Dimensional Stability of Multilayer Circuit Boards

Numerical and experimental studies are performed to study residual deformation and warpage in a model multilayer circuit board construction of a common composite substrate (7628 fabric style). A numerical procedure based on classical lamination theory with non-isothermal viscoelastic constitutive relations is developed to predict the deformation and residual stress state due to relamination. Experimental values of the substrate stress relaxation modulus and coefficients of thermal expansion (CTE) are used as inputs in the numerical procedure to predict warpage of model circuit boards with a non-symmetric lay-up of 7628 style composite substrate. Boards with the exact same construction as used in the numerical analysis were fabricated according to the prescribed pressing cycle and the time dependent warpage measured using an ultrasonic contour scan technique. Comparison of the experimental warpage data with numerical predictions provides insight into the effects of processing cycle and substrate properties on residual stress development.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Theoretical and Applied Mechanics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Shrotriya, Pranav

Contributors dc:contributor

• Sottos, Nancy R.

• Engineering, Materials Science

Language dc:language

eng

Identifier

(MiAaPQ)AAI9996682

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/87777