Pirani Vacuum Gauges Using Silicon-on-Glass and Dissolved-Wafer Processes for the Characterization of MEMS Vacuum Packaging

Topalli, Ebru Sagiroglu
Topalli, Kagan
Alper, Said Emre
Serin, Tulay
Akın, Tayfun
This paper presents the design and implementation of Pirani vacuum gauges for the characterization of vacuum packaging of microelectromechanical systems (MEMS). Various Pirani vacuum gauges are fabricated with two different standard in-house fabrication processes, namely the silicon-on-glass (SOG) process and dissolved-wafer process (DWP). The Pirani gauges utilize meander-shaped suspended silicon coils as the heaters and two isolated silicon islands in the close proximity of the heater that function as dual-heat sinks to enhance the sensitivity and dynamic range as compared to a microbridge with a single heat sink. The gauges are designed to occupy an area of 4 mm x 1.5 mm. The DWP Pirani gauge fabricated with a structural thickness of 14 mu m and a gap of 2 mu m shows a measured sensitivity of 4.2 x 10(4) (K/W)/Torr in a dynamic range of 10-2000 mTorr. The SOG Pirani gauge fabricated with a structural thickness of 100 mu m and a gap of 3 mu m shows a lower measured sensitivity of 3.8 x 10(3) (K/W)/Torr in a dynamic range of 50-5000 mTorr; however, the 100 mu m-thick structural layer results in a much more robust process against stress-based deformations in suspended silicon compared to the DWP Pirani gauges. Each gauge is used to monitor the pressure of a different packaging approach. The DWP Pirani gauge is used to detect the pressure of a wafer-level vacuum package, where the pressure inside the cavity is measured to be about 2.4 mTorr. The SOG Pirani gauge is used the monitor the pressure inside a hybrid platform package which is vacuum-sealed using a projection welder, where the pressure is measured to be about 1400 mTorr. These measurements verify that the DWP and SOG Pirani gauges can be used for the characterization of wafer-level or hybrid platform vacuum packages for MEMS devices.


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Comart, Ilker; Topalli, Kagan; Demir, Şimşek; Akın, Tayfun (Institute of Electrical and Electronics Engineers (IEEE), 2014-06-01)
This paper presents the microwave characterization of a wafer level packaging approach for RF MEMS devices, using glass frit as the bonding material. Coplanar waveguide transmission lines are packaged by silicon caps to carry out the RF characterization of the package structure. Prior to bonding of the cap on the transmission lines, cap wafers are bulk micromachined to form the cavities for housing the device to be packaged and pad windows to access the RF ports of the devices. Lateral feedthroughs are desi...
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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 ...
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Torrents, A.; Azgın, Kıvanç; Godfrey, S. W.; Topalli, E. S.; Akın, Tayfun; Valdevit, L. (IOP Publishing, 2010-12-01)
This paper presents the design, optimization and manufacturing of a novel micro-fabricated load cell based on a double-ended tuning fork. The device geometry and operating voltages are optimized for maximum force resolution and range, subject to a number of manufacturing and electromechanical constraints. All optimizations are enabled by analytical modeling (verified by selected finite elements analyses) coupled with an efficient C++ code based on the particle swarm optimization algorithm. This assessment i...
All 3-D Printed Free-Space Setup for Microwave Dielectric Characterization of Materials
Hajisaeid, Ehsan; Dericioğlu, Arcan Fehmi; Akyurtlu, Alkim (Institute of Electrical and Electronics Engineers (IEEE), 2018-08-01)
In this paper, the development of an all 3-D printed wide band (2-18 GHz) free-space measurement system for characterizing the complex dielectric properties of flexible as well as rigid materials was demonstrated. Each part of the setup was designed and simulated precisely to show the effect of the 3-D printed quasi-optical lenses placed in front of the wide band ridged horn antennas on the beam and radiation pattern. More than 10 parts of the setup were 3-D printed using two different 3-D printers, and the...
Terahertz Bandpass Frequency Selective Surfaces on Glass Substrates Using a Wet Micromachining Process
Ramzan, Mehrab; Khan, Talha Masood; Bolat, Sami; NEBİOĞLU, Mehmet Ali; Altan, Hakan; Okyay, Ali Kemal; Topalli, Kagan (Springer Science and Business Media LLC, 2017-08-01)
This paper presents terahertz (THz) frequency selective surfaces (FSS) implemented on glass substrate using standard microfabrication techniques. These FSS structures are designed for frequencies around 0.8 THz. A fabrication process is proposed where a 100-mu m-thick glass substrate is formed through the HF etching of a standard 500-mu m-thick low cost glass wafer. Using this fabrication process, three separate robust designs consisting of single-layer FSS are investigated using high-frequency structural s...
Citation Formats
E. S. Topalli, K. Topalli, S. E. Alper, T. Serin, and T. Akın, “Pirani Vacuum Gauges Using Silicon-on-Glass and Dissolved-Wafer Processes for the Characterization of MEMS Vacuum Packaging,” IEEE SENSORS JOURNAL, pp. 263–270, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43094.