Antenna-coupled transition-edge hot-electron microbolometers

Shafinaz Ali, Peter T. Timbie, Siddharth Malu, Dan McCammon, Kari L. Nelms, Rashmi Pathak, Daniel W. van der Weide, Christine A. Allen, J. Abrahams, James A. Chervenak, Wen-Ting Hsieh, Timothy M. Miller (+6 others)
2004 Millimeter and Submillimeter Detectors for Astronomy II  
We are developing a new type of detector for observational cosmology and astrophysical research. Incoming radiation from the sky is coupled to a superconducting microstrip transmission line that terminates in a thin film absorber. At sub-Kelvin temperature, the thermal isolation between the electrons and the lattice makes it possible for the electrons in the small absorber (100's of µm 3 ) and superconducting bilayer (Transition Edge Sensor) to heat up by the radiation absorbed by the electrons
more » ... of the normal absorbing layer. We call this detector a Transition-edge Hot-electron Micro-bolometer (THM). THMs can be fabricated by photo lithography, so it is relatively easy to make matched detectors for a large focal plane array telescope. We report on the thermal properties of Mo/Au THMs with Bi/Au absorbers. TRANSITION-EDGE HOT-ELECTRON MICROBOLOMETER TES devices have proved to be a lot faster than the conventional Neutron-Transmutation-Doped (NTD) or doped Si bolometers. TES bolometers are a close match for the NTD bolometers in sensitivity. In addition TES bolometers can be fabricated lithographically and multiplexed making them highly suitable for large array formats. We are building a type of TES bolometer we call Transition-edge Hot-Electron Microbolometer (THM). A small TES is in thermal contact with a normal metal absorber. The electrons in the normal metal absorber are heated by incident radiation. The weak electron-phonon thermal coupling in metals at low temperature allows the the temperature of the electrons in the adjacent TES to rise for a small change in absorbed power. The thermally active area for the antenna coupled bolometer can be much smaller than the wavelength of
doi:10.1117/12.552836 fatcat:fbo5wc37l5fvfmrsstganpmp64