Title :
Antenna-coupled microbolometer array for terahertz detection
Author :
Tu, X.C. ; Kang, L. ; Liu, X.H. ; Mao, Q.K. ; Wan, C. ; Chen, J. ; Jin, B.B. ; Ji, Z.M. ; Xu, W.W. ; Wu, P.H.
Author_Institution :
Sch. of Electron. Sci. & Eng., Nanjing Univ., Nanjing, China
Abstract :
A novel room-temperature microbolometer for terahertz wave is described in this paper. Each microbolometer in the array consists of a Nb5N6 thin film microbridge and a dipole planar antenna. Such antenna-coupled microbolometer behaves very well for detecting signals from 0.2 THz to 0.32 THz, thanks to the fact that the temperature coefficient of resistance of the Nb5N6 thin film is as high as -0.7% K-1. The DC responsivity, calculated from the measured I-V curve, of the microbolometer is about 730 V/W at the bias current of 0.4 mA. A typically noise voltage as low as 10 nV/√Hz lead to a low noise equivalent power (NEP) of 1.5 × 10-11 W/√Hz for modulation frequencies above 4 kHz. The RF responsivity and corresponding NEP are experimentally shown to be 550 V/W and 2 × 10-11 W/√Hz, respectively, at 4 kHz for 0.27 THz detecting.
Keywords :
bolometers; dipole antenna arrays; microsensors; planar antenna arrays; superconducting arrays; superconducting photodetectors; superconducting thin films; terahertz wave detectors; thin film sensors; type II superconductors; DC responsivity; NEP; RF responsivity; antenna coupled microbolometer array; current 0.4 mA; dipole planar antenna; frequency 0.2 THz to 0.32 THz; frequency 4 kHz; noise equivalent power; signal detection; temperature coefficient of resistance; terahertz wave detection; thin film microbridge; Antennas; Educational institutions; Q measurement; Silicon;
Conference_Titel :
Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2012 37th International Conference on
Conference_Location :
Wollongong, NSW
Print_ISBN :
978-1-4673-1598-2
Electronic_ISBN :
2162-2027
DOI :
10.1109/IRMMW-THz.2012.6380449