A waveguide-coupled millimetre-wave TES bolometer suitable for 2-D arrays

We are developing a single-pixel antenna-coupled bolometric detector for use in low-background millimetre-wave astronomy. The device consists of a radial probe in a rectangular waveguide coupled to a Ti/Au transition edge sensor (TES). The signal propagates from the antenna along a superconducting microstrip line into a metal resistor on a thermally isolated Si3N4 island, where the TES is also located. We have designed and built prototype pixels optimised for 150 GHz band measurements. We discuss our progress in the development as well as the first results from dark measurements. PAC