A wideband monolithic submillimeter-wave quasi-optical power meter

A novel monolithic power meter has been developed for submillimeter-wave applications (100 GHz to 10 THz). The detector is a 4-mm*4-mm bismuth bolometer integrated on a 1.2- mu m-thick dielectric membrane. This approach results in a wideband high-responsivity detector. The power meter is simple to fabricate, inexpensive, and can be easily calibrated using a low-frequency network. Quasi-optical measurements at 185 GHz show that the bolometer is polarization independent, acts as a Lambertian surface, and could be modeled by a simple transmission line model. The measured low-frequency responsivity for a 70- Omega bolometer, at a bias of 1 V and a video modulation of 300 Hz, is around 1 V/W. The NEP of the detector is around 3 nWHz/sup -1/2/. Potential application areas are antenna coupling efficiency measurements and absolute power measurements at submillimeter wavelengths.<>