April 27, 2006

CMOS Compatible MicroElectroThermal Devices and their Application in Uncooled IR Imaging

Eran Socher, Department of Electrical Engineering, Technion - Israel Institute of Technology, Haifa, Israel

Abstract: The design of arrays of small, highly sensitive, integrated uncooled sensors is one of the major challenges of micromachining and thermal imaging. The micromachining and MEMS revolution enables the realization of low thermal mass structures highly thermally - isolated integrated in VLSI chips. This integration leads the way to arrays of sensitive uncooled IR sensors integrated on the same chip with their readout and control electronics.

In this talk several novel devices applicable for use as uncooled micro-size thermal sensors will be discussed. The temperature sensitive electro-thermal behavior is explored and so are the ways to exploit it in the best way to realize the sensors.

Sensor mechanical modeling

Novel spiral thermoelectric sensors and arrays are modeled and realized in a new CMOS compatible technology along with CMOS readout circuitry and achieve better results than previous thermoelectric sensors. Serpentine distributed microbolometers and arrays are investigated and realized in similar CMOS compatible technology along with CMOS circuits for readout and novel concepts of self heating compensation. The electro-thermal stability of distributed and lumped suspended structures is investigated and generalized, applying new algorithms to improve modeling convergence. Another new approach for thermal sensing that is presented is the temperature sensitive MOS (TMOS). Realized in CMOS-SOI technology, such devices achieve temperature sensitivity exceeding 4%/K in subthreshold, which is twice as achieved in state-of-the-art microbolometers. Future prospects for millimeter-wave radiation detection using antenna-coupled microbolometers will also be discussed.

About the speaker: Eran Socher was born in Tel Aviv, Israel, on December 12, 1975. He holds a B.Sc degree in electrical engineering, a B.A. degree in physics (both Summa Cum-Laude) an M.Sc and a Ph.D in electrical engineering (2005), all from the Technion - Israel Institute of Technology, Haifa, Israel. He is now working in an IDF research unit and lecturing at the Technion and Bar-Ilan University.

His research focuses on analysis, optimal design, fabrication and characterization of micromachined integrated electro-thermal devices, especially for uncooled IR sensing applications. Other fields of interest are micromachined inertial sensors, analog and mixed-signal interface circuits for microsystems, RF-MEMS and fundamental noise phenomena in microsystems.


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