A surface-micromachined resonant-beam pressure-sensing structure

The first study on an entirely surface-micromachined resonant-beam pressure sensor is presented. Using a fully surface-micromachined process, an encapsulated beam resonant pressure-sensor structure with a pressure-sensitive diaphragm of 100/spl times/150/spl times/2 /spl mu/m has been fabricated. The resonating beam is fully enclosed inside the reference vacuum cavity formed beneath the diaphragm. The new design enables high pressure sensitivity and a miniature chip size, essential for sensors such as catheter-mounted intravascular blood pressure sensors. The pressure sensitivity is measured at 3.2%/bar with a beam resonance frequency of about 700 kHz.

[1]  K.D. Wise,et al.  Scaling limits in batch-fabricated silicon pressure sensors , 1987, IEEE Transactions on Electron Devices.

[2]  R. Hooke,et al.  Approximate Analysis of the Large Deflection Elastic Behaviour of Clamped, Uniformly Loaded, Rectangular Plates: , 1969 .

[3]  L. Tenerz,et al.  A fiberoptic silicon pressure microsensor for measurements in coronary arteries , 1991, TRANSDUCERS '91: 1991 International Conference on Solid-State Sensors and Actuators. Digest of Technical Papers.

[4]  Y. Haga,et al.  MICROMACHINED 125μm DIAMETER ULTRA MINIATURE FIBER-OPTIC PRESSURE SENSOR FOR CATHETER , 2000 .

[5]  Khalil Najafi,et al.  An ultraminiature CMOS pressure sensor for a multiplexed cardiovascular catheter , 1992 .

[6]  Miko Elwenspoek,et al.  Micro resonant force gauges , 1992 .

[7]  Kyoichi Ikeda,et al.  Various applications of resonant pressure sensor chip based on 3-D micromachining , 1999 .

[8]  Henry Guckel,et al.  Amplitude detecting micromechanical resonating beam magnetometer , 1998, Proceedings MEMS 98. IEEE. Eleventh Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Systems (Cat. No.98CH36176.

[9]  David W. Burns,et al.  Resonant microbeam strain transducers , 1991, TRANSDUCERS '91: 1991 International Conference on Solid-State Sensors and Actuators. Digest of Technical Papers.

[10]  L. Tenerz,et al.  The first surface micromachined pressure sensor for cardiovascular pressure measurements , 1998, Proceedings MEMS 98. IEEE. Eleventh Annual International Workshop on Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Systems (Cat. No.98CH36176.

[11]  David W. Burns,et al.  Sealed-cavity resonant microbeam pressure sensor , 1995 .

[12]  W. Ko,et al.  Development of a miniature pressure transducer for biomedical applications , 1979, IEEE Transactions on Electron Devices.