A novel room-temperature microbolometer array chip consisting of an Nb5N6 thin film microbridge and a dipole planar antenna, which is used as a terahertz （THz） detector, is described in this paper. Due to the high-t...A novel room-temperature microbolometer array chip consisting of an Nb5N6 thin film microbridge and a dipole planar antenna, which is used as a terahertz （THz） detector, is described in this paper. Due to the high-temperature coefficient of the resistance of the Nb5N6 thin film, which is as high as –0.7% K-1 , such an antenna-coupled microbolometer is ideal for detecting signals in a frequency range from 0.22THz to 0.33THz. The dc responsivity, calculated from the measured I–V curve of the Nb5N6 microbolometer, is about –760 V/W at a bias current of 0.19mA. A typical noise voltage as low as 10 nV/Hz 1/2 yields a low noise equivalent power （NEP） of 1.3×10-11W/Hz 1/2 at a modulation frequency above 4kHz, and the best RF responsivity, characterized using an infrared device measuring method, is about 580V/W, with the corresponding NEP being 1.7×10-11W/Hz 1/2 . In order to further test the performance of the Nb5N6 microbolometer, we construct a quasi-optical type receiver by attaching it to a hyperhemispherical silicon lens, and the result is that the best responsivity of the receiver is up to 320V/W. This work could offer another way to develop a large scale focal-plane array in silicon using simple techniques and at low cost.展开更多
Voltage responsivity of bolometer will benefit from high temperature coefficient of resistance (TCR) of the material. The Nb5N6 thin solid films we proposed in this paper have high TCR, compared with the commonly-used...Voltage responsivity of bolometer will benefit from high temperature coefficient of resistance (TCR) of the material. The Nb5N6 thin solid films we proposed in this paper have high TCR, compared with the commonly-used materials such as Nb and Bi. The films were sputtered on Si(100), SiO2/Si(100), SiO2 substrates by using radio frequency (rf) magnetron sputtering. The deposition conditions have been optimized to get high TCR. The highest TCR is over 0.91% K-1 at 300 K and up to 4.5% K -1―7% K-1 at 78 K, which is good enough to be used in terahertz detection and thermometer fabrication in the range from 78 K to 300 K.展开更多
基金Project supported by the National Basic Research Program of China (Grant No. 2011CBA00107)the National High-Technology Research Development Program of China (Grant No. 2011AA010204)
文摘A novel room-temperature microbolometer array chip consisting of an Nb5N6 thin film microbridge and a dipole planar antenna, which is used as a terahertz （THz） detector, is described in this paper. Due to the high-temperature coefficient of the resistance of the Nb5N6 thin film, which is as high as –0.7% K-1 , such an antenna-coupled microbolometer is ideal for detecting signals in a frequency range from 0.22THz to 0.33THz. The dc responsivity, calculated from the measured I–V curve of the Nb5N6 microbolometer, is about –760 V/W at a bias current of 0.19mA. A typical noise voltage as low as 10 nV/Hz 1/2 yields a low noise equivalent power （NEP） of 1.3×10-11W/Hz 1/2 at a modulation frequency above 4kHz, and the best RF responsivity, characterized using an infrared device measuring method, is about 580V/W, with the corresponding NEP being 1.7×10-11W/Hz 1/2 . In order to further test the performance of the Nb5N6 microbolometer, we construct a quasi-optical type receiver by attaching it to a hyperhemispherical silicon lens, and the result is that the best responsivity of the receiver is up to 320V/W. This work could offer another way to develop a large scale focal-plane array in silicon using simple techniques and at low cost.
基金Supported by the National Basic Research Programme of China (Grant Nos. 2006CB601006 and 2007CB310404)National High-Tech R&D Programme of China (Grant No. 2006AA12Z120)National Natural Science Foundation of China (NSFC) (Grant Nos. 10778602 and 60721063)
文摘Voltage responsivity of bolometer will benefit from high temperature coefficient of resistance (TCR) of the material. The Nb5N6 thin solid films we proposed in this paper have high TCR, compared with the commonly-used materials such as Nb and Bi. The films were sputtered on Si(100), SiO2/Si(100), SiO2 substrates by using radio frequency (rf) magnetron sputtering. The deposition conditions have been optimized to get high TCR. The highest TCR is over 0.91% K-1 at 300 K and up to 4.5% K -1―7% K-1 at 78 K, which is good enough to be used in terahertz detection and thermometer fabrication in the range from 78 K to 300 K.
