Fabrication and transport characterization of a primary thermometer formed by Coulomb islands in a suspended silicon nanowire

We realized bolometers in suspended highly n-doped silicon nanowires with lateral dimensions down to about 40 nm. Random dopant fluctuations in the suspended wires lead to the formation of multiple tunnel junctions, utilized for Coulomb blockade thermometry. In the low bias regime, we observe relaxation via discrete acoustic phonon modes to give a lower bound for the sensitivity.