抄録
A thermoelectric far-infrared sensor with a subwavelength structured (SWS) absorber is presented. The sensor has a low cost potential because it is fabricated with the conventional CMOS manufacturing process and micromachining technology. To increase the responsivity of the sensor, we have developed the SWS absorber that has high infrared absorptivity of more than 80 %. The sensor achieved high responsivity of 3,900 V/W. The sensor has external dimensions of 100 μm × 100 μm. The fabricated SWS absorber has 4 μm pitch and 1.9 μm height. The SWS absorber effectively reduces surface reflection loss over a wide spectral region and enhances the absorptivity. We observed that the sensor with the SWS absorber had 20 % higher responsivity than that with the flat surfaced absorber.