Flexible PCB Vertical Thermopile IR Sensor

We present the design, fabrication and characterization of vertical thermopile infra-red (IR) sensors. The sensors are produced in batches in a standard flexible printed circuit board (flex PCB) material. The vertical design opens up for large area detection and longer thermopile chains. The sensors consist of series of 88 vertically interconnected thermocouples in a 75 μm thick polyimide foil (Kapton HN
^™
). The sensors showed a voltage response to an IR pulse of 1.2 V/(W/mm
²
).