Thesis (M.S.) in Electrical Engineering--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 92-96).

Thesis (M. Eng.)--Carleton University, 1988. / Also available in electronic format on the Internet.

Thesis (Ph. D.)--Boise State University, 2009. / Includes abstract. Includes bibliographical references (leaves 104-112).

Thesis (Ph. D.)--Boise State University, 2009. / Title from t.p. of PDF file (viewed Apr. 26, 2010). Includes abstract. Includes bibliographical references (leaves 104-112).

No description available.

No description available.

One class of Surface Acoustic Wave (SAW) devices employs reflecting arrays to determine device characteristics. Dots of metal film and grooves have been used as reflectors; reflection is caused by the mechanical discontinuity. This research project is a study of an alternative reflector, the thin metal dot, which reflects by interacting with the electric field that accompanies the SAW on a piezo-electric material. Experimental work is done on Y-cut LiNbO₃, a common SAW material, the aim being to characterise the reflection mechanism sufficiently to design devices, particularly on this material. Reflectivities of a large range of dot sizes is reported. Velocity change due to dots, another parameter required in device design, is also measured. In addition, holes in a metal film, physically the opposite of dots, are also studied. A theorectical model is developed to predict the behaviour of dots in devices. For a <strong>Z</strong>-propagating wave in LiNbO₃, the SAW velocity for completely free and completely metallised surfaces were used to specify the properties of the material. For propagation in other directions on the surface, particularly near the <strong>X</strong> direction, a different acoustic mode, the Leaky Surface Wave (LSW), has an influence on SAW reflections, and the model also requires the LSW velocities under the same two conditions. The model uses these parameters, together with dot geometry, to determine reflectivity in any direction and velocity change due to the dots. The results agree well with experiments. A device (a RAC) is designed using this model, to bring out any unforseen difficulties in the use of dot arrays. The device performed as expected except for some unanticipated attenuation in the arrays, which can almost certainly be predictably allowed for in future designs, being broadband and not very severe.

We determine the crustal and upper mantle structure within the northern Canadian Cordillera using two complementary Rayleigh wave analysis techniques: ambient noise and teleseismic two-station interferometry. These methods are used to measure Rayleigh waves propagating between all available pairs of seismic stations in northwestern Canada, which are processed to obtain phase velocity dispersion curves. These curves provide information on the inter-station, path-averaged phase velocity as a function of frequency (or period). These inter-station phase velocities are then inverted to produce phase velocity maps. Phase velocity maps for periods between 8 and 80 s show to first-order high velocities within the Shield and low velocities within the Cordillera, supporting the thermal isostasy model for the region. Smaller scale features are observed throughout the Cordillera with high velocities west of the Tintina Fault reflecting the mafic composition of the accreted terranes of the Intermontane belt, and low velocities east of the Tintina fault reflecting the sedimentary rocks of the Selwyn Basin. High velocities extending west past the Cordilleran Deformation Front provide evidence for the existence of regions within the eastern Cordillera underlain by cool cratonic lithosphere. Anisotropy within the upper crust and mantle shows fast-axis orientations in line with the major faults within the region, providing evidence for a shear-zone that extends to lithospheric mantle depths. Lower crustal anisotropy shows an increase in heterogeneity of fast-axis orientations, which provides limited support for the existence of a weak shear zone and detachment within the lower crust. Results of a 1D inversion show approximate Moho depths of 35 km for the region west of the Tintina Fault, 36 km for the Mackenzie Mountains region, and 37 km for the shield. Reduced lower crust velocities observed throughout the Cordillera, provide support for the existence of a weak lower crustal layer.

Surface Acoustic Wave (SAW) devices are manufactured using standard metallization and photolithographic techniques that have been established by the semiconductor industry. The facilities in the newly developed Microelectronics laboratory at the University of Central Florida will be utilized in the fabrication of a SAW device. This thesis will outline the complete procedure beginning with the initial design from given specifications, up to mask generation, fabricating and testing of the device. This will serve to calibrate the fabrication process for future work in SAW device and semiconductor fabrication. The models that are used in the SAWCAD design software will be verified by comparing the theoretical and experimental results.

Typescript (photocopy). / Digitized by Kansas Correctional Industries