Suppressed Critical Current in Superconducting Nanowire Single-Photon Detectors With High Fill-Factors
Joel K. W. Yang, Andrew J. Kerman, Eric A. Dauler, Bryan M. Cord, Vikas Anant, R. J. Molnar, Karl K. Berggren · IEEE Transactions on Applied Superconductivity · 2009
In this work we present a new fabrication process that enabled the fabrication of superconducting nanowire single photon detectors SNSPD with fill-factors as high as 88% with gaps between nanowires as small as 12 nm. This fabrication process combined high-resolution electron-beam lithography with photolithography. Although this work was motivated by the potential of increased detection efficiency with higher fill-factor devices, test results showed an unexpected systematic suppression in device critical currents with increasing fill-factor.