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oai:www.ideals.illinois.edu:2142/82738 2023-07-11 col_2142_5131 col_2142_13836 com_2142_5130 com_2142_13835 com_2142_234

Payne, David A. Mikalsen, Erik Arthur 2015-09-25T20:52:46Z 2015-09-25T20:52:46Z 10000-01-01 2003 2003 The shrinkage and densification of sol-gel layers were determined by in-situ and ex-situ measurements, where a &sim;30% decrease in thickness (t) was typical during drying of sol-gel layers (T < 300&deg;C). Constrained shrinkage, resulting from adhesion to the supporting silicon substrate, led to a coherent (crack-free) film with biaxial stresses of &sim;200 MPa (t &sim; 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. Made available in DSpace on 2015-09-25T20:52:46Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 3086141.pdf: 13293065 bytes, checksum: cc2603ed63c917994ce35828b1574c5c (MD5) Previous issue date: 2003 Embargo set by: Seth Robbins for item 84019 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 231 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2003. http://hdl.handle.net/2142/82738 (MiAaPQ)AAI3086141 eng Engineering, Materials Science Mediated Patterning of Sol -Gel Thin Layers: Shrinkage, Decohesion, and Lift-Off text Materials Science and Engineering Materials Science and Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.