Design and Characterisation of Titanium Nitride Subarrays of Kinetic Inductance Detectors for Passive Terahertz Imaging

摘要

We report on the investigation of titanium nitride (TiN) thin films deposited via atomic layer deposition (ALD) for microwave kinetic inductance detectors (MKID). Using our in-house ALD process, we have grown a sequence of TiN thin films (thickness 15, 30, 60?nm). The films have been characterised in terms of superconducting transition temperature $$T_mathrm{c}$$ T c , sheet resistance $$R_mathrm{s}$$ R s and microstructure. We have fabricated test resonator structures and characterised them at a temperature of 300?mK. At 350 GHz, we report an optical noise equivalent power $$hbox {NEP}_mathrm{opt} pprox 2.3imes 10^{-15}~hbox {W}/sqrt{hbox {Hz}}$$ NEP opt ≈ 2.3 × 10 - 15 W / Hz , which is promising for passive terahertz imaging applications.