TY - JOUR
T1 - Characterization of miniaturized one-side-electrode-type fluid-based inclinometer
AU - Manaf, Asrulnizam Bin Abd
AU - Nakamura, Kazumasa
AU - Matsumoto, Yoshinori
N1 - Funding Information:
This work is supported in part by Grant-in-Aid for the Global Center of Excellence for High-Level Global Cooperation for Leading-Edge Platform on Access Spaces from the Ministry of Education, Culture, Sport, Science, and Technology in Japan. This research also is supported in part by Keio Gijuku Academic Development Fund. The VLSI chip in this study has been fabricated in the chip fabrication program of VLSI design and Education Center (VDEC), the University of Tokyo in collaboration between Rohm Corporation and Toppan Printing Corporation.
PY - 2008/5/28
Y1 - 2008/5/28
N2 - In this study, electrical double-layer theory is applied to realize a one-side-electrode-type fluid-based inclinometer combined with complementary metal oxide semiconductor (CMOS) circuitry. Substrate penetration lithography was applied in the fabrication of high-aspect-ratio SU-8 container molds, and molds with heights 1.0 mm were fabricated. Polydimethylsiloxane (PDMS) was used as the container material, and electrodes were fabricated on a ceramic substrate. Considering the electrical double-layer property, low surface tension, the dielectric constant and the problem of volatilization, methanol and propylene carbonate were tested as electrolytes. A charge-balanced capacitance-voltage (C-V) conversion circuit was designed as a detection circuit for this sensor and it was fabricated using 0.35 μm CMOS technology. The sensor part and detection circuit were integrated in one ceramic packaging for realize a miniaturization of inclination sensor system. To overcome the surface tension of the PDMS surface, silicone oil was injected in the container to cover the entire inner surface so that the movement of solution in the container became smooth. The linearity of the analog output of ±60° inclination for container dimensions of Ø 4.0 mm × 1.0 mm (diameter × thickness) was less than 6%/F.S. The minimum moving angle and response time were 0.4° and 0.9 s, respectively, when propylene carbonate was used as the electrolyte. The change in temperature did not affect the output voltage of the sensor between 0 and 50 °C. The effect of vibration was demonstrated in this paper.
AB - In this study, electrical double-layer theory is applied to realize a one-side-electrode-type fluid-based inclinometer combined with complementary metal oxide semiconductor (CMOS) circuitry. Substrate penetration lithography was applied in the fabrication of high-aspect-ratio SU-8 container molds, and molds with heights 1.0 mm were fabricated. Polydimethylsiloxane (PDMS) was used as the container material, and electrodes were fabricated on a ceramic substrate. Considering the electrical double-layer property, low surface tension, the dielectric constant and the problem of volatilization, methanol and propylene carbonate were tested as electrolytes. A charge-balanced capacitance-voltage (C-V) conversion circuit was designed as a detection circuit for this sensor and it was fabricated using 0.35 μm CMOS technology. The sensor part and detection circuit were integrated in one ceramic packaging for realize a miniaturization of inclination sensor system. To overcome the surface tension of the PDMS surface, silicone oil was injected in the container to cover the entire inner surface so that the movement of solution in the container became smooth. The linearity of the analog output of ±60° inclination for container dimensions of Ø 4.0 mm × 1.0 mm (diameter × thickness) was less than 6%/F.S. The minimum moving angle and response time were 0.4° and 0.9 s, respectively, when propylene carbonate was used as the electrolyte. The change in temperature did not affect the output voltage of the sensor between 0 and 50 °C. The effect of vibration was demonstrated in this paper.
KW - Capacitance sensor
KW - Electrical double layer
KW - Inclinometer
KW - SU-8
KW - Surface tensioning
UR - http://www.scopus.com/inward/record.url?scp=42949085616&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=42949085616&partnerID=8YFLogxK
U2 - 10.1016/j.sna.2008.01.003
DO - 10.1016/j.sna.2008.01.003
M3 - Article
AN - SCOPUS:42949085616
VL - 144
SP - 74
EP - 82
JO - Sensors and Actuators A: Physical
JF - Sensors and Actuators A: Physical
SN - 0924-4247
IS - 1
ER -