CMOS-compatible 8 × 2 thermopile array

A front-cut infrared thermopile array with good CMOS compatibility is demonstrated in this paper. Properly arranged narrow windows in IR absorbing area of the thermopile are designed along the [1 0 0] direction on the (1 0 0) Si wafer. Our experiment shows that this infrared thermopile array has good responsivity of 43 v/w, detectivity of 2.8 × 107 cm Hz1/2/W, and response time of 9 ms as well as good yield better than 90%. A single element reached 99% yield in a wafer. The responsivity non-uniformity of elements in a 8 × 2 thermopile array does not exceed 3% and it costs only 90 etching min for the element size of 490 μm × 490 μm. Based on this thermopile array, an IR imager is developed.