| 1. |
- Jaramillo-Fernandez, Juliana, et al.
(författare)
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Thermal conductivity of polycrystalline aluminum nitride films : Effects of the microstructure, interfacial thermal resistance and local oxidation
- 2015
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Ingår i: THERMINIC 2015 - 21st International Workshop on Thermal Investigations of ICs and Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781467397056
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Konferensbidrag (refereegranskat)abstract
- The thermal conductivity of polycrystalline aluminum nitride (AlN) films with inhomogeneous structures is experimentally and theoretically investigated. The influence of the grain morphology and size evolution along the cross plane direction of the films is studied by thickness-dependent 3m measurements on AlN monolayers. For AlN/AlN multilayer samples, the impact of oxygen-related defects localized at the interface between two AlN layers, is also analyzed. When the total thickness of these multilayers is downsized from 1107 nm to 270 nm, their measured effective thermal conductivity reduces by 47%, which is smaller than the corresponding reduction of 58% for monolayers. In multilayers, this decrease is due to the additive contributions of the thermal resistances arising from the AlN and AlN/AlN interfaces. The experimental data are interpreted through an analytical model developed for nanocrystalline films with inhomogeneous structures. It is shown that the size effects on the phonon mean free paths and the intrinsic thermal resistance resulting from the inhomogeneous microstructure predominate as the film thickness increases, whilst the contribution of the interface thermal resistance strengthens when the thickness is scaled down.
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| 2. |
- Wang, X., et al.
(författare)
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Collective structures up to spin ∼ 65h in the N 90 isotones 158Er and 157Ho
- 2012
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 381:1
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Tidskriftsartikel (refereegranskat)abstract
- A new collective band with high dynamic moment of inertia in 158Er at spins beyond band termination has been found in addition to the two previously reported ones. The measured transition quadrupole moments (Qt) of these three bands are very similar. These three bands have been suggested to possess a triaxial strongly deformed shape, based on comparisons with calculations using the cranked Nilsson-Strutinsky model and with tilted axis cranking calculations using the Skyrme-Hartree-Fock model. In addition, three collective bands with similar high dynamic moments of inertia, tentatively assigned to 157Ho, have been observed. Thus, it is suggested that all these structures share a common underlying character and that they are most likely associated with triaxial strongly deformed minima which are predicted to be close to the yrast line at spin 50 - 70h.
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