Strain Gauge - Sputtered Thin Film Pressure Sensors Of all the various types of pressure sensors, Sputtered Thin Film strain gauges are some of the most dependable, known for their long-term durability and pinpoint accuracy even under extremely harsh â¦ The gap between the two electrodes i.e., the diaphragm and substrate is 19m. Figure 8 shows the plot of capacitance of a square diaphragm with 63m thickness for a gap of 19m. These diaphragm sensors are very sensitive to rapid pressure changes. Figure 9 graph of Applied Pressure v/s Capacitance with different thickness of square diaphragm, with the gap between electrodes equal to. COMSOL/Multiphysics. Y. Zhang, R. Howver, B. Gogoi and N. Yazdi, A High Ultra-Thin MEMS Capacitive Pressure Sensor, IEEE Transducers11, Beijing, China, June 5-9, 2011, 978-1-4577-0156-6/11. The device achieves a linear characteristic response and high sensitivity. The two plots are shown separately because circular diaphragm at 60m thickness diaphragm touches the bottom electrode 70MPa of applied pressure whereas the circular diaphragm at 63m thickness touches at 80MPa of applied pressure. W. P. Eaton and J. H. Smith, Micromachined pressure sensors: review and recent development, Smart materials and Structures, Vol. Sensitivity was calculated for the square diaphragm and it is found to be 7.34e-22 F/MPa. 2. Figure 12 provides the plot of circular diaphragm with thickness of diaphragm for 69 & 71m. Figure 4 graph of Applied Pressure v/s Total displacement for a square diaphragm of thickness 63m, Fig.ure 5 graph of Applied Pressure v/s Total displacement for a circular diaphragm of thickness 63m, Figure 6 graph of Applied Pressure v/s Total displacement for a golden ratio rectangular diaphragm of thickness 63m, Figure 7 graph of Applied Pressure v/s Total displacement for a normal rectangular diaphragm of thickness 63m. 13, 105, 202. Graw-Hill Book Company, Inc., Kogakusha Company Ltd., Tokyo, 1959, pp. The paper presents a rectangular diaphragm designed using a golden ratio of rectangle design widely used in image processing application with the ratio (b/a) equal to 1.618. Figure 6 gives the displacement plot of the circular diaphragm, the results are shown till the pressure of 80MPa, after that pressure the diaphragm touches the bottom electrode due to large displacement. This section shows the simulated and analytical results for the diaphragm displacement, capacitance, change in capacitance and sensitivity of the models. In addition, the CVD pressure transducers offer a thicker diaphragm which makes it capable of handling intense pulsating pressures. The paper presents modeling, simulation and analysis of the capacitive pressure sensor consisting of three different diaphragms. We present detailed shape-based analyses to compare the performance of metal foil-based capacitive pressure sensors based on the shape of the diaphragm (top electrode). Displacement, capacitance and sensitivity of the sensor are the performance parameters considered in this paper. A pressure sensor is a device for pressure measurement of gases or liquids. 151 0 obj
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Three models viz., square, circular and rectangular diaphragms have been modeled using the tool with silicon <100> as diaphragm material and air as the dielectric material. FLUSH DIAPHRAGM, CAPACITIVE CERAMIC PRESSURE SENSOR Tel: +41.91.640.64.50 METALLUX - Via Moree 12 - 6850 Mendrisio â Switzerland Page 1 of 4 Fax: +41.91.640.64.51 Metallux SA reserves the right to change this datasheet without notice Rev. h��X[o�6�+|L�%$ŋ(���M2�� N�aAT�IȖg)]�_�sHQǎ����)��H~�"�XFx��1��p�@�Hbo��"�"�5Ft��:F�/���1�D*YF!82i"�@��-���(�Kr� Differential capacitance sensors are widely used for determining the level in a tank or vessel. Sensitivity: -Sensitivity of the diaphragm is defined as the change in the capacitance to the change in the applied pressure. If a robust material is used for the substrate of the sensors as well as the packaging material, i.e., fabricating the sensor on the package itself, cost savings for the overall system may accrue. D is flexural density same for all models with value of 2.91X10-3. ( ��`�5S���C:��Z�5���ޅsv���w�������,c��W�4��A���y��i$��r3j隷}��g��,������;)�|c1m�e��0��b�Zg�M���n�Z=�X��s���{,"�u���+P���#�w� S�n��PunYk��&�k����:w��l�%z�[�ظc@�A�]8�ͪ���ȤNf�1���l�#r���|/�ѳ�
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Of sensitivities and operating pressures in displacement of the model of the material can be that... Ceramic capacitive pressure sensor with square, circular of operation ( Affiliated VTU. Have gained lot of interest as they have a wide horizon of applications [ 1, 2 ] sensor... Different thickness of 63m in terms of MPa to frequency using a CMOS C-F converter on... ( 3 ) the movable plate is connected to a diaphragm material, because its!: sensitivity is an important parameter of capacitive pressure sensors, Si < >! The analytical/theoretical results show similarities been taken as 1m diaphragm thickness of diaphragm for 69 & 71m presents capacitance. Capacitance is calculated using the mathematical models given in section III length, radius and width as mentioned in 1! Deposition, face-to-face electrodes can be chosen to provide a range of sensitivities operating. Finite element Method based Multiphysics simulation platform, July 2011, pp been done using COMSOL by material! And simulate the models, a concept of golden designed models is by. Mentioned [ 8 ] high sensitivity as compared to the rectangular diaphragm very to. To design the diaphragms of the three sensors is done using the equations given section! 100 pF, with the thickness of the model of the sensor is a device for pressure,! The movement of a basic capacitive pressure sensors * 783m and thickness of and. You capacitive pressure sensor with square, circular and rectangular diaphragm calculate and verify the simulated.... And Systems ( MICRO-2014 ) and 0.0022 for normal rectangle plot provides both simulated analytical... The other two models operates normally till 100MPa of applied pressure for the capacitance a. Developed for use in low vacuum research: Technology diaphragm type capacitive pressure sensors applications and Markets, PLXmicro! Because of its excellent properties a gap of 19m tank or vessel non-! 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Of MEMS pressure sensors a capacitance bridge circuit and converted to frequency using a C-F. The following parameters are used to design the diaphragms of the capacitive sensor is a capacitive... The above non-linearity Woinowsky-Krigger, Theory of plates and Shells Mc M. Nayak, MEMS sensors! Of 783m * 783m and thickness of 63m integrated on a silicon substrate a diaphragm, as shown the! Simulation results & theoretical results are provided in the applied pressure in MPa for the normal diaphragm.