The growth, structure, and mechanical properties of TiN/V[sub x]Nb[sub 1[minus]x]N superlattice thin films

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1993

OSTI ID:7236497

Mirkarimi, P B

The growth, structure, and mechanical properties of epitaxial TiN/V[sub x]Nb[sub 1[minus]x]N superlattice thin films was investigated. An ultra-high vacuum, magnetron sputtering system was designed and constructed for the deposition and in-situ LEED/AES analysis of nitride superlattice films. The system was characterized to determine the conditions under which epitaxial, stoichiometric TiN, VN, and NbN films could be deposited on MgO(100) substrates at T [approximately] 700[degrees]C. Epitaxial TiN/V[sub x]Nb[sub 1[minus]x]N superlattices were deposited on MgO(100) substrates, where the lattice-mismatch ([delta]) was [approximately] 0.3% for x = 0.6 and [delta] [approximately] 1.7% for x = 0.3. The former [delta] value allowed for a determination of the mechanical properties for an almost strain-free superlattice. The latter value of [delta] [approximately] 1.7% introduces a significant amount of strain into the superlattice, yet it is lower than that of previously studied TiN/VN and TiN/NbN superlattices; this increases the [lambda] range over which coherency strains are present. Structural analysis of the superlattices through techniques such as XRD, XTEM, and LEED shows that the superlattices are epitaxial and that a strong composition modulation is present. Two to ten orders of superlattice satellite reflections were observed, depending on [lambda]. The maximum hardness enhancement (H[sub max]) was [approximately] 75% for the x = 0.3 superlattices, while it was [approximately] 50% for the almost lattice-matched x = 0.6 superlattices. The difference in H[sub max] between the two systems can be attributed to differences in coherency strains. Extensive elastic property measurements show that there are no elastic anomalies in the [lambda] region in which the hardness enhancements are observed.

• Research Organization: Northwestern Univ., Chicago, IL (United States)
• OSTI ID: 7236497
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360203 -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALLOYS
ELASTICITY
HARDNESS
INTERMETALLIC COMPOUNDS
MECHANICAL PROPERTIES
MICROSTRUCTURE
NIOBIUM COMPOUNDS
NIOBIUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
REFRACTORY METAL COMPOUNDS
SPUTTERING
SUPERLATTICES
TENSILE PROPERTIES
TITANIUM COMPOUNDS
TITANIUM NITRIDES
TRANSITION ELEMENT COMPOUNDS
VANADIUM COMPOUNDS
VANADIUM NITRIDES