The upper critical field of rf‐sputtered WNx and MoNx films

The upper critical field and other electronic properties, such as resistivity, temperature coefficient of resistance, and the Hall constant of rf‐sputtered WNx and MoNx films were measured. It was observed that the upper critical field is independent of the nitrogen partial pressure, whereas the resistivity is strongly affected. The structure and diffraction patterns of these films were also investigated by transmission electron microscopy (TEM). Our measured results are interpreted in terms of the influence of microscopic regions, which affect differently the normal and superconducting properties, as is found for NbNx films.

[1]  G. Bergmann.  The upper critical field of quenched condensed Sn, Tl, In and Hg with extremely short mean free path , 1974 .

[2]  O. Fischer,et al.  Some superconducting and normal state properties of niobium nitride thin films , 1974 .

[3]  P. Petroff,et al.  Resistivity behavior and phase transformations in β-W thin films , 1974 .

[4]  D. Ast,et al.  Electronmicroscopic evidence for a columnar‐void‐type structure in sputtered NbN films , 1974 .

[5]  K. Reichelt,et al.  Superconductivity transition temperatures of rf reactively sputtered NbN Films , 1973 .

[6]  P. Schmidt.  Superconductivity of transition metal thin films deposited by noble gas ion beam sputtering , 1973 .

[7]  G. Bergmann.  Upper Critical Field and the Density of States in Amorphous Strong-Coupling Superconductors , 1973 .

[8]  R. Hammond,et al.  SUPERCONDUCTIVITY IN AMORPHOUS TRANSITION-METAL ALLOY FILMS. , 1973 .

[9]  T. Yamashita,et al.  Upper critical field of superconducting NbN films , 1972 .

[10]  M. Strongin,et al.  The superconducting transition temperatures of disordered Nb, W, and Mo films , 1969 .

[11]  G. W. Hull,et al.  Superconductivity of niobium thin films deposited by dc-diode sputtering , 1967 .

[12]  K. Chopra,et al.  Face-centred cubic modification in sputtered films of tantalum, molybdenum, tungsten, rhenium, hafnium and zirconium , 1967 .

[13]  A. S. Cooper,et al.  SUPERCONDUCTIVITY IN FILMS OF BETA TUNGSTEN AND OTHER TRANSITION METALS , 1965 .

[14]  M. Strongin,et al.  Superconductivity in tungsten films , 1965 .

[15]  A. J. Hegedüs,et al.  Über die Bildungsbedingungen und Eigenschaften des β‐Wolframs. Weiterer Beitrag zur Reduktion des Wolframtrioxyds , 1957 .

[16]  A. Sieverts,et al.  Molybdän und Stickstoff , 1936 .