Selective growth of B1-NbN in Nb thin film by high-dose nitrogen molecular ion implantation

Journal Article · Tue Nov 01 04:00:00 EST 1988 · J. Mat. Res.; (United States)

OSTI ID:6749560

Tanabe, N; Iwaki, M

Nitrogen molecular ion implantations have been performed in niobium thin films to form B1-NbN layers with an accelerating voltage of 150 kV up to a dose of 5 x 10/sup 17/ N/sup +//sub 2/ ions/cm/sup 2/ at room temperature. Measurements of superconducting transition temperature (T/sub c/), Auger electron spectroscopy analyses (AES), and x-ray diffraction analyses (XRD) have been carried out as a function of nitrogen dose in order to characterize the implanted layer. It has been found that there are two regions in the dose dependence of T/sub c/; in the low-dose case, T/sub c/ decreases from the initial value of 8 K to less than 4.2 K with increasing dose, and in case of the high dose (more than 2.5 x 10/sup 17/ ions/cm/sup 2/) it increases rapidly to 11 K and becomes independent of the implantation dose. The XRD patterns indicate the generation of lattice disorder at the low dose, the formation of Nb/sub 2/N and epsilonNbN at the intermediate dose, and the formation of deltaNbN (B1 structure) at the high dose; the selective growth of deltaNbN occurs at the highest dose, in spite of the fact that thermodynamically Nb/sub 2/N and epsilonNbN are equilibrium phases at room temperature and they are formed at the intermediate dose. In conclusion, high-dose nitrogen implantation at room temperature causes the formation of deltaNbN to increase T/sub c/.

• Research Organization: Fujikura Ltd., Kiba 1-5-1, Kohtoh-ku, Tokyo 135, Japan
• OSTI ID: 6749560
• Journal Information: J. Mat. Res.; (United States), Journal Name: J. Mat. Res.; (United States) Vol. 3:6; ISSN JMREE
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
AUGER ELECTRON SPECTROSCOPY
BEAMS
CHARGED PARTICLES
CHEMICAL COMPOSITION
COHERENT SCATTERING
CRYSTAL STRUCTURE
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON SPECTROSCOPY
FILMS
ION BEAMS
ION IMPLANTATION
IONS
NIOBIUM COMPOUNDS
NIOBIUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
NITROGEN IONS
PHYSICAL PROPERTIES
PNICTIDES
REFRACTORY METAL COMPOUNDS
SCATTERING
SPECTROSCOPY
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
THIN FILMS
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
X-RAY DIFFRACTION