Masters Theses

Abstract

"This thesis is to characterize the thin membrane adhesion-delamination phenomena which occur in biological cells and micro-electro-mechanical systems (MEMS) operation. The delamination of a thin film adhered to a rigid substrate is subjected to the coupling effects of tensile residual stress and interfacial adhesion energy. The adhesion-delamination mechanics is derived using the classical linear elasticity and thermodynamics energy balance. The membrane deformation is here dominated by a mixed plate-bending and membrane-stretching, while the concomitant stress is neglected. An 1-dimensional model is first investigated where a pre-stressed rectangular film clamped at both ends delaminates from a rigid punch of the same dimension as the film width. Upon a tensile external load applied to the rigid punch, "Pinch-off", or stable shrinking of the contact area to a line prior to complete detachment, is predicted. The 1-dimensional model is further extended to a 2-dimensional axisymmetric geometry. A thin circular film clamped at the periphery detaches from the planar surface of a rigid cylindrical punch upon external load. "Pull-off", or spontaneous detachment from the substrate, occurs when the contact circle shrinks to between 0.1758 and 0.3651 times the film radius depending on the magnitude of the residual membrane stress. The finite "pulloff" radius differs from the 1-dimensional counterpart. The models are useful in understanding the behavior of various adhesion-delamination phenomena, such as capacitive MEMS-RF switches, micro pumps, microstructure network, and nanostructures"--Abstract, page iii.

Advisor(s)

Wan, Kai-Tak

Committee Member(s)

Kim, Chang-Soo
Miller, Brad A.

Department(s)

Mechanical and Aerospace Engineering

Degree Name

M.S. in Mechanical Engineering

Sponsor(s)

National Science Foundation (U.S.)
University of Missouri Research Board

Comments

Appendix A (thesis pages 41-47) "Adhesion-delamination mechanics of a prestressed rectangular film adhered onto a rigid substrate." Journal of Applied Physics 101.2 (2007):024903.
Appendix B (thesis pages 49-65) "Adhesion-delamination mechanics of a prestressed circular film adhered onto a rigid substrate." The Journal of Adhesion 83.1 (2007):67-83.
Appendix D (thesis pages 73-78) "A novel cylindrical punch method to characterize interfacial adhesion and residual stress of a thin polymer film." Engineering Fracture Mechanics 74.7 (2007):1,101-1, 106.

Publisher

University of Missouri--Rolla

Publication Date

Summer 2007

Pagination

x, 52 pages

Note about bibliography

Includes bibliographical references (pages 21-23).

Rights

© 2007 Ming-Fung Wong, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Subject Headings

Adhesion
Composite materials -- Delamination
Microelectromechanical systems
Thin films

Thesis Number

T 9244

Print OCLC #

378731370

Electronic OCLC #

808631739

Download

Share

 
COinS