Yüncü, Hafit


Quality Factor Enhancement of Lateral Microresonators in Liquid Media by Hydrophobic Coating
Eroglu, Deniz; Külah, Haluk (Institute of Electrical and Electronics Engineers (IEEE), 2011-10-01)
In this letter, a new method of improving the quality factor of microresonators inside liquids is presented. By utilizing a conformally coated thin layer of parylene, which is highly hydrophobic, we trap air between the narrow gaps of a lateral resonator and prevent liquids from entering the gaps, thus preventing the viscous damping increase on the side surfaces. Initial tests with capacitive comb drives show that the quality factor decreases only threefold (from 157 to 55) when the device is operated in wa...
Hybrid connection of RF MEMS and SMT components in an impedance tuner
Unlu, Mehmet; Topalli, Kagan; Atasoy, Halil Ibrahim; Demir, Şimşek; Aydın Çivi, Hatice Özlem; Akın, Tayfun (Elsevier BV, 2010-01-01)
This paper presents a systematic construction of a model for a hybrid connected RF MEMS and SMT components in a reconfigurable impedance tuner. The double stub hybrid impedance tuner which employs a high number of MEMS switches is selected to demonstrate the feasibility of the connections. In the hybrid tuner, MEMS switches are actuated with DC bias signals, where SMT resistors de-couple RF from the DC lines. The hybrid tuner is realized in two steps, where the MEMS impedance tuner is fabricated on a glass ...
Active clamped ZVS forward converter with soft-switched synchronous rectifier for high efficiency, low output voltage applications
Acik, A; Cadirci, I (Institution of Engineering and Technology (IET), 2003-03-01)
The analysis, design, and implementation of an active clamped ZVS forward converter equipped with a soft-switched synchronous rectifier (ACFC-SR), proposed for high-efficiency low output voltage DC-DC converter applications, is presented. The converter efficiency is maximised due to soft switching of the main, active clamp, synchronous rectifier, and freewheeling MOSFET switches. The operating principles of the ACFC-SR are analysed in detail, and the converter performance is compared with that of alternativ...
Optimum Nyquist filters with controlled time and frequency characteristics
Tuncer, Temel Engin (Institution of Engineering and Technology (IET), 2002-10-10)
A design procedure is presented for pulse shaping filters based on the eigenfilter method. This method presents great flexibility for the control of the tail decay and stopband attenuation of the pulse shaping filters. A variety of optimum filters can be designed which are better than raised cosine filters both in time and frequency.
Ultrathick and high-aspect-ratio nickel microgyroscope using EFAB multilayer additive electroforming
Alper, Said Emre; Ocak, Ilker Ender; Akın, Tayfun (Institute of Electrical and Electronics Engineers (IEEE), 2007-10-01)
This paper presents a new approach for the development of a microgyroscope that has a 240-/mu m-thick multilayer electroformed-nickel structural mass and a lateral aspect ratio greater than 100. The gyroscope is fabricated using commercial multilayer additive electroforming process EFAB of Microfabrica, Inc., which allows defining the thickness of different structural regions, such as suspensions, proof mass, and capacitive electrodes, unlike many classical surface-micromachining technologies that require a...
Citation Formats
H. Yüncü and S. KAKAC, “THERMAL CONTACT CONDUCTANCE - THEORY AND APPLICATIONS,” 1993, vol. 258, Accessed: 00, 2020. [Online]. Available: