Overview of Prof. Yael Nemirovsky MEMS Activity in the Microelectronics Research Center, Dept. of Electrical Engineering, Technion-Israel Institute of Technology

Y. Nemirovsky, May 2000

Our work focuses on CMOS compatible micromachined microsystems.


 

We are either pursuing monolithic systems or using indium-bumps technology and flip chip bonding to integrate CMOS chips with silicon bulk micromachined chips.

 
Our research is directed towards several types of generic MEMS:
 


 

(I) Inertial sensors-accelerometers and gyroscopes
We are doing research on a novel approach to Coriolis Vibrating Gyroscopes and accelerometers that are based on novel integrated optical based motion sensing techniques.

 
First generation of Inertial sensors were based on the Modulated Integrated Differential Optical Sensing (MIDOS) method. There is a patent pending on this novel concept (in collaboration with Rafael) and several prototypes have been fabricated and demostrated. Currently RAFAEL are working towards a product based on these prototypes.
Second generation of Inertial sensors are currently being studied. These are based on a advance method of the MIDOS concept, referred to as Enhanced-MIDOS (EMIDOS), also having a patent pending. This version can yield inertial sensors with higher performances than the first generation.

Several papers describe some of this work:
1)O. Degani, D. J. Seter, E. Socher, S. Kaldor and Y. Nemirovsky, "Micromachined Accelerometer with Modulated Integrative Differential Optical Sensing", IEE -Electronics Letters, Vol. 34, No. 7, 2nd April 1998, pp. 654-655.
2)O. Degani, D.J. Seter, E. Socher, S. Kaldor and Y. Nemirovsky, "Optimal Design and Noise Considerations of Micromachined Vibrating Rate Gyroscope with Modulated Integrative Differential Optical Sensing", IEEE - Journal of Microelectromechanical Systems, Vol. 7, No.3, September 1998, pp. 329-338.
3)D.J. Seter, O. Degani, E. Socher, S. Kaldor, E. Scher and Y.Nemirovsky, "Charcterization of a Novel Micromachined Optical Vibrating Rate-Gyroscope", AIP – Review of Scientific Instruments, Vol. 70, No. 2, February 1999, pp. 1274-1276.
4)Ofir Degani, Dan J. Seter, Eran Socher and Yael Nemirovsky, "Comparative study of novel micromachined accelerometers employing MIDOS", Sensors and Actuators A: Physical, Vol. 80, 2000, pp. 91-99.
5)Ofir Degani, Dan J. Seter, Eran Socher and Yael Nemirovsky, "A novel micromachined vibrating rate-gyroscope with optical sensing and electrostatic actuation", Sensors and Actuators A: Physical, Vol. 83 (2000), pp. 54-60.
6)Ofir Bochobza-Degani, Dan J. Seter, Eran Socher and Yael Nemirovsky, "Design and Noise Consideration of an Accelerometer employing modulated integrative differential optical sensing", Sensors and Actuators A: Physical, Vol. 84 (2000), pp. 53-64.
7)a related paper is: Y. Nemirovsky, P. Muralt and N. Setter, ``Design of a Novel Thin Film Piezoelectric Accelerometer'', Sensors and Actuators, A56, pp. 239–249, (1996).
The work has been partially presented in several conferences:
8)D. J. Seter, O. Degani, S. Kaldor, E. Scher, J. Rosenberg and Y.Nemirovsky, "Microelectromechanical Vibrating Inertial Sensors with Integrated Optical Sensing", Proceeding of GYRO-Technology Symposium, Stuttgart, Germany, 15-16 September 1998, pp. 10.0-10.13.
9)O. Degani, D.J. Seter, E. Socher, S. Kaldor, E. Scher and Y. Nemirovsky, "Comperative Study of Novel Accelerometers employing MIDOS", Proc. of IEEE - MEMS' 99, Orlando, USA, 17-21 January 1998, pp. 66-71.
10)O. Degani, D.J. Seter, E. Socher, S. Kaldor, E. Scher and Y. Nemirovsky, "Optically Sensed Cantilever Suspended Micromachined Inertial Sensor", Proc. of AGIL 98, Ramat-Gan, Israel, 25-26 November 1998, p. 40.
11)O. Bochobza-Degani, D. J. Seter, E. Socher and Y. Nemirovsky, “A Novel Micromachined Vibrating Rate Gyroscope with Optical Sensing and Electrostatic Actuation”, Tech. Dig. International Conf. Solid-State Sensors and Actuators (Transducers’99), Sendai, Japan, 7-10 June 1999.

