Effect of substrate temperature on the growth of Nb3Sn film on Nb by multilayer sputtering

Fabrication of superconducting Nb3Sn film by Co-sputtering

“…The present study of co-sputtering was conducted on the same sputter coater used to grow Nb3Sn films from a single stoichiometric target by growth of Nb/Sn multilayers followed by their interdifusion and reaction at high temperatures to form Nb3Sn [6][7][8][9][10]. The best Nb3Sn films produced from a a stoichiometric target, multilayers, and co-sputtering had Tc = 17.83, 17.84, and 17.61 K, ΔTc = 0.03, 0.03, and 0.19 K, and RRR = 5.41, 4.40, and 3.63, respectively.…”

“…The sputter coater and furnace used in the present study are the same that were used in previous studies of growth of Nb3Sn on Nb and sapphire with a stoichiometric target and multilayer deposition of Nb and Sn [7][8][9][10]. For the different Nb3Sn sputter deposition methods (stoichiometric target, multilayers, and co-sputtering), the base vacuum conditions were similar and the purity of the target materials and Ar sputter gas were also similar.…”

“…Due to the close thermal expansion coefficient of Nb3Sn and Nb, the thermal stress on the Nb3Sn films fabricated on Nb substrates is low [5]. Therefore, there has been significant interest in the growth of Nb3Sn on Nb and the study of the Nb3Sn superconducting and microstructural properties [2][3][4][6][7][8][9][10][11]. Apart from the A15 Nb3Sn, Nb-Sn has other two phases; Nb6Sn5 with Tc < 2.8 K and NbSn2 with Tc < 2.68 K [12].…”

“…We have studied the deposition of Nb3Sn on Nb by sputtering from a single stoichiometric target and depositing multilayers on Nb and Sn followed by reacting them at high temperature [7][8][9][10]. The highest Tc of the films deposited from the stoichiometric target and multilayer sputtering was 17.44 with ΔTc = 0.03 K and 17.93 K with ΔTc = 0.03 K. The corresponding root-mean-square (RMS) surface roughness was 30 and 34 nm for the film deposited from the stoichiometric target and by multilayers, respectively.…”

A combination of angle insensitive stopband/passband filters based on one-dimensional hyperbolic metamaterial quasiperiodic photonic crystals

“…By multilayer sequential sparking on niobium at substrate temperatures ranging from room temperature to 250 °C, Md Nizam Sayeed et al actually described the fabrication of niobium tin (Nb 3 Sn) films. 102 They examined the resistivity of the superconducting films from room temperature to below the superconducting critical temperature T c . The multilayers were deposited at room temperature, yielding a film T c of 17.76 K. The films T c of 17.58 K are produced when the deposition temperature is increased to 250 °C, and voids were significantly reduced.…”