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This thesis describes the study of a variety of nanoscale materials and the development of novel synthetic strategies for their production. While the focus and bulk of this study have been directed specifically at subwavelength lithography, a significant portion of this thesis research involves nanoparticle synthesis, characterization, and functionalization. Put in very simple terms, optical lithography is a process where a beam of light, focused in a specific pattern, is used to generate a physical pattern on a solid substrate. This technology forms the basis for almost all microchip production in the world at the present time. As demand for faster and more powerful chips increases, the need to further miniaturize the patterns while minimizing cost has become very important. Multiple photochemical systems were developed in the search for non-reciprocal photochemistry at 193 nm to increase the resolution of lithographic processes at that wavelength. One approach, based on anthracene sensitization of sulfonium salts for acid generation, used photochemically reversible 4+4 aromatic cycloaddition reactions to introduce the non-linear photochemistry. A second approach took advantage of the photochemistry of N-methylphenothiazine and provided the first true example of a lithographically-relevant multi-photon acid generating process. Since all of the systems we studied used sulfonium salts as the acid generating species, we also looked at the photochemistry of the salts themselves. We evaluated the structural effects of the salts on their direct photochemistry and the implications for sensitized multi-photon photochemistry. We found that the identity of the anion plays a significant role in both processes and propose a new photochemical mechanism for acid generation that involves a charge transfer excitation process. We also describe the synthesis and characterization of novel fluorescent silver nanoparticles, both in solution and polymer films. We show that the fluorescent images can be patterned easily and preliminary results show that photolithography based on nanoparticle formation may be possible. This latter approach could provide a facile route to nanoparticle-embedded functional materials. This work with nanoparticles was inspired partly by earlier work, also presented herein, on semiconductor nanoparticles and their interactions with disulfide ligands.

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Thesis (M.S.)--Rochester Institute of Technology, 1981. / Typescript. Includes bibliographical references (leaves 162-163).

This thesis describes the study of a variety of nanoscale materials and the development of novel synthetic strategies for their production. While the focus and bulk of this study have been directed specifically at subwavelength lithography, a significant portion of this thesis research involves nanoparticle synthesis, characterization, and functionalization. Put in very simple terms, optical lithography is a process where a beam of light, focused in a specific pattern, is used to generate a physical pattern on a solid substrate. This technology forms the basis for almost all microchip production in the world at the present time. As demand for faster and more powerful chips increases, the need to further miniaturize the patterns while minimizing cost has become very important. Multiple photochemical systems were developed in the search for non-reciprocal photochemistry at 193 nm to increase the resolution of lithographic processes at that wavelength. One approach, based on anthracene sensitization of sulfonium salts for acid generation, used photochemically reversible 4+4 aromatic cycloaddition reactions to introduce the non-linear photochemistry. A second approach took advantage of the photochemistry of N-methylphenothiazine and provided the first true example of a lithographically-relevant multi-photon acid generating process. Since all of the systems we studied used sulfonium salts as the acid generating species, we also looked at the photochemistry of the salts themselves. We evaluated the structural effects of the salts on their direct photochemistry and the implications for sensitized multi-photon photochemistry. We found that the identity of the anion plays a significant role in both processes and propose a new photochemical mechanism for acid generation that involves a charge transfer excitation process. We also describe the synthesis and characterization of novel fluorescent silver nanoparticles, both in solution and polymer films. We show that the fluorescent images can be patterned easily and preliminary results show that photolithography based on nanoparticle formation may be possible. This latter approach could provide a facile route to nanoparticle-embedded functional materials. This work with nanoparticles was inspired partly by earlier work, also presented herein, on semiconductor nanoparticles and their interactions with disulfide ligands.

Lithography is a print medium which allows the artist almost complete freedom in terms of image development. It is the fastest growing art medium on the North American Continent. However, until now, this important print medium has virtually been ignored in the high schools. The reasons for the omission in the high school art programs are financial and technical. The traditional methods of establishing a lithography workshop requires a vast amount of money, usually much more than the average art department's budget could afford. The technical difficulties involved not only in setting up the workshop but also in the processing and printing of the lithographs seemed to have finished any furthur discussion of establishing facilities at the high school level. Drawing upon fourteen years acquaintance with lithography, the experience of setting up a lithographic workshop on a small budget and experience as a high school art teacher I am attempting in this thesis to provide alternate methods for establishing a lithographic program in the schools. The teacher, although he may be lacking in any technical knowledge of lithography, should be able to follow the instructions set down in the thesis and be able to start a litho program with his classes. Included in the thesis are instruction whereby the teacher can start his classes using almost soley the existing facilities found in most art rooms or he can, if budget allows, develope a full facility including all aspects of lithography. All the equipment has been built by the writer and all the procedures have been tested. I am sure that by diligently following the instructions any art teacher could provide an interesting and rewarding lithographic program for his students. / Education, Faculty of / Graduate

Indiana University-Purdue University Indianapolis (IUPUI) / Infrared (IR) polarizers have been widely used in military and commercial applications. Controlling the polarization of incident light is one of major issues in the detector systems. However, conventional polarimetric IR detectors require series of polarizers and optical components, which increase the volume and weight of the system. In this research, stacked 1-dimensional (1-D) subwavelength grating structures were studied to develop compact size IR polarimetric detector by using surface plasmonic polariton. Experimental parameters were optimized by Finite Difference Time Domain (FDTD) simulation. Effects of gold (Au) grating size, numbers of stacked gratings, and dielectric space height were tested in the FDTD study. The fabrication of grating layers was conducted by using nanoimprint lithography. The samples were characterized by scanning electron microscopy. IR transmissions in transverse magnetic (TM) and transverse electric (TE) modes were measured by Fourier transform infrared spectroscopy (FTIR).

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Focused ion beam/scanning electron microscopy (FIB/SEM) is a tool commonly used for applications including preparation of site-specific transmission electron microscopy (TEM) samples, nanotomography, and electronic circuit edit. Another potential application is optical device prototyping; however, the ion beam itself has been shown to cause damage fatal to device operation. This thesis first includes several examples of FIB-fabricated optical devices that had limited functionality compared to simulation. Second, the underlying causes of ion beam-induced optical damage from gallium and xenon ion sources is characterized. Monte Carlo simulations of ion-solid interactions were confirmed using TEM analysis to measure the thickness of the damaged layer. For crystalline samples such as silicon, Raman response can be used as a measure of lattice damage. Using these techniques, it was found that optical damage from a gallium beam is more severe than from a xenon beam, and occurs in the form of lattice amorphization and implantation of beam ions. This damage hinders optical coupling by altering the physical and electronic structure of the sample. Consequently, the xenon PFIB is a better choice for optical device prototyping. / Thesis / Master of Science (MSc) / The second half of the 20th century saw the advent of nanotechnology, both in the context of understanding the structure of the natural world beyond the limit of light microscopy, as well as manipulating materials to create useful microscopic devices, including the computers ubiquitous in today’s life. One technology that has contributed to today’s nano-centric paradigm is the focused ion beam/scanning electron microscope (FIB/SEM). The FIB/SEM is used to machine materials with extreme precision for many diverse applications such as modifying microcircuits, three-dimensional (3D) nanotomography, or to prepare samples for other microscopy techniques. For some applications, however, damage to the sample from the ion beam can be fatal. New ion sources have become available in the past ten years that may cause less damage to samples, and thus open up new applications for FIB. This thesis includes first a description of a series of optical devices prototyped using FIB. This is followed by a comparison of the damage induced by the conventional liquid gallium ion source and new xenon plasma ion sources, and a discussion of the relative merits of the ion sources for optical device fabrication.