We report measured Tc of superconducting Ti/Au bilayer strips with a width W varying from 5 to 50 µm. The strips were fabricated based on a Ti/Au bilayer that consists of a 41-nm-thick Ti layer to which a 280-nm-thick Au layer was added. We find that the Tc drops as W decreases and the declining trend almost perfectly follows Tc/[mK ] =-738.4 [μm ] 2/W2+91.0 , where Tc(W =∞ ) of 91 mK is consistent with the intrinsic Tc of the bilayer. The result is interpreted as a consequence of the lateral inverse proximity effect originated in normal-metal microstructures, namely Au overhangs that exist at the edges of the Ti/Au bilayer. The Tc shift from the intrinsic Tc should be anticipated in addition to the longitudinal proximity effect from superconducting Nb leads when one designs Ti/Au TESs.
