Growth of single-crystal TiN/VN strained-layer superlattices with extremely high mechanical hardness
-
- U. Helmersson
- Department of Physics, Linköping University, S-581 83 Linköping, Sweden
-
- S. Todorova
- Department of Physics, Linköping University, S-581 83 Linköping, Sweden
-
- S. A. Barnett
- Department of Physics, Linköping University, S-581 83 Linköping, Sweden
-
- J.-E. Sundgren
- Department of Physics, Linköping University, S-581 83 Linköping, Sweden
-
- L. C. Markert
- Department of Materials Science, the Coordinated Science Laboratory, and the Materials Research Laboratory, University of Illinois, 1101 West Springfield Avenue, Urbana, Illinois 61801
-
- J. E. Greene
- Department of Materials Science, the Coordinated Science Laboratory, and the Materials Research Laboratory, University of Illinois, 1101 West Springfield Avenue, Urbana, Illinois 61801
抄録
<jats:p>Single-crystal TiN/VN strained-layer superlattices (SLS’s) with layer thicknesses lTiN =lVN =λ/2 (where λ is the period of the superlattice) ranging from 0.75 to 16 nm have been grown on MgO(100 ) substrates by reactive magnetron sputtering. Cross-sectional transmission electron microscopy (TEM) and x-ray diffraction examinations showed that the films were single crystals exhibiting coherent interfaces and several orders of superlattice reflections. There was no evidence in either plan-view or cross-sectional TEM analyses of misfit interfacial dislocation arrays. The primary defects observed were dislocation loops with a diameter of 8–10 nm extending through several layers and small defects with a diameter of 1–2 nm that were confined within single layers. Microindentation hardness values H, measured as a function of λ in films with a total thickness of 2.5 μm, increased from 2035±280 kg mm−2 for Ti0.5V0.5N alloys (i.e., λ=0) to reach a maximum of 5560±1000 kg mm−2 at λ=5.2 nm and then decreased rapidly to 3950±550 kg mm−2 at λ=7.5 nm. Further increases in λ resulted in a slower decrease in H to 3640±550 kg mm−2 at λ=32 nm. The large error bars in the H values for the SLS samples were due to the difficulty in measuring such extremely high hardnesses in thin films. (H for pure single-crystal TiN and VN films were 2200±300 and 1620±200 kg mm−2, respectively.) SLS samples grown with constant λ=6.5 nm, but different lTiN /λ ratios, exhibited a maximum hardness at lTiN /λ≂0.3.</jats:p>
収録刊行物
-
- Journal of Applied Physics
-
Journal of Applied Physics 62 (2), 481-484, 1987-07-15
AIP Publishing
- Tweet
詳細情報 詳細情報について
-
- CRID
- 1363388844995868160
-
- NII論文ID
- 30015830059
-
- DOI
- 10.1063/1.339770
-
- ISSN
- 10897550
- 00218979
-
- データソース種別
-
- Crossref
- CiNii Articles