PT Journal
AU Ryabchun, SA
   Tretyakov, IV
   Pentin, IV
   Kaurova, NS
   Seleznev, VA
   Voronov, BM
   Finkel, MI
   Maslennikov, SN
   Gol'tsman, GN
TI Low-noise wide-band hot-electron bolometer mixer based on an NbN film
SO Radiophys. Quant. Electron.
PY 2009
BP 576
EP 582
VL 52
IS 8
DI 10.1007/s11141-010-9162-7
DE HEB mixer; in-situ contacts; noise temperature; conversion gain bandwidth; diffusion cooling channel
AB We develop and study a hot-electron bolometer mixer made of a two-layer NbN–Au film in situ deposited on a silicon substrate. The double-sideband noise temperature of the mixer is 750 K at a frequency of 2.5 THz. The conversion efficiency measurements show that at the superconducting transition temperature, the intermediate-frequency bandwidth amounts to about 6.5 GHz for a mixer 0.112 μm long. These record-breaking characteristics are attributed to the improved contacts between a sensitive element and a helical antenna and are reached due to using the in situ deposition of NbN and Au layers at certain stages of the process.
ER