Detection of terahertz radiation using submicron field effect transistors and their use for inspection applications

We investigated room temperature detection of terahertz radiation by using two different types of transistors (Strained Silicon Modulation field effect transistor, GaAs PHEMT). Experimental results show a good level of response under excitation at 0.3 THz. Competitive performance parameters were obtained (NEP and responsivity) in comparison with other detectors. Enhancement of the photoresponse signal by imposing a dc drain-to-source current (I_ds) was observed experimentally. Inspection of hidden objects by using those devices within a terahertz imaging setup was demonstrated at 300 GHz and a better image was obtained under I_ds.