 
ISFET catheter for brain monitoring

 

ISFET sensor in the catheter for brain Monitoring

 
(II) Micromachined Thermal and IR Sensors
We are pursuing research on CMOS compatible monolithic micromachined arrays of thermal sensors for various IR applications. There is collaboration with Siemens on pyroelectric detectors. At Technion we focus on thermoelectric sensors. We have developed a unique optimal design approach and have fabricated working prototypes. The following papers describe some of the results.
1)E. Socher, O. Degani and Y. Nemirovsky, "Optimal Design and Noise Considerations of CMOS Compatible IR Thermoelectric Sensors", Sensors and Actuators A -Physical, Vol. 71, No. 1-2, November 1998, pp.107-115.
2)E. Socher, O. Degani and Y. Nemirovsky, “Optimal Performance of CMOS Compatible IR Thermoelectric Sensors”, Journalof Microelectromechanical Systems, Vol. 9(1), pp. 38–46.
3)The work has been partially presented in the following conference:
4)E. Socher, O. Degani and Y. Nemirovsky, "Integrated Uncooled Micromachined Far-Infra-Red Thermoelectric Sensors for Thermal Imaging", Proc. of AGIL 98, Ramat-Gan, Israel, 25-26 November 1998, p. 78.
5)E. Socher, O. Bochobza-Degani, and Y. Nemirovsky, “Investigation of Integrated Micromachined Uncooled thermoelectric Sensors for Imaging Applications”, Tech. Dig. International Conf. Solid-State Sensors and Actuators (Transducers’99), Sendai, Japan, 7-10 June 1999.
 
(III) Theoretical issues and phenomena in Micromachined Actuators 
In this research program we intend to investigate and study the unike properties of electrostatic and magnetostatic actuators. We develop new methods and modeling approches for physical phenomena related with actuators such as: Pull-In, Dynamic Pull-In and more.
The following papers describe some of the initial results:
1)O. Degani, E. Socher, A. Lipson, T. Lietner, D. J. Setter, S. Kaldor and Y. Nemirovsky, "Pull-in Study of an Electrostatic Torsion Micro-Actuator", IEEE - Journal of Microelectromechanical Systems, Vol. 7, No. 4, December 1998, pp. 373-379.
2)Y. Nemirovsky and O. Degani, “A Methodology and Model for the Pull-In parameters of Electrostatic Actuators”, submitted to JMEMS, January 2001.
The work has been partially presented in the following conference:
1)O. Bochobza-Degani, D. J. Seter, E. Socher and Y. Nemirovsky, ”A generalized Pull-In condition in micromachined electrostatic actuators with a single degree of freedom”, AISEM’2000, Lecce, Italy, February 12-15, 2000.
2)O. Degani, E. Socher, Y. Yaniv and Y. Nemirovsky, “Modeling the Pull-In parameters of electrostatic actuators with a novel lumped two degrees of freedom pull-in model”, to be presented at Transducers’01/EurosensorsXV conf., Munich, June, 2001.
3)O. Degani and Y. Nemirovsky, “On the effect of residual charges on the pull-in parameters of electrostatic actuators”, to be presented at Transducers’01/ EurosensorsXV conf., Munich, June, 2001.


(IV) Micromachining Technology

We are pursuing several aspects of micromachining technology. The following publication demonstrates our methodology and approach:

1)Y. Nemirovsky and A. El– Bahar, ``The Non Equilibrium Band Model of Silicon in TMAH and in Anisotropic Electrochemical Alkaline Etching Solutions'', Sensors and Actuators, 75, pp. 205–214 (1999).

(V) CMOS VLSI Analog Design

A related part of the research focuses on low noise analog design, as indicated by the following publications:

1)C.G. Jakobson, I. Bloomand Y. Nemirovsky, “1/f Noise in CMOS Transistors for Analog Applications fromSubthreshold to Saturation”, Solid State Electronics, 42(10), 1807-1817 (1998).

2)C.G. Jakobson and Y. Nemirovsky, “``CMOS Low Noise Switched Charge Sensitive Preamplifier for CdTe and CdZnTe X– Ray Detectors'', IEEE Trans. on Nuclear Science, 44(1), pp. 20–25, (1997).

3)Y. Nemirovsky, Igor Brouk and C.G. Jakobson, “1/f Noise in CMOS Transistors for Analog Applications”, submitted to IEEE Trans. on Electron Devices (2000).

The work has been presented in several conferences.
(VI) Micomachined Ion Selective Field Effect Transistors and BioFets
We are pursuing research on MIMOS-Micromachined Ionic MosFets for mainly Biomedical applications.
The following papers summarize some of the results:
1)C.G. Jakobson and Y. Nemirovsky, “1/f Noise in ISFETs from Subthreshold to Saturation”, IEEE Trans. on Electron Devices, January (1999).
2)C.G. Jakobson, Y. Nemirovsky and M. Feinsod, “Low Frequency Noise and Drift in Ion Sensitive Field Effect Transistors”, to be published in Sensors & Actuators (2000).