Mems gyroscopes for tactical-grade inertial measurement applications

Alper, Said Emre
This thesis reports the development of high-performance symmetric and decoupled micromachined gyroscopes for tactical-grade inertial measurement applications. The symmetric structure allows easy matching of the resonance frequencies of the drive and sense modes of the gyroscopes for achieving high angular rate sensitivity; while the decoupled drive and sense modes minimizes mechanical cross-coupling for low-noise and stable operation. Three different and new symmetric and decoupled gyroscope structures with unique features are presented. These structures are fabricated in four different micromachining processes: nickel electroforming (NE), dissolved-wafer silicon micromachining (DWSM), silicon-on-insulator (SOI) micromachining, and silicon-on-glass (SOG) micromachining. The fabricated gyroscopes have capacitive gaps from 1.5æm to 5.5æm and structural layer thicknesses from 12æm to 100æm, yielding aspect ratios up to 20 depending on the fabrication process. The size of fabricated gyroscope chips varies from 1x1mm2 up to 4.2x4.6mm2. Fabricated gyroscopes are hybrid-connected to a designed capacitive interface circuit, fabricated in a standard 0.6æm CMOS process. They have resonance frequencies as small as 2kHz and as large as 40kHz; sense-mode resonance frequencies can be electrostatically tuned to the drive-mode frequency by DC voltages less than 16V. The quality factors reach to 500 at atmospheric pressure and exceed 10,000 for the silicon gyroscopes at vacuum. The parasitic capacitance of the gyroscopes on glass substrates is measured to be as small as 120fF. The gyroscope and interface assemblies are then combined with electronic control and feedback circuits constructed with off-the-shelf IC components to perform angular rate measurements. Measured angular rate sensitivities are in the range from 12æV/(deg/sec) to 180æV/(deg/sec), at atmospheric pressure. The SOI


Hamilton-Jacobi theory of continuous systems
Güler, Y. (Springer Science and Business Media LLC, 1987-8)
The Hamilton-Jacobi partial differnetial equation for classical field systems is obtained in a 5n-dimensional phase space and it is integrated by the method of characteristics. Space-time partial derivatives of Hamilton’s principal functionsS μ (Φ i ,x ν ) (μ,ν=1,2,3,4) are identified as the energy-momentum tensor of the system.
Deep-trench RIE optimization for high performance MEMS microsensors
Aydemir, Akın; Turan, Raşit; Department of Physics (2007)
This thesis presents the optimization of deep reactive ion etching process (DRIE) to achieve high precision 3-dimensional integrated micro electro mechanical systems (MEMS) sensors with high aspect ratio structures. Two optimization processes have been performed to achieve 20 μm depth for 1 μm opening for a dissolved wafer process (DWP) and to achieve 100 μm depth for 1 μm opening for silicon-on-glass (SOG) process. A number of parameters affecting the etch rate and profile angle are investigated, including...
Development of atomic force microscopy system and kelvin probe microscopy system for use in semiconductor nanocrystal characterization
Bostancı, Umut; Turan, Raşit; Department of Physics (2007)
Atomic Force Microscopy (AFM) and Kelvin Probe Microscopy (KPM) are two surface characterization methods suitable for semiconductor nanocrystal applications. In this thesis work, an AFM system with KPM capability was developed and implemented. It was observed that, the effect of electrostatic interaction of the probe cantilever with the sample can be significantly reduced by using higher order resonant modes for Kelvin force detection. Germanium nanocrystals were grown on silicon substrate using different g...
Development of software for calculations of the reflectance, transmittance and absorptance of multilayered thin films
Şimşek, Yusuf; Esendemir, Akif; Department of Physics (2008)
The aim of this study is to develop a software which calculates reflection, transmission and absorption of multilayered thin films by using complex indices of refraction, as a function of both wavelength and thickness. For these calculations matrix methods will be considered and this software is programmed with the matrix method. Outputs of the program will be compared with the theoretical and experimental results studied in the scientific papers.
Multi-band polarization independent cylindrical metamaterial absorber and sensor application
Dincer, Furkan; KARAASLAN, MUHARREM; Colak, Sule; TETİK, ERKAN; AKGÖL, OĞUZHAN; ALTINTAŞ, OLCAY; Sabah, Cumali (World Scientific Pub Co Pte Lt, 2016-03-30)
A multi-band perfect metamaterial absorber (MA) based on a cylindrical waveguide with polarization independency is numerically presented and investigated in detail. The proposed absorber has a very simple configuration, and it operates at flexible frequency ranges within the microwave frequency regime by simply tuning the dimensions of the structure. The maximum absorption values are obtained as 99.9%, 97.5%, 85.8%, 68.2% and 40.2% at the frequencies of 1.34 GHz, 2.15 GHz, 3.2 GHz, 4.31 GHz and 5.41 GHz, re...
Citation Formats
S. E. Alper, “Mems gyroscopes for tactical-grade inertial measurement applications,” Ph.D. - Doctoral Program, Middle East Technical University, 2005.