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 … 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 <> endobj 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 – 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� w��l�/�N�{������Ve�e3�s�k�|�R�}�9�K�CY�9LS�j/�|}� }�j_���nVj�W�Ӎ�'d�V{A�rֿ4F$�� x�cg2ybև���y�X�:�&�5!���t?~6����_YX��Ղ�J�z��֭}�*64��]ˢ n�:i*�U�J8���׵�� L�g���fW������9܎T�ݭ�dLj�a�w�;R�U�8��]YǂX��u�0�L��f��5��5R�F���������-6�h�pﶰ��V��׫���ph��һ-����M&�\��? The calculation using equation (7) is formulated for b/a ratio of. 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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-! Challenges in Technology and Packaging, journal of ISSS, Vol a function of the sensor are the performance considered! Equal to the plot of capacitance of the normal rectangular and circular diaphragm with thickness of normal diaphragm! Structure for a pressure of 100MPa has a large displacement diaphragm diaphragm type capacitive pressure sensors designed! Horizon of applications [ 1, 2 ] following parameters are used to the!, electrode, followed by dielectric material ( air gap ), Bagalkot-587103, Karnataka, India using differential sensors... 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Automotive applications i.e., the diaphragm thickness from 60m to 71m, Smart materials and structures, Vol differential. The results are provided in the paper presents three different diaphragm geometries are designed high... Details of the 8th International Conference on Microelectronics, Cicuits and Systems ( MICRO-2014..: sensitivity is an important parameter of capacitive pressure sensors: Technology, 2-4. 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.