Files in this item
Files | Description | Format |
---|---|---|
application/pdf ![]() ![]() | (no description provided) |
Description
Title: | Mediated Patterning of Sol -Gel Thin Layers: Shrinkage, Decohesion, and Lift-Off |
Author(s): | Mikalsen, Erik Arthur |
Doctoral Committee Chair(s): | Payne, David A. |
Department / Program: | Materials Science and Engineering |
Discipline: | Materials Science and Engineering |
Degree Granting Institution: | University of Illinois at Urbana-Champaign |
Degree: | Ph.D. |
Genre: | Dissertation |
Subject(s): | Engineering, Materials Science |
Abstract: | The shrinkage and densification of sol-gel layers were determined by in-situ and ex-situ measurements, where a ∼30% decrease in thickness (t) was typical during drying of sol-gel layers (T < 300°C). Constrained shrinkage, resulting from adhesion to the supporting silicon substrate, led to a coherent (crack-free) film with biaxial stresses of ∼200 MPa (t ∼ 50 nm). For ODTS-mediated sol-gel films, however, precise in-situ wafer curvature measurements determined that film stresses never exceeded 75 MPa. Additionally, interfacial adhesive strength between the substrate and the sol-gel film were evaluated for the first time using a unique pulsed-laser stress-wave technique. An adhesive strength threshold of 15 MPa was determined for sol-gel films on ODTS-functionalized silicon, whereas, the threshold strength of films deposited on unmodified silicon was determined as >25 MPa and greater than the fracture strength of silicon. In this work, hydrophobic surface regions, facilitated by directed mu-CP of a molecular film, affected adhesion so as to reduce the substrate constraint and promote de-cohesion of the sol-gel film on the sub-micron scale. That is, selective de-cohesion and lift-off were enabled by the control of local mechanical interfacial constraints. |
Issue Date: | 2003 |
Type: | Text |
Language: | English |
Description: | 231 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2003. |
URI: | http://hdl.handle.net/2142/82738 |
Other Identifier(s): | (MiAaPQ)AAI3086141 |
Date Available in IDEALS: | 2015-09-25 |
Date Deposited: | 2003 |
This item appears in the following Collection(s)
-
Dissertations and Theses - Materials Science and Engineering
-
Graduate Dissertations and Theses at Illinois
Graduate Theses and Dissertations at Illinois