This paper presents an extensive experiment results of measuring properties of thermopile detector produced by CMOS compatible process and front-side Si bulk etching. The thermoelectric materials used are n- polysilicon and aluminum. Several parameters of thermopile detectors, such as width of polysilicon, length of thermopile, number of thermocouple, overlap length of hot junction into absorber area, and area of absorption layer are investigated in this study. Any physical characteristics of thermopile detectors, such as responsivity and detectivity of each device are measured as well. The heat conductance, resistance of thermopile structure, and the thermal-electric coefficient of thermocouple are critical to the performance of thermopile. All of them will affect the characters of sensor. In general case, a trade-off relation is among these parameters. When we design thermopile devices, we must consider these issue and determine a set of optimized parameters. In our investigation, the relation of each parameter and the device characters are measured. And the effect and correlation of these parameters versus thermopile property are evaluated. Based on these experiment results we can know the operation mechanism and correlation effect of these parameters. Establishment of accurate model for thermopile helps us to design an optimized device for various applications.
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