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As the gate density increases in microelectronic devices, the interconnect delay or RC response also increases and has become the limiting delay to faster devices. In order to decrease the RC time delay, a new metallization scheme has been chosen by the semiconductor industry. Copper has replaced aluminum as the metal lines and new low-k dielectric materials are being developed to replace silicon dioxide. A promising low-k material is porous organosilicate glass or p-OSG. The p-OSG film is a hybrid material where the silicon dioxide backbone is terminated with methyl or hydrogen, reducing the dielectric constant and creating mechanically weak films that are prone to fracture. A few methods of improving the mechanical properties of p-OSG films have been attempted-- exposing the film to hydrogen plasma, electron beam curing, and ultra-violet light curing. Hydrogen plasma and electron-beam curing suffer from a lack of specificity and can cause charging damage to the gates. Therefore, ultra-violet light curing (UV curing) is preferable. The effect of UV curing on an ultra-low-k, k~2.5, p-OSG film is studied in this dissertation. Changes in the molecular structure were measured with Fourier Transform Infrared Spectroscopy and X-ray Photoelectron Spectroscopy. The evolution of the molecular structure with UV curing was correlated with material and fracture properties. The material properties were film shrinkage, densification, and an increase in dielectric constant. From the changes in molecular structure and material properties, a set of condensation reactions with UV light are predicted. The connectivity of the film increases with the condensation reactions and, therefore, the fracture toughness should also increase. The effect of UV curing on the critical and sub-critical fracture toughness was also studied. The critical fracture toughness was measured at four different mode-mixes-- zero, 15°, 32°, and 42°. It was found that the critical fracture toughness increases with UV exposure for all mode mixes. The sub-critical fracture toughness was measured in Mode I and found to be insensitive to UV cure. A simple reaction rate model is used to explain the difference in critical and sub-critical fracture toughness. / text

A study was made of the thermoreflectance spectra of a series of five thin film samples spanning the range of composition of the amorphous Ge(x)Te(1-x) binary semiconductors. The experiment was performed over photon energies ranging from 0.5 ev in the infrared to 6 ev in the ultraviolet. The results are plotted for energies above the absorption edge. In the Ge-rich materials there was little structure in the thermoreflectance spectrum. However, there was the development of two peaks in the spectrum as the Te content was increased beyond a 50:50 mixture. The results are analyzed in terms of optical constants and electronic structure. It was found that the energy separation of the peaks in the thermoreflectance corresponded closely to the separation of peaks in the valence band density of states seen in photoemission experiments. The existence of the two peaks indicates a "lone pair" band of energy levels positioned between the valence and conduction bands. This is aditional evidence of two-fold coordination of the Te atoms in these materials. At energies below the band gap there was strong interference due to increased transimission of the film. This made the analysis more complicated. A procedure is discussed for extracting from the modulated interference the specific changes occurring in the optical constants with temperature modulation.

No description available.

Thesis (M.S.)--Ohio University, March, 2000. / Title from PDF t.p.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.

Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Robert L. Opila, Dept. of Materials Science & Engineering. Includes bibliographical references.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references (leaves 76-77). Also available in electronic version. Access restricted to campus users.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references. Also available in electronic version. Access restricted to campus users.

Thesis (M. Eng.)--Carleton University, 1992. / Also available in electronic format on the Internet.