Electron-phonon coupling and thermal conductance at a metal-semiconductor interface: First-principles analysis

Journal Article · Tue Apr 07 00:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4916729· OSTI ID:22399399

Sadasivam, Sridhar; Waghmare, Umesh V. ^[1]

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1. Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064 (India)

The mechanism of heat transfer and the contribution of electron-phonon coupling to thermal conductance of a metal-semiconductor interface remains unclear in the present literature. We report ab initio simulations of a technologically important titanium silicide (metal)–silicon (semiconductor) interface to estimate the Schottky barrier height, and the strength of electron-phonon and phonon-phonon heat transfer across the interface. The electron and phonon dispersion relations of TiSi{sub 2} with C49 structure and the TiSi{sub 2}-Si interface are obtained using first-principles calculations within the density functional theory framework. These are used to estimate electron-phonon linewidths and the associated Eliashberg function that quantifies coupling. We show that the coupling strength of electrons with interfacial phonon modes is of the same order of magnitude as coupling of electrons to phonon modes in the bulk metal, and its contribution to electron-phonon interfacial conductance is comparable to the harmonic phonon-phonon conductance across the interface.

• OSTI ID: 22399399
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 13; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
DENSITY FUNCTIONAL METHOD
DIFFUSION BARRIERS
DISPERSION RELATIONS
ELECTRON-PHONON COUPLING
ELECTRONS
HEAT TRANSFER
INTERFACES
LINE WIDTHS
PHONONS
SEMICONDUCTOR MATERIALS
SILICON
THERMAL CONDUCTIVITY
TITANIUM SILICIDES