Reduction of noise equivalent power in Terahertz detector based on InP double heterojunction bipolar transistor by biasing the collector

This paper presents the low frequency noise and the photoresponse in InP double heterojunction bipolar transistor (DHBT) THz detectors. The current responsivity of 0.23 A/W and a noise equivalent power of 3x10-10 W/Hz1/2 have been measured at 1 kHz modulation frequency. We found that the collector bias application reduced the noise equivalent power at least 4.5 times.