This paper presents an extensive review of optimization criteria of thermopile detector. The heat conductance and resistance of thermopile structure, the thermal-electric coefficient of thermocouple, and area of absorption layer are critical to the performance of thermopile. As a result, the critical features like responsivity and detectivity are widely considered and incorporated into a mathematical model in terms of the parameters like sheet resistance and width of polysilicon, length and number of thermocouple, area of radiation absorber, and geometric structures. The effect and correlation of these parameters are evaluated through this way. The design rule of CMOS compatible thermopile sensor is developed based on simulated conclusions. The optimized thermopile structures with responsivity higher than 100V/W, and specific detectivity better than 1 X 108cm(root)Hz/W can be derived. Finally, optimization criteria of thermopile detector is verified and discussed.
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