High T/sub c/ superconducting B1 phase MoN films prepared by low-energy ion-assisted deposition
Metastable B1 phase MoN was synthesized by low-energy ion-assisted thin-film growth techniques at deposition temperatures T/sub D/ = 400, 500, and 700/sup 0/C. The films were condensed under the action of mixed Ar/sup +/ and N/sub 2//sup +/ ion species at an ion to condensing atom arrival rate ratio of 1.0. For each deposition temperature, films were prepared at various ion energies in the range 2--200 eV. The presence of chemically reactive N/sub 2//sup +/ ions and the use of low ion energies allow both structural and chemical selectivity, facilitate increased incorporation of nitrogen, and promote ordering of the defect structure of cubic MoN. The films were characterized by x-ray diffraction, by measurements of superconducting temperature T/sub c/ and by temperature-dependent resistivity rho(T). Collectively the film properties strongly depend on ion energy and deposition temperature. The composition, lattice parameter, crystalline preferred orientation, and grain size can be controlled by varying ion energy. The resistivity shows an anomalous temperature dependence that is typical of disordered metals, i.e., electron localization governs electrical conduction with the temperature coefficient of resistivity changing sign according to the Mooij correlation. At optimum deposition conditions the resistivity is metallike (phonon contribution rho/sub thermal/ >0), T/sub c/ = 6.2 K, the resistivity ratio RR = 1.1, and rho/sub 300//sub //sub K/ = 120 ..mu cap omega.. cm. Annealing of films at 700/sup 0/C causes an improvement in properties with T/sub c/approx. =12 K, RR = 1.7, and rho/sub thermal/ = 60--80 ..mu cap omega.. cm.
- Research Organization:
- CSIRO Division of Applied Physics, Sidney, Australia 2070
- OSTI ID:
- 6511549
- Journal Information:
- J. Appl. Phys.; (United States), Vol. 62:2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of preparation conditions and low-temperature ion irradiation on superconductivity and electrical resistivity of amorphous (Mo/sub 0. 6/Ru/sub 0. 4/)/sub 1-x/B/sub x/ films
Optical and electrical properties of ion-beam-irradiated films of organic molecular solids and polymers
Related Subjects
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
MOLYBDENUM NITRIDES
CRYSTAL STRUCTURE
DEPOSITION
SUPERCONDUCTIVITY
TRANSITION TEMPERATURE
ANNEALING
ARGON IONS
EXPERIMENTAL DATA
ION BEAMS
NITROGEN IONS
SYNTHESIS
THIN FILMS
BEAMS
CHARGED PARTICLES
DATA
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
FILMS
HEAT TREATMENTS
INFORMATION
IONS
MOLYBDENUM COMPOUNDS
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
PHYSICAL PROPERTIES
PNICTIDES
REFRACTORY METAL COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties
656100 - Condensed Matter Physics- Superconductivity
360201 - Ceramics
Cermets
& Refractories- Preparation & Fabrication