A Novel Structure of Thermopile Infrared Detector with High Responsivity Based on CMOS Process

Abstract:

^{Superscript text}Thermopile-type Infrared detector is more and more popular in many fields, including infrared spectroscopy, radiometry, security systems and many consumer products. This paper reports a novel n-poly/p-poly thermopile suspension structure with four pairs of thermopiles that compatible with Complementary Metal-Oxide Semiconductor (CMOS) technology and its fill factor is larger than 90%. No additional material is needed to enhance infrared absorption since the passivation layer provided by the CMOS process is sufficient for certain infrared spectral bands. With the selected material parameters the optimal structure parameters are obtained after simulation. Through the theoretic calculation, this novel IR detector has good properties of high responsivity (larger than 1000V/W) and detectivity (larger than 1×108cm Hz1/2W-1) and low response time (shorter than 30ms).

• Periodical: Applied Mechanics and Materials (Volumes 271-272)
• Pages: 381-385
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.271-272.381
• Online since: December 2012
• Authors: Lei Sun, Wei Bing Wang, Xiao Yong Fang
• Keywords: CMOS Process, Infrared Detector, Thermopiles

References

[1] ROGALSKI, Infrared photon detectors, SPIE, Press, Bellingham, Washington USA (1995).

[2] J. Fonnollosa, M. Carmona, J. Santander, et al. Limits to the integration of filters and lenses on thermoelectric IR detectors by flip-chip techniques, Sensors and Actuators A 149 (2009) 65–73.

DOI: 10.1016/j.sna.2008.10.008

[3] S. Udina, M. Carmona, G. Carles, et al. A micromachined thermoelectric sensor for natural gas analysis: thermal model and experimental results, Sensors and Actuators B 134 (2008) 551–558.

DOI: 10.1016/j.snb.2008.05.043

[4] Rainer Buchner, Christoph Sosna, Marcus Maiwaid, et al. A high-temperature thermopile fabrication process for thermal flow sensors, Sensors and Actuators A 130–131 (2006) 262–266.

DOI: 10.1016/j.sna.2006.02.009

[5] Kum-Pyo Yoo, Nam-Ki Min, Fabrication of thin-film thermopile micro-bridge with XeF2 etching process, Thin Solid Films 516, 2008: 3586–3589.

DOI: 10.1016/j.tsf.2007.08.112

[6] LAHIJI G R, WISE K D. A batch-fabricated silicon thermopile infrared detector [J]. IEEE Trans ED (1982) 29(1): 14-22.

DOI: 10.1109/t-ed.1982.20652

[7] S.M. SZE, Semiconductor Sensors, New York: Wiley (1994).

[8] N. SCHNEEBERGER, O. PAUL, H. BALTES, Optimized structured absorbers for CMOS infrared detectors, in: Solid-State Sensors and Actuators (Transducers' 95, Eurosensors IX ); 648~651 (1995).

DOI: 10.1109/sensor.1995.721915

[9] N. SCHNEEBERGER, CMOS microsystems for thermal presence detection, PhD Thesis; ETH Zurich (1998).