The fabrication characteristic of focused ion beam (FIB) for Pyrex glass was investigated. FIB has several advantages such as high sensitivity, high material removal rates, low forward scattering, and direct fabrication in selective area without any etching mask, etc. In this study, FIB etched Pyrex glass was used for fast fabrication of 3-D submicron structures. A high-aspect-ratio (HRA) glass structure of 5 (1.97µm depth/0.39µm width) was fabricated. The experimental results in terms of limiting beam size, ion dose¡]ion/cm2¡^, beam current, etc was discussed. Xenon difluoride (XeF2) was applied to enhance the FIB process. Its influence on glass fabrication is studied and characterized.

Focused Ion Beam (FIB) has several advantages such as high sensitivity, high material removal rates, low forward scattering and directing fabrication. Without any etched mask, processing time can be reduced. Pyrex glass etched by FIB is used for fast fabrication of 3-D submicron structure mold. In this study, glass is used as substrate. The UV-cured resin that spin-coated onto a mold has 3-D structure patterns. 3-D structure patterns are transferred on the plate to investigate the effects of parameters of UV cured, pressure and exposure time on the occurrence of defects. The relationship of these processing parameters for the imprinting process is also realized. Besides, the material property of UV-cured resin is investigated. UV-Cured resin is investigated by thermogravimetric Analysis (TGA) to measure the degradation temperature (Td). The hardness and modulus of UV-Cured resin was measured by nanoindentation to realize deformed ability of material for the imprinting process. Moreover, the contact angle of Pyrex glass is measured to investigate its surface quality for the imprint process.

Osseointegration, or the direct integration of an implant into bone tissue, is necessary for implant success. Titanium is commonly used clinically in dental and orthopaedic implants because of its passivating oxide layer, which facilitates osseointegration, and its mechanical properties such as a modulus of elasticity similar to bone. Diverse studies have shown that surface microtopography, chemistry, and surface energy affect osteoblast behavior. The problem with these studies is that they access the average behavior of a culture in response to a substrate and not the behavior of individual cells. The objective of this study was to develop a method for correlating the behavior of individual cells with the characteristics of the surface underneath them. More specifically, this work developed a method to correlate integrin beta-1 (β1) expression with the surface characteristics under individual cells. Integrins are cell surface receptors that bind to specific proteins in the extracellular matrix adsorbed on the implant surface. Previous work has shown that expression of certain integrins is increased when osteoblasts on titanium substrates develop a more differentiated phenotype, and that integrin β1 is necessary for osteoblast response to roughness on titanium substrates. This study used molecular beacons specific to integrin β1 to quantify integrin β1 expression of MG63 cells cultured on titanium disks. A template was designed to coordinate the location of cells using fluorescence microscopy and scanning electron microscopy (SEM) in reference to laser etchings on the disks. After live cell imaging, cells were fixed, dried, and critical point dried for focused ion beam (FIB) milling. Transmission electron microscopy (TEM) sections of cells identified with high and low integrin β1 molecular beacon intensity were milled, and cells with high and low integrin β1 molecular beacon intensity were also serial sectioned. While our TEM results were inconclusive, SEM images from serial sectioning showed contact points between the cell body and the substrate, consistent with previous results. Cells cultured on pretreatment (PT) or sandblasted acid etched (SLA) titanium surfaces were also serial sectioned, showing that cells on SLA surfaces have more regions of contact between the cells and the substrate than cells on PT surfaces. This work is significant as it is the first study to develop a method to correlate individual cell behavior with the substrate surface characteristics under the individual cells. Previous studies have reported the average cell behavior in response to their substrates, while this work allows for the study of substrate surface characteristics that positively affect integrin β1 expression in individual cells. Further optimization of the fluorescence imaging process and FIB milling process could be done, and the method developed in this study could be used in future studies to investigate surface characteristics after using other fluorescent analyses of cell behavior, such as immunocytochemistry.

