RF characterization of cold-electron bolometer integrated with a unilateral finline

Paper in proceeding, 2012

The Cold-Electron Bolometer (CEB) is a very sensitive millimetre-wave detector with high saturation power, fast response and is easy to integrate with planar circuits. We have designed, fabricated and tested CEB detectors integrated across the slot of a unilateral finline on silicon substrate. Bolometers were fabricated using e-beam direct-write trilayer technology. The CEB performance was tested in a He3 sorption cryostat HELIOX-AC-V at a bath temperature of 310 mK. DC IV curves were measured in a current bias mode and optical response was measured by irradiating samples with signals from a black body source mounted inside the cryostat. The finline chip with CEB device was mounted in a waveguide block and connected to the readout system by bond-wires. The RF signal was focused onto the waveguide input using a horn. The signal response was obtained by comparing different IV curves in current-biased mode at different temperatures of the RF source. The response measured as a voltage difference between the IV curves taken at the source temperatures of 5 K and 20 K was about 155 μV.