanism; fatigue failures; lead length; lead material; plastic strains; thermal cycle environments; unexcised tape carrier; Assembly; Bonding; Failure analysis; Fatigue; Finite element methods; Polyimides; Qualifications; Silicon; Testing; Thermal expansion;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Components and Technology Conference, 1994. Proceedings., 44th

Conference_Location

Washington, DC

Print_ISBN

0-7803-0914-6

Type

conf

DOI

10.1109/ECTC.1994.367550

Filename

367550