Interfacial reactions in epitaxial Al/TiN(111) model diffusion barriers: Formation of an impervious self-limited wurtzite-structure AIN(0001) blocking layer

Journal Article · Fri Jun 15 04:00:00 EDT 2001 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1372162· OSTI ID:40204189

Chun, J -S; Desjardins, P; Lavoie, C; Shin, C -S; Cabral, C; Petrov, I; Greene, J E

Single-crystal TiN(111) layers, 45 nm thick, were grown on MgO(111) by ultrahigh vacuum reactive magnetron sputter deposition in pure N{sub 2} discharges at T{sub s}=700{degree}C. Epitaxial Al(111) overlayers, 160 nm thick, were then deposited at T{sub s}=100{degree}C in Ar without breaking vacuum. Interfacial reactions and changes in bilayer microstructure due to annealing at 620 and 650{degree}C were investigated using x-ray diffraction and transmission electron microscopy (TEM). The interfacial regions of samples annealed at 620{degree}C consist of continuous {approx_equal}7-nm-thick epitaxial wurtzite-structure AlN(0001) layers containing a high density of stacking faults, with {approx_equal}22 nm thick tetragonal Al{sub 3}Ti(112) overlayers. Surprisingly, samples annealed at the higher temperature are more stable against Al{sub 3}Ti formation. TEM analyses of bilayers annealed at 650{degree}C (10{degree}C below the Al melting point!) reveal only the self-limited growth of an {approx_equal}3-nm-thick interfacial layer of perfect smooth epitaxial wurtzite-structure AlN(0001) which serves as an extremely effective deterrent for preventing further interlayer reactions. {copyright} 2001 American Institute of Physics.

• Sponsoring Organization: (US)
• OSTI ID: 40204189
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 12 Vol. 89; ISSN 0021-8979
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DEPLETION LAYER
DIFFUSION BARRIERS
STACKING FAULTS
TIN 111
TRANSMISSION ELECTRON MICROSCOPY
ULTRAHIGH VACUUM
X-RAY DIFFRACTION