📝 SummarXiv

Abstract

Amorphous thin film superconductors are promising alternatives for the development of superconducting radiation detectors, especially superconducting nanowire single photon detectors (SNSPDs) and superconducting microwire single photon detectors (SWSPDs), due to their homogeneous nature, ease of deposition, and superconducting parameters comparable to the materials currently being used. A study on the optimization of the growth technology and superconducting transition temperature (TC) of MoSi thin films grown on SiO2 coated Si substrate is reported here. These films have been synthesized by co sputtering of Mo and Si targets with varying compositions and thicknesses to achieve optimized TC values close to that of the bulk. Mo80Si20 and Mo83Si17 compositions of the film, each with a thickness of 17 nm, exhibited the highest TC of 6.4 K and 5.9 K, respectively. Additionally, a meander structure with a 17 um wire width was patterned to estimate the transport critical current density (JC), which was measured to be 1.4E9 A per m2 at 4 K. Variation of the TC with film thickness and deposition pressure has been studied. Electrical resistance as a function of temperature of the film before and after meandering was also studied. These properties are compatible with the fabrication of superconducting nanowire, microwire and wide strip single photon detectors.