Engineering the thermal conductivity along an individual silicon nanowire by selective helium ion irradiation

Abstract

The ability to engineer the thermal conductivity of materials allows us to control the flow of heat and derive novel functionalities such as thermal rectification, thermal switching, and thermal cloaking. While this could be achieved by making use of composites and metamaterials at bulk scales, engineering the thermal conductivity at micro- and nano-scale dimensions is considerably more challenging. In this work we show that the local thermal conductivity along a single Si nanowire can be tuned to a desired value (between crystalline and amorphous limits) with high spatial resolution through selective helium ion irradiation with a well-controlled dose. The underlying mechanism is understood through molecular dynamics simulations and quantitative phonon-defect scattering rate analysis, where the behavior of thermal conductivity with dose is attributed to the accumulation and agglomeration of scattering centers at lower doses. Beyond a threshold dose, a crystalline-amorphous transition was observed.

References in corpus (4)

• Experiments on transformation thermodynamics: Molding the flow of heat
• Calculation of nanowire thermal conductivity using complete phonon dispersion relations
• Extreme Low Thermal Conductivity in Nanoscale 3D Si Phononic Crystal with Spherical Pores
• A Universal Gauge for Thermal Conductivity of Silicon Nanowires With Different Cross Sectional Geometries

Cited by in corpus (5)

• Transforming heat transfer with thermal metamaterials and devices
• Phonon Coherence and Its Effect on Thermal Conductivity of Nanostructures
• A first-principles study on the lattice thermal conductivity of irradiated glassy states of the Ge${}_2$Sb${}_2$Te${}_5$ phase-change memory material
• Temperature-dependent thermal conductivity of a single Germanium nanowire measured by Optothermal Raman Spectroscopy
• A review of simulation, measurement techniques, and development in chip thermal design