采用环形岛棱结构的电容式压力传感器英文.PDF

17 6 Vol. 17 No. 6 2009 6 Optics and Precision Engineering Jun. 2009 1004-924X( 2009) 06- 1385-06 邹黎明, 郭 航 ( 厦门大学 萨本栋微机电研究中心, 福建厦门361005) : MEMS , LPCVD , PECV D , , , , , , , 48. 38% , 1. 6% : 微机电系统; 电容式压力传感器; 线性度; 有限元法 : T P212. 12 : A Capacitive pressure sensor with circular island structure ZOU L-i ming, GUO Hang (P en-T ung Sah MEM S Research Center, X iamen University , X iamen 361005, China) Abstract: A capacitive pressur e sensor w ith a new movable electric plate structure is presented to im- prove the output nonlinearit of a M EMS-based capacitive pressure sensor. T he movable plate of the sensor is a rectangular memrance made of LPCVD silicon nitride film , and a circular island is added from the center to the edge of the membrane b depositing and patterning a la er of PECVD silicon di- oxide. With this structure, the deformation of the movable plate of the capacitive pressure sensor w ill tend to flat w hen appl ing a load of pressure, so that the nonlinearit of stra capacitance near the edge of the entire structur e is decreased and the output properties of the sensor is improved. Moreo- ver, the Finite Element M odel( FEM) in ANSYS is used to anal ze the new structure of the movable electr ical plate w ith different dimensions to obtain the relationship between deflection and pressure and the corr esponding stress distribution and a curve fitting based on the least-square method is applied to calculate the output linearit of the sensor. Comparison of the M EM S-based capacitive pressur e sensor w ith a general structur e sensor, the output