InP/InGaAs Schottky Barrier Diodes (SBDs) detectors, due to their high electron mobility and low barrier material characteristics, have a very high voltage response sensitivity and are widely used in highly sensitive terahertz wave detection technology. To further reduce device parasitic effects and enhance its high-frequency performance, a novel structure of substrate-free single-mesa T-junction Schottky device is proposed, with a cutoff frequency of 9.5 THz. Based on the novel structure of InP/InGaAs Schottky device technology, terahertz detector modules for multiple frequency bands such as 220~330 GHz, 30~500 GHz, 400~600 GHz, and 500~750 GHz have been developed. Compared with the detectors of the same frequency band from VDI Company in the United States, the detection sensitivity and other indicators are similar, indicating that the device has a promising application prospect in terahertz security imaging.