International Journal of Computational Engineering ScienceVol. 04, No. 03, pp. 493-496 (2003) Fabrication Process/Fabrication TechniqueNo AccessA NOVEL Z-AXIS ACCELEROMETER WITH PERFECTLY-ALIGNED, FULLY-OFFSET VERTICAL COMBS FABRICATED USING THE EXTENDED SACRIFICIAL BULK MICROMACHINING PROCESSDONGIL (DAN) CHO, HYOUNGHO KO, JONGPAL KIM, SANGJUN PARK, DONGHUN KWAK, TAEYONG SONG, WILLIAM CARR, and JAMES BUSSDONGIL (DAN) CHOSchool of Electrical Engineering, Seoul National University, San 56-1, ShilimDong, Gwanak Gu Seoul, KoreaCorresponding author. Search for more papers by this author , HYOUNGHO KOSchool of Electrical Engineering, Seoul National University, San 56-1, ShilimDong, Gwanak Gu Seoul, Korea Search for more papers by this author , JONGPAL KIMSchool of Electrical Engineering, Seoul National University, San 56-1, ShilimDong, Gwanak Gu Seoul, Korea Search for more papers by this author , SANGJUN PARKSchool of Electrical Engineering, Seoul National University, San 56-1, ShilimDong, Gwanak Gu Seoul, Korea Search for more papers by this author , DONGHUN KWAKSchool of Electrical Engineering, Seoul National University, San 56-1, ShilimDong, Gwanak Gu Seoul, Korea Search for more papers by this author , TAEYONG SONGSchool of Electrical Engineering, Seoul National University, San 56-1, ShilimDong, Gwanak Gu Seoul, Korea Search for more papers by this author , WILLIAM CARRNew Jersey Microsystems, Inc., Newark, NJ, U.S.A. Search for more papers by this author , and JAMES BUSSOffice of Naval Research, Arlington, VA, U.S.A. Search for more papers by this author https://doi.org/10.1142/S1465876303001599Cited by:3 PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail AbstractThis paper presents a novel z-axis accelerometer with perfectly aligned vertical combs fabricated using the Extended Sacrificial Bulk Micromachining (ESBM) process. The z-axis accelerometer is fabricated using only one (111) SOI wafer and two photo masks without wafer bonding or CMP processes as used by other research efforts that involve vertical combs. In our process, there is no misalignment in lateral gap between the upper and lower comb electrodes, because all critical dimensions including lateral gaps are defined using only one masks. The fabricated accelerometer has the structure thickness of 40 μm, the vertical offset of 15 μm, and lateral gap between electrodes of 4 μm. Torsional springs and asymmetric proof mass produce a vertical displacement when an external z-axis acceleration is applied, and capacitance change due to the vertical displacement of the comb is detected by charge-to-voltage converter. The signal-to-noise ratio of the modulated and demodulated output signal is 80 dB and 76.5 dB, respectively. The noise equivalent input acceleration resolution of the modulated and demodulated output signal is calculated to be 500 μg and 748 μg. The scale factor and linearity of the accelerometer are measured to be 1.1 mV/g and 1.18 % FSO, respectively. The measured bandwidth is more than 100 Hz.Keywords:z-axis accelerometerprefectly aligned vertical combsESBM process References A. M. Madniet al., Intelligent Robots and Systems 3, 1389 (1998). Google ScholarH. Jeonget al., Transducers'99 1066 (1999). Google ScholarR. A. Conantet al., A flat highfrequency scanning mirror (Hilton Head, 2000) pp. 6–9. Google Scholar Arjun Selvakumar, Farrokh Ayazi and Khalil Najafi, "A high sensitivity z-axis torsional silicon accelerometer", International Electron Devices Meeting(1996) . Google Scholar A. Hanneborg, "Silicon wafer bonding techniques for assembly of micromechanical elements", Micro Electro Mechanical Systems(1991) 92-98 . Google ScholarJ. Kim, S. Park and D. Cho, Sensors and Actuators A 1, 653 (2002). Google Scholar FiguresReferencesRelatedDetailsCited By 3164 nW Inverter-based capacitive readout IC for microaccelerometerYoungwoon Ko, Hyungseup Kim, Yeongjin Mun, Byeoncheol Lee and Dong-il Dan Cho et al.23 January 2018 | Microsystem Technologies, Vol. 25, No. 5Reconfigurable Sensor Analog Front-End Using Low-Noise Chopper-Stabilized Delta-Sigma Capacitance-to-Digital ConverterHyungseup Kim, Byeoncheol Lee, Yeongjin Mun, Jaesung Kim and Kwonsang Han et al.10 July 2018 | Micromachines, Vol. 9, No. 7Highly configurable capacitive interface circuit for tri‐axial MEMS microaccelerometerHyoungho Ko1 Jul 2012 | International Journal of Electronics, Vol. 99, No. 7 Recommended Vol. 04, No. 03 Metrics History Keywordsz-axis accelerometerprefectly aligned vertical combsESBM processPDF download