Nano-watt heatflux sensor considering contact resistance at thermopile junctions

Abstract

This paper presents design and fabrication procedures for nano-Watt resolution of heat flux sensor. To enhance the resolution, a contact resistance of thermopile is especially focused. CMOS (Complementary Metal-Oxide Semiconductor-compatible) process was used for deposition of gold and chromium which are composed of thermopile. The most important part of thermopile is the contact region of the junctions which generate electrical noises as well as thermoelectric power. The effect of contact conditions at junction point was investigated. The fabricated sensor has 100 thermocouples connected in series and its active junction is on the membrane which directly affects the sensitivity. Developed sensor system provides 0.0629V/nW of sensitivity and 1nW of high resolution. Copyright © 2011 by ASME.