Calculation of Thermal Resistance of Tapered Silicon Nanowires with Phonon-Boundary Scattering

2016 ◽  
Vol 8 (6) ◽  
pp. 1216-1220
Author(s):  
Sang-Hyeok Cho ◽  
No-Won Park ◽  
Sang-Kwon Lee ◽  
Young-Gui Yoon
Keyword(s):  
Thermal Resistance ◽  
Silicon Nanowires ◽  
Boundary Scattering

The thermal conductivity of solid helium

1952 ◽  
Vol 214 (1119) ◽  
pp. 546-563 ◽  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Resistance ◽  
Single Crystals ◽  
Liquid Helium ◽  
Solid Helium ◽  
Boundary Scattering ◽  
Conductivity Measurements ◽  
Helium Ii ◽  
Characteristic Temperatures ◽  
Thermal Conductivities

The thermal conductivities of crystals of solid helium at densities between 0⋅194 and 0⋅218 g/cm 3 have been measured at liquid-helium temperatures. In order to interpret the results, the specific heat of solid helium at these densities has been measured from 0⋅6 to 1⋅4° K. The range of densities employed is sufficient to allow the observation of Debye characteristic temperatures varying by 40 %, and of thermal conductivities varying by factors of over 10. It is shown that the conductivity measurements are in accord with the ‘umklapp’ type of thermal resistance derived by Peierls (1929, 1935). Further work was restricted by the difficulty of obtaining good single crystals in narrow tubes, but measurements of the conductivity at one density were obtained down to 0⋅3° K. In this region the conductivity is limited by boundary scattering and is higher than that observed by other authors for liquid helium II at similar temperatures.

Enormous suppression of phonon transport in silicon nanowires with five-fold twin boundary

2018 ◽  
Vol 6 (38) ◽  
pp. 18533-18542 ◽  
Author(s):  
Yufei Gao ◽  
Yanguang Zhou ◽  
Ming Hu
Keyword(s):  
Twin Boundary ◽  
Silicon Nanowires ◽  
Phonon Transport ◽  
Boundary Scattering

The five-fold twin boundary not only leads to much more intense boundary scattering, but also results in vibrational hybridization.

Molecular Dynamic Simulations of Contact Thermal Resistance between Two Individual Silicon Nanowires

2011 ◽  
Vol 483 ◽  
pp. 663-667
Author(s):  
Jian Giang Wang ◽  
Ke Dong Bi ◽  
Yun Fei Chen
Keyword(s):  
Thermal Resistance ◽  
Molecular Dynamic ◽  
Silicon Nanowires ◽  
Bonding Strength ◽  
Unit Area ◽  
Van Der Waals ◽  
Molecular Dynamic Simulations ◽  
Contact Thermal Resistance ◽  
Dynamic Simulations ◽  
Reasonable Result

Contact thermal resistance between two individual silicon nanowires is investigated by nonequilibrium molecular dynamic simulations as a function of temperature, overlap, bonding strength and spacing between them. The results indicate that contact thermal resistance per unit area increases with temperature increasing. The increasing overlap leads to the increase of the contact areas, which enhances the per unit area contact thermal resistance. With a weakened interfacial van der Waals bonding strength, the contact thermal resistance per unit area increases significantly. Additionally, a method to verify the effect of the bonding strength is used by changing the interfacial spacing, and a reasonable result is observed.

Impact of Thermal Sub-Continuum Effects on Electrical Performance of Silicon-on-Insulator Transistors

2005 ◽  
Author(s):  
Keivan Etessam-Yazdani ◽  
Rozana Hussin ◽  
Mehdi Asheghi
Keyword(s):  
Thermal Resistance ◽  
Drain Current ◽  
Silicon On Insulator ◽  
Electrical Performance ◽  
Gate Length ◽  
Boundary Scattering ◽  
Self Heating ◽  
Soi Devices ◽  
The Impact ◽  
Channel Region

In this manuscript, the impact of scaling on self-heating of silicon-on-insulator (SOI) transistors is investigated. Effect of temperature dependent phonon-boundary scattering in silicon thin films, which results in reduction in thermal conduction in the channel region, is incorporated into a electro-thermal simulation tool. Results of DC electro-thermal simulations are used to study drain current degradation due to self-heating and to obtain the thermal resistance of SOI devices as a function of gate length and silicon layer thickness. The device thermal resistance is increased by nearly a factor of 3 due to the scaling of gate length from 180nm to 10nm. Self-heating in SOI devices with gate length of 10nm can be responsible for up to 30% reduction in the saturation current and neglecting phonon-boundary scattering in the channel region may underestimate the degradation of drain current due to self-heating by nearly a factor of two.

scholarly journals Thermal resistance of twist boundaries in silicon nanowires by nonequilibrium molecular dynamics

AIP Advances ◽  
2017 ◽  
Vol 7 (4) ◽  
pp. 045105 ◽  
Author(s):  
Jan K. Bohrer ◽  
Kevin Schröer ◽  
Lothar Brendel ◽  
Dietrich E. Wolf
Keyword(s):  
Molecular Dynamics ◽  
Thermal Resistance ◽  
Silicon Nanowires ◽  
Nonequilