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Rapid Prototyping Of Microfluidic PackagesPepper, Michael 01 January 2006 (has links)
In the area of MEMS there exists a tremendous need for communication between the micro-device and the macro world. A standard protocol or at least multiple standards would be of great use. Electrical connections have been standardized for many uses and configurations by the integrated circuit industry. Standardization in the IC industry has created a marketplace for digital devices unprecedented. In addition to the number of "off the shelf" products available, there exists the possibility for consumers to mix and match many devices from many different manufacturers. This research proposes some similar solutions as those for integrated circuits for fluid connections and mechanical configurations that could be used on many different devices. In conjunction with offering the capability to facilitate communication between the micro and macro worlds, the packaging solutions should be easy to fabricate. Many devices are by nature non-standard, unique, designs that make a general solution difficult. At the same time, the micro-devices themselves will inevitably need to evolve some standardization. In BioMEMS devices the packaging issue is concerned with delivering a sample to the device, conducting the sample to the sensor or sensors, and removing the sample. Conducting the sample to the sensor or sensors is usually done with microchannels created by standard MEMS fabrication techniques. Many current designs then utilize conventional machining techniques to create the inlet and outlet for the sample. This work proposes a rapid prototyping method for creating the microchannel and inlet / outlet in simplified steps. The packages developed from this process proved to be an effective solution for many applications.
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The Creation of an Anodic Bonding Device Setup and Characterization of the Bond Interface Through the Use of the Plaza TestMcCrone, Tim M 01 March 2012 (has links) (PDF)
Recently there has been an increased focus on the use of microfluidics for the synthesis of different products. One of the products proposed for synthesis is quantum dots. Microfluidics often uses Polydimethylsiloxane for structure in microfluidic chips, but quantum dots use octadecene in several synthesis steps. The purpose of this work was to create a lab setup capable of anodically bonding 4” diameter wafers, and to characterize the bond formed using the Plaza test chip so that microfluidic devices using glass and silicon as substrates could be created.
Two stainless steel electrodes placed on top of a hot plate were attached to a high power voltage supply to perform anodic bonding. A Plaza test mask was created and used to pattern P type silicon wafers. The channels etched were between 300 and 500nm deep and ranged between 1000µm and 50µm. These wafers were then anodically bonded to Corning 7740 glass wafers. Bonding stopped once the entire surface of the wafer was bonded, determined by visual inspection. All bonds were formed at 400°C and the bond strength and toughness between wafers bonded at 400V and 700V was compared.
A beam model was used to predict the interfacial fracture toughness, and the stress at the bond was calculated with a parallel spring model. By measuring the crack length of the test structures under a light microscope the load conditions of the beam could be found. It was concluded that the electrostatic forces between the wafers give the best indication of what the bond quality will be. This was seen by the large difference in crack length between samples that were bonded using a thick glass wafer (1 mm) and a thin glass wafer (500µm). The observed crack lengths for the thick glass wafers were between 40 and 60µm. Thin glass wafers had a crack length between 20 and 40µm. The fracture toughness was calculated using the beam model approximation. Fracture toughness of the thin glass wafers was 7MPa m1/2, and of the thick glass wafers was 30 MPa m1/2. The fracture toughness of the thick glass wafers agreed with results found through the use of the double cantilever beam samples in literature. The maximum observed interfacial stress was 70 MPa.
Finally, to measure the change in the size of the sodium depletion zone formed during bonding, samples were placed under a scanning electron microscope (SEM). Depletion zones were found to be between 1.1 and 1.4µm for thin glass samples that were bonded at 400 and 700 volts. This difference was not found to have a significant effect on the strength or fracture toughness observed. Thicker glass samples could not have their depletion zone measured due to SEM chuck size.
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Nonlinear Dynamics of Annular and Circular Plates Under Thermal and Electrical LoadingsFaris, Waleed Fekry 27 January 2004 (has links)
The nonlinear static and dynamic response of circular and annular plates under electrostatic, thermal, and combined loading is investigated. The main motivation for the study of these phenomena is providing fundamental insights into the mechanics of micro-electro-mechanical-systems (MEMS). MEMS devices are usually miniaturization of the corresponding macro-scale devices. The basic mechanics of the components of many MEMS devices can be modeled using conventional structural theories. Some of the most used and actively researched MEMS devices- namely pressure sensors and micropumps- use circular or annular diaphragms as principle components. The actuation and sensing principles of these devices are usually electrostatic in nature. Most MEMS devices are required to operate under wide environmental conditions, thus, a study of thermal effects on the performance of these devices is a major design consideration.
There exists a wide arsenal of analytic, semi-analytic, and numerical tools for nonlinear analysis of continuous systems. The present work uses different tools for the analysis of different types of problems. The selection of the analysis tools is guided by two principles. The first consideration is that the analysis should reveal the fundamental mechanics and dynamics of the problem rather than simply generating numerical data. The second consideration is numerical efficiency. Guided by the same principles, the basic structural model adopted in this work is the von-Karman plate model. This model captures the basic nonlinear phenomena in the plate with minimal complexity in the equations of motion, thus providing a balance between simplicity and accuracy.
We address a wide array of problems for a variety of loading and boundary conditions. We start by analyzing annular plates under static electrostatic loading including the variation of the plate natural frequencies with the applied voltage. We also analyze parametric resonances in plates subjected to sinusoidally varying thermal loads. We investigate the prebuckling and postbuckling static thermal response and the corresponding variation of the natural frequencies. Finally, we close by investigating the problem of a circular plate under a combination of thermal and electrostatic loading. The results of this investigation demonstrate the importance of including nonlinear phenomena in the modeling of MEMS devices both for correct quantitative predictions and for qualitative description of operations. / Ph. D.
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Kinematic State Estimation using Multiple DGPS/MEMS-IMU SensorsKu, Do Yeou 21 October 2022 (has links) (PDF)
Animals have evolved over billions of years and understanding these complex and intertwined systems have potential to advance the technology in the field of sports science, robotics and more. As such, a gait analysis using Motion Capture (MOCAP) technology is the subject of a number of research and development projects aimed at obtaining quantitative measurements. Existing MOCAP technology has limited the majority of studies to the analysis of the steady-state locomotion in a controlled (indoor) laboratory environment. MOCAP systems such as the optical, non-optical acoustic and non-optical magnetic MOCAP systems require predefined capture volume and controlled environmental conditions whilst the non-optical mechanical MOCAP system impedes the motion of the subject. Although the non-optical inertial MOCAP system allows MOCAP in an outdoor environment, it suffers from measurement noise and drift and lacks global trajectory information. The accuracy of these MOCAP systems are known to decrease during the tracking of the transient locomotion. Quantifying the manoeuvrability of animals in their natural habitat to answer the question “Why are animals so manoeuvrable?” remains a challenge. This research aims to develop an outdoor MOCAP system that will allow tracking of the steady-state as well as the transient locomotion of an animal in its natural habitat outside a controlled laboratory condition. A number of researchers have developed novel MOCAP systems with the same aim of creating an outdoor MOCAP system that is aimed at tracking the motion outside a controlled laboratory (indoor) environment with unlimited capture volume. These novel MOCAP systems are either not validated against the commercial MOCAP systems or do not have comparable sub-millimetre accuracy as the commercial MOCAP systems. The developed DGPS/MEMS-IMU multi-receiver fusion MOCAP system was assessed to have global trajectory accuracy of _0:0394m, relative limb position accuracy of _0:006497m. To conclude the research, several recommendations are made to improve the developed MOCAP system and to prepare for a field-testing with a wild animal from a family of a terrestrial megafauna.
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Recent Progress in the Design of 4G/5G Reconfigurable FiltersAl-Yasir, Yasir I.A., Ojaroudi Parchin, Naser, Abd-Alhameed, Raed, Abdulkhaleq, Ahmed M., Noras, James M. 16 January 2019 (has links)
Yes / Currently, several microwave filter designs contend for use in wireless communications.
Among various microstrip filter designs, the reconfigurable planar filter presents more advantages
and better prospects for communication applications, being compact in size, light-weight and
cost-effective. Tuneable microwave filters can reduce the number of switches between electronic
components. This paper presents a review of recent reconfigurable microwave filter designs,
specifically on current advances in tuneable filters that involve high-quality factor resonator filters to
control frequency, bandwidth and selectivity. The most important materials required for this field
are also highlighted and surveyed. In addition, the main references for several types of tuneable
microstrip filters are reported, especially related to new design technologies. Topics surveyed include
microwave and millimetre wave designs for 4G and 5G applications, which use varactors and
MEMSs technologies. / This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424.
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Microeletromechanical Systems for Tunable Ring Resonators on a Silicon PlatformNguyen, Chris Phong Van January 2021 (has links)
Advancements in photonic integrated circuits, so-called PICs, have progressed fast in the last decades. More complex PICs are getting developed, which are promising in possibly offering advantages like low power consumption and high-performance computing. Re-programmable photonic FPGAs are one of these candidates. To make these PICs viable, fundamental building blocks based on photonics need to be developed. Some of those fundamental building blocks are tunable silicon ring resonators, which can be used to filter signals in the transmission of light through photonic circuits. Fabrication of PICs is developing and those components are getting smaller, which leads to a strong sensitivity of their behavior to nanometer-scale variations. That has created a need for active tuning of those devices to recuperate those variances. One promising way to tune silicon ring resonator devices is to integrate microelectromechanical systems (MEMS) into the tuning section of the devices, because of their local and low power actuation. They are prospective to eliminate drawbacks from usual actuation methods like thermal actuation, which comes with high power consumption and cross talk while heating the functional sections of the ring. In this thesis, we have measured and analyzed MEMS-tunable silicon ring resonators, featuring two different designs, being an all-pass ring resonator and an add-drop ring resonator. The MEMS in the design are used to change the gap between the waveguides in their directional coupler and phase shifter section to control the position and extinction ratios of the ring resonance dips, which has been successfully demonstrated for the all-pass ring resonator. For the add-drop ring resonators, we have obtained performance parameters of their resonances with an average Q-factor of 3000 over the measured wavelength ranged from 1460nm to 1580nm and the characteristic behavior of their transmission has been shown without actuation. Further investigation with MEMS actuation of add-drop ring resonators and passive measurements on all-pass ring resonators can be done for a better understanding of their behavior and functionality. This can be achieved by characterizing all-pass ring resonators in terms of obtained performance parameters and by active measurements on add-drop ring resonators, as we expect that their MEMS could enable similar functionalities as all-pass ring resonators. Our first characterization results confirm the potential of MEMS for ring resonator tuning and could enable future circuits based on ring resonators with low power consumption. / Framsteg inom fotoniska integrerade kretsar, så kallade PIC, har utvecklats snabbt under de senaste decennierna. Mer komplexa PIC utvecklas, vilket lovar att möjligen erbjuda fördelar som låg strömförbrukning och högpresterande datorer. Omprogrammerbara fotoniska FPGA är en av dessa kandidater. För att göra dessa PICs livskraftiga måste grundläggande byggstenar baserade på fotonik utvecklas. Några av dessa grundläggande byggstenar är avstämningsbara kiselringresonatorer, som kan användas för att filtrera signaler vid överföring av ljus genom fotoniska kretsar. Tillverkning av PIC utvecklas och dessa komponenter blir mindre, vilket leder till en stark känslighet för variationer, även på nanometer skala. Det har skapat ett behov av aktiv inställning av dessa enheter för att återhämta dessa avvikelser. Ett lovande sätt att ställa in kiselringresonatoranordningar är att integrera mikroelektromekaniska system (MEMS) i enhetens stämningsdel på grund av deras lokala och lågeffektaktivering. De kan eliminera nackdelar med vanliga manövreringsmetoder som termisk aktivering, som kommer med hög strömförbrukning och termisk överhöring. I denna avhandling har vi mätt och analyserat MEMS-avstämbara kiselringresonatorer, med två olika designer, som är en all-pass ringres-onator och en add-drop ringresonator. MEMS i konstruktionen används för att ändra gapet mellan vågledarna i deras kopplare och fasskiftarsektion för att styra positionen och djupet på ringresonaserna, vilket har visats framgångsrikt för allpassningsresonatorn. För add-dropringresonatorer har vi erhållit prestandaparametrar för deras resonanser med en genomsnittlig Q-faktor på 3000 över den uppmätta våglängden som varierar från 1460 nm till 1580 nm och det karakteristiska beteendet för deras överföring har visats utan aktivering. Ytterligare undersökning med MEMS-aktivering av add-drop-ringresonatorer och passiva mätningar på all-pass-ringresonatorer kan göras för en bättre förståelse av deras beteende och funktionalitet. Detta kan uppnås genom att karakterisera allpassningsresonatorer i termer av erhållna prestandaparametrar och genom aktiva mätningar på add-drop-ringresonatorer, eftersom vi förväntar oss att deras MEMS kan möjliggöra liknande funktioner som all-pass-ringresonatorer. Våra första karakteriseringsresultat bekräftar MEMS potential för ringresonatorinställning och kan möjliggöra framtida kretsar baserade på ringresonatorer med låg strömförbrukning.
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Analog Temperature Control Circuit for a Thin-Film Piezoelectric-on-Substrate Microelectromechanical Systems OscillatorHofstee, Heather 01 January 2018 (has links)
The objective and motivation for this project is to design a low-power, low-noise oven-control circuit to optimize the stability of a MEMS oscillator. MEMS oscillators can be fabricated using conventional semiconductor manufacturing methods and can often be assembled in packages smaller than those of traditional crystal oscillators. However, one of their largest disadvantages currently is their high temperature coefficient of frequency (TCF), causing MEMS oscillators to be especially sensitive to temperature changes. Hence, this project focuses on designing a printed circuit board that will allow the user to manually tune a current passing through a resonator wire-bonded to the board to elevate the resonator temperature. This will ensure that the device's resonance frequency stays largely constant and that the oscillator provides a very stable signal.
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Copper Sulfide Solid-State Electrolytic Memory DevicesYou, Liang January 2007 (has links)
No description available.
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Wireless MEMS Accelerometer for Real-Time Small Laboratory Animal Activity MonitoringLu, Cheng-Kuan January 2008 (has links)
No description available.
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SILICON CARBIDE MEMS OSCILLATORPehlivanoglu, Ibrahim Engin January 2008 (has links)
No description available.
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