Suspended Antenna-Coupled Nanothermocouple Array for Long-Wave Infrared Detection

We study the thermal response of arrays of suspended antenna-coupled nanothermocouple (ACNTC) in response to long-wave infrared radiation. ACNTCs in the array are suspended over air-filled cavities formed in the Si substrate by XeF2 vapor etching. The cavities thermally insulate the devices from the substrate. In addition, well-designed cavities reflect the incident IR radiation and create constructive interference, thus increasing the thermal response by about 100 fold compared to previously reported devices on a substrate. Polarization-dependent measurements are presented for antenna arrays consisting of 200 devices, and we show antenna-array-size-dependent response when various numbers of ACNTCs are connected in series.