Large area high throughput metrology plays an important role in several technologies like MEMS. In current metrology systems the parallel operation of multiple metrology probes in a tool has been hindered by their bulky sizes. This study approaches this problem by developing a metrology technique based on miniaturized scanning grating interferometers (μSGIs). Miniaturization of the interferometer is realized by novel micromachined tunable gratings fabricated using SOI substrates. These stress free flat gratings show sufficient motion (~500nm), bandwidth (~50 kHz) and low damping ratio (~0.05). Optical setups have been developed for testing the performance of μSGIs and preliminary results show 6.6 μm lateral resolution and sub-angstrom vertical resolution. To achieve high resolution and to reduce the effect of ambient vibrations, the study has developed a novel control algorithm, implemented on FPGA. It has shown significant reduction of vibration noise in 6.5 kHz bandwidth achieving 6x10-5 nmrms/√Hz noise resolution. Modifications of this control scheme enable long range displacement measurements, parallel operation and scanning samples for their dynamic profile. To analyze and simulate similar optical metrology system with active micro-components, separate tools are developed for mechanical, control and optical sub-systems. The results of these programs enable better design optimization for different applications.

A comprehensive study of a miniaturized thermally activated cooling system was conducted. This study represents the first work to conceptualize, design, fabricate and successfully test a thermally activated cooling system for mobile applications. Thermally activated systems have the ability to produce useful cooling from waste heat streams or directly from the combustion of liquid fuels. Numerous concepts of miniaturized or mobile, active cooling systems exist in the literature but up to this point, successful fabrication and testing has not been documented. During this study, a breadboard absorption heat pump system was fabricated from off the shelf or in-house, custom-built components. The breadboard system was used to validate the feasibility of operating an absorption heat pump with a cooling capacity of about 300 W. Subsequently, a flexible and scalable design methodology for designing miniaturized absorption heat pumps was developed. A miniaturized, 300 W nominal cooling capacity ammonia/water absorption heat pump cycle with overall dimensions of 200 × 200 × 34 mm and a mass of 7 kg was then fabricated and tested. Testing of the absorption heat pump was conducted over a range of heat sink temperatures (20 ≤ T ≤ 35°C) and desorber thermal input rates (500 ≤ Q ≤ 800 W). Evaporator coolant heat duties in the study ranged from 136 to 300 W, while system COPs ranged from 0.247 to 0.434. At a nominal rating condition of 35°C heat sink temperature, the maximum thermal input of 800 W produced a cooling effect of 230 W. This represents a cycle COP of 0.29. Analysis of the experimental data indicated that future work should focus on improved desorber and rectifier designs to improve refrigerant purity. It is estimated that a system similar to the one in this study, with all fluid connections made internal to the system, could achieve the same cooling capacity with a system mass of 2.5 - 3.5 kg in an envelop of 120 × 120 × 25 mm.

Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Mechanical Engineering, 2008. / Includes bibliographical references.

Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Danyluk, Steven; Committee Member: Butler, David; Committee Member: Hesketh, Peter; Committee Member: Yoda, Minami. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Ghiaasiaan, S. Mostafa; Committee Member: Desai, Prateen; Committee Member: Jeter, Sheldon; Committee Member: Kirkconnell, Carl.

Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Mechanical Engineering, 2009. / Includes bibliographical references.

Optical biosensors are increasingly being considered for lab-on-a-chip applications due to their benefits such as small size, biocompatibility, passive behaviour and lack of the need for fluorescent labels. The light guiding mechanisms used by many of them result in poor overlap of the optical field with the target molecules, reducing the maximum sensitivity achievable. This thesis presents a new platform for optical biosensors, namely slotted photonic crystals, which engender higher sensitivities due to their ability to confine, spatially and temporally, the peak of optical mode within the analyte itself. Loss measurements showed values comparable to standard photonic crystals, confirming their ability to be used in real devices. A novel resonant coupler was designed, simulated, and experimentally tested, and was found to perform better than other solutions within the literature. Combining with cavities, microfluidics and biological functionalization allowed proof-of-principle demonstrations of protein binding to be carried out. High sensitivities were observed in smaller structures than most competing devices in the literature. Initial tests with cellular material for real applications was also performed, and shown to be of promise. In addition, groundwork to make an integrated device that includes the spectrometer function was also carried out showing that slotted photonic crystals themselves can be used for on-chip wavelength specific filtering and spectroscopy, whilst gas-free microvalves for automation were also developed. This body of work presents slotted photonic crystals as a realistic platform for complete on-chip biosensing; addressing key design, performance and application issues, whilst also opening up exciting new ideas for future study.

Two types of rotary gate microvalves are developed for flow modulation in a microfluidic system that operates at high flow rate and/or uses particulate flow. This research work encompasses design, microfabrication, and experimental evaluation of these microvalves in three distinct areas compliant micromechanism, microfluidics, and electromagnetic actuation. The microvalve consists of a suspended gate that rotates in the plane of the chip to regulate flow through the orifices. The gate is suspended by a novel fully-compliant in-plane rotary bistable micromechanism (IPRBM) that advantageously constraints the gate in all other degrees of freedom. Multiple inlet/outlet orifices provide flexibility of operating the microvalve in three different flow/port configurations. The suspended gate is made of a soft magnetic material and is electromagnetically actuated like a rotor in a variable-reluctance stepper motor. Therefore, an external electromagnetic (EM) actuation at the integrated set of posts (stator) causes the gate mass to switch from its default angular position to a second angular position. The microvalve chip is fabricated by electroplating a soft magnetic material, Permalloy (Ni80Fe20) in a sacrificial photoresist mold on a Silicon substrate. The inlet/outlet orifices are then etched into the Silicon substrate from the back-side using deep-reactive ion etch process. Finally, the gate structure is released by stripping the PR and seed layers. This research work presents the realization of a new microvalve design that is distinct from traditional diaphragm-type microvalves. The test results are encouraging and show the potential of these microvalves in effectively modulating flow in microfluidic systems that may not require a tight seal. The microvalve uses a novel in-plane rotary bistable micromechanism that may have other applications such as optical shutters, micro-locks, and passive check valves.

Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Systems Science and Industrial Engineering, 2008. / Includes bibliographical references.