Oral Presentation

Fabrication of 2 THz Waveguide Type Hot Electron Bolometer Mixer

Author(s): Akira KAWAKAMI(NICT), Yoshihisa IRIMAJIRI(NICT), Ming-Jye WANG(ASIAA), Wei-Chun Lu(ASIAA), Yuji HISHIDA(NICT), Hirotaka TERAI(NICT)

Presenter: Akira Kawakami (NICT)

We have been developing a 2 THz-band waveguide-type hot electron bolometer mixer (HEBM) for global environment measurement, information communication, etc. For HEBM, Ni-HEBM structure that uses nickel to leave superconductivity only between the metal electrodes was used, and the NbN strip lengths of 0.1 μm and 0.2 μm were prepared. The HEBMs were constructed on a Si3N4 membrane bridge. The bridge size is 55 μm-wide, 820 μm-long, and 1 μm-thick, respectively, and it is supported by a Si frame with a size of 3 mm by 3 mm and a thickness of 200 μm. To construct the frame structure, we investigated Si deep reactive ion etching using MgO thin film as an inorganic resist and confirmed that a 200-μm-thick Si substrate can be etched by using a 10-nm-thick MgO resist. The fabricated mixer was installed in a waveguide-type mixer mount with a WR-0.51 waveguide and a diagonal horn. The measured receiver noise temperature was about 1,690 K (DSB).