High-detectivity Infrared Detector Based on Dual-layer Thermopile

摘要

This paper presents a high-detectivity micromachined infrared detector based on dual-layer thermopile. The dual-layer thermopile was designed by using n/p-polysilicon on beams radially distributed on the surface of the support layer. The absorber made by black silicon was released by dry etching of polysilicon using XeF2. The etch-stop structure was designed to prevent the damage of the detector caused by isotropic etching. We simulated the thermal conduction of the detector in steady state and in transient state, respectively. The results indicated that the presented thermopile detector performed a responsivity of 179.3 V/W, a detectivity of 2.99×10^{8cm·Hz1/2/W and a time constant of 9.6 ms, respectively at room temperature.}