The rapid growth of the microelectronics industry in the last decades made it possible to produce structures in the sub-micrometer scale on silicon chips and to reach an integration scale under 100 nm. Decreasing the size and increasing the complexity of these structures make a control of quality and defects investigation more difficult. During a long time ultrasound devices are being used for nondestructive investigation of materials, like ultrasound microscopes, scanning photo-acoustic microscopes or scanning electron-acoustic microscopes, where acoustic waves are generated by acoustic transducers, focused laser or electron beams, respectively. The aim of this work is to investigate more precisely the acoustic wave generation by pulsed and periodically modulated ion beams in different solid materials depending on the beam parameters and to demonstrate the possibility to apply an intensity modulated focused ion beam (FIB) for acoustic emission and for nondestructive investigation of the internal structure of materials on a microscopic scale. The combination of a FIB and an ultrasound microscope in one device can provide the opportunity of nondestructive investigation, production and modification of micro- and nanostructures simultaneously. The FIB spot size in modern systems is comparable with that of a focused electron beam and the penetration depth of ions with energy of 20-60 keV is lower than 100 nm. This makes it possible to reach a sub-micrometer resolution of a scanning ion acoustic microscope. On the other hand side a FIB with energy of 20-60 keV is a good tool which can be used for the fabrication of nanostructures using ion milling, implantation or ion beam assisted deposition techniques. The bulk ultrasound emission in a solid was investigated using a pulsed high energy ion beam focused on aluminum, copper, iron and silicon samples. Oxygen, silicon and gold ion beams were applied in charge states from 1+ to 4+ with the pulse duration of 0.5 - 4 µs and an energy of 1.5 - 10 MeV. Intensity of the detected acoustic waves shows a linear dependence on the energy of the incident ions, on the ion flux as well as on the pulse duration. No influence of the ion charge and ion mass to the emission of acoustic waves was observed. The ion acoustic effect was applied for a nondestructive material inspection using intensity modulated FIB providing by the IMSA-100 FIB system with an accelerating potential of 30-35 kV. The achieved lateral resolution of this scanning ion acoustic microscope is in the micrometer range depending on the sample material and the beam modulation frequency. The resolution can be improved by increasing the frequency. The maximal modulation frequency which was obtained at IMSA-100 is about 2 MHz corresponding to lateral resolution of 4-5 µm on silicon. Using this microscope, some images of integrated microstructures on a silicon chip were obtained using the lock-in technique for filtering of the signal from the noise and increasing of the total imaging time. The possibility to visualize near sub-surface structure was demonstrated. Due to the strong sputtering effect and the long time of irradiation the imaged structures were significantly damaged. Si2+, Ge2+, Ga+ and Au+ ions were used. All these ions are quite heavy and have high sputtering coefficients. Long-time imaging improves the quality of acoustic images, i. e. the signal-to-noise ratio is reduced with the square root from the pixel time, but leads to significant erosion of the imaged structure.

Titanium carbide (TiC) and titanium carbonitride (Ti(C,N)) are both common components in hard, wear resistant ceramic-metal composites, or cermets. In this study the intermetallic nickel aluminide (Ni3Al) has been used as a binder for the production of TiC and Ti(C,N) based cermets. These cermets offer several improved characteristics relative to conventional WC-based ‘hardmetals’, such as lower mass and improved oxidation resistance, which are also combined with high fracture resistance, hardness and wear resistance. The cermets were produced using an in-situ, reaction sintering procedure to form the stoichiometric Ni3Al binder, with the binder contents varied from 20 to 40 vol%. However, for high N content Ti(C,N) cermets, the wettability of molten Ni3Al is relatively poor, which leads to materials with residual porosity. Therefore various amounts of Mo2C (1.25, 2.5, 5 and 10 vol%) were incorporated into the Ti(C0.3,N0.7)-Ni3Al cermets, with the aim of improving the densification behaviour. Mo2C was found to improve upon the wettability during sintering, thus enhancing the densification, especially at the lower binder contents. The tribological behaviour of TiC and Ti(C,N) cermets have been evaluated under reciprocating sliding conditions. The wear tests were conducted using a ball-on-flat sliding geometry, with a WC-Co sphere as the counter-face material, for loads from 20 to 60 N. The wear response was characterised using a combination of scanning electron microscopy, energy dispersive X-ray spectroscopy, and focused ion beam microscopy. Initially, two-body abrasive wear was observed to occur, which transitions to three-body abrasion through the generation of debris from the cermet and counter-face materials. Ultimately, this wear debris is incorporated into a thin tribolayer within the wear track, which indicates a further transition to an adhesive wear mechanism. It was found that Mo2C additions had a positive effect on both the hardness and indentation fracture resistance of the samples, but had a detrimental effect on the sliding wear response of the cermets. This behaviour was attributed to increased microstructural inhomogeneity with Mo2C additions.

This thesis presents a method for dynamic characterization of MEMS structures and discuses parameters that affect its measurements and techniques to improve them. Current methods of non-contact, laser based vibration measurement require special and expensive instruments. The method used in this thesis on the other hand, relies on Fast Fourier Transform analysis of blurred images captured using conventional cameras. The Fourier series analysis and transformation are introduced. Basic concepts of blur image analysis and associated technical terms are described. Step by step data extraction process for Fourier analysis of blurred images and results such as amplitude, attenuation, signal to noise ratio and Bessel curve are explained. Macro and micro scale experiments are designed and used to determine the effect and significance of different parameters on signal-to-noise ratio of extracted results. For this purpose geometrical parameters of macro scale combs such as length, width and duty cycle are varied across a considerable range and tests results are examined. In addition to the experiments, MATLAB code is used to model environmental effects such as addition of noise or changes of brightness. In micro scale experiments, extra patterns are created using Focused Ion Beam and etching process. Test and comparison of modified micro structures with unpatterned structures show improvement in signal to noise ratio especially in environments with high level of noise.

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The procedure for milling micrometre scale cantilevers of lutetium iron garnet using a focused ion beam microscope was developed. The infrastructure to study these cantilevers using rotational hysteresis loops and ferromagnetic resonance experiments was set up. The cantilevers were shown to remain magnetic after milling, and the origin of their hysteresis loops investigated with a variant of the Stoner-Wohlfarth model. Ferromagnetic resonance in the cantilevers was demonstrated as the first step towards studying magnetomechanical coupling.

The ability to generate three dimensional (3D) microstructures in solids is of great importance in understanding their true nature, as it eliminates speculation about the spatial distribution of features associated with conventional two dimensional (2D) imaging techniques. There are several recently-developed 3D techniques for determining the spatial distribution of microstructural features, each with a given resolution. There is considerable interest in the development of a specific serial sectioning methodology, termed 3D electron backscatter diffraction (3D-EBSD), which combines a focused ion beam (FIB) with EBSD interfaced to a field emission gun scanning electron microscope. Here, FIB is used as a serial sectioning device for cutting parallel slices of single- and multi-phase materials with a site-specific accuracy of up to 50 nm. Each consecutive slice is mapped by EBSD and the complete dataset combined using advanced computer algorithms to generate a volume of a material whereby the true crystallographic features can be analyzed at submicron resolution. The aims of the thesis was to develop 3D-EBSD into a powerful materials analysis tool and use it to resolve several issues concerning the nature of the deformed state and the nucleation and the growth behaviour of recrystallizing grains. The study commenced with an investigation into the effect of material type (restricted to face centred cubic AI, Cu and Au metallic crystals), FIB milling conditions and EBSD software variables on the quality of EBSD patterns generated on ion-milled surfaces of these materials. The effect of material type on EBSD pattern quality following FIB milling was found to be significant with relatively poor quality EBSD patterns obtained for metals of low atomic number. It was demonstrated, particularly for the high atomic number metals, that moderate FIB milling currents (~1-5nA) generated good quality EBSD maps from a given ion-milled surface. This preliminary work was necessary for balancing the time required for serial sectioning during 3D-EBSD and the generation of sufficient quality EBSD maps from each ion-milled surface. The outcomes of this investigation were applied to two major 3D-EBSD investigations on the microstructural and crystallographic characteristics of: (i) deformation features generated in a cold rolled interstitial free (IF) steel, with particular emphasis on the formation of microbands; and (ii) recrystallization of a cold rolled nickel alloy containing coarse (>1 ??m) silica particles, with particular attention given to the generation of particle deformation zones and their influence on nucleation and growth of recrystallizing grains including particle stimulated nucleation (PSN), twin formation during PSN and the growth behaviour of various types of grain boundary into the deformation microstructure. The foregoing 3D-EBSD studies were significant as they revealed various microstructural and crystallographic features not usually clearly evident in conventional 2D micrographs obtained by either EBSD or optical metallography. For example, the technique demonstrated that microbands in cold rolled IF steel consist of irregular curved surfaces that reconcile findings that microbands straight and aligned parallel to slip planes when viewed in normal direction-rolling direction sections but are wavy in transverse direction-rolling direction sections. Three slip planes were found within the angular range of the curved surface of the microband, which indicates that multiple slip planes are operative during deformation. The work also showed the influence of particle diameter on the misorientations generated within particle deformation zones and clearly showed that particle stimulated nucleation (PSN) occurred at particles greater than 1.5-2 ??m. It was observed that PSN in the nickel sample also generates contiguous grains separated by both coherent and incoherent twin boundaries and, on further growth of these grains into the matrix, the coherent boundary dominates and remains parallel to the primary growth direction of the grains.