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Birnbaum, Howard K. Peddada, Satyanarayana Rao 2011-05-07T13:20:31Z 2011-05-07T13:20:31Z 10000-01-01 1991 The aim of this research program was to understand the effect of thermal cycling on metal/insulator (sapphire and polyimide, PI) thin film laminates through studies of microstructure and microchemistry. Systems studied were: Ti/sapphire, Au/Cu/Ti/PI/Si and Cr/Cu/Cr/PI/Si. In the Ti/sapphire system, there was an additional interest to understand the effect of growth temperature on growth orientation and crystal quality of the films. The three material systems were characterized by a number of analytical techniques such as cross-section TEM (XTEM), plan-view TEM, SEM, Auger Electron Spectroscopy and X-ray diffraction. Of these, XTEM was the most extensively used. In the Ti/sapphire system, single crystals formed in the temperature range 245-750$\sp\circ$C with the respective close packed planes and directions parallel. The crystal quality improved with an increase in the growth temperature up to 750$\sp\circ$C. The interface was observed to be sharp with no reaction layer formation even at a growth temperature of 950$\sp\circ$C. On annealing in D$\sb2$ gas at 325$\sp\circ$C for 48 hours, the Ti film transformed to TiD$\sb2,$ but no mechanical failures were observed. In the Ti/PI system, on annealing in D$\sb2$ gas at 325$\sp\circ$C for 48 hours, the interface remained sharp to a large extent, but a discontinuous reaction zone consisting of an oxide, $\rm Ti\sb5O\sb9,$ formed at the interface due to a reaction between Ti and moisture in the PI. On annealing in D$\sb2$ gas, spontaneous edge delamination was observed at the Ti/PI interface. There was no extensive diffusion of Ti or Cu into PI even in samples annealed at 400$\sp\circ$C for 48 hours. In the Cr/PI system, the interface remained sharp after annealing at 325$\sp\circ$C irrespective of the ambient atmosphere. Tensile cracks formed due to residual thermal stresses. There was no significant diffusion of Cr or Cu into PI on annealing at 325$\sp\circ$C for 48 hours. Made available in DSpace on 2011-05-07T13:20:31Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9210950.pdf: 7303176 bytes, checksum: cd79cf318eb09a4f62e1962df34934cd (MD5) Previous issue date: 1991 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:53:30Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:24:45-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9210950 (UMI)AAI9210950 http://hdl.handle.net/2142/21833 eng Copyright 1991 Peddada, Satyanarayana Rao Engineering, Metallurgy Engineering, Materials Science Preparation and characterization of metal/sapphire and metal/polyimide thin film laminates text Materials Science and Engineering Materials Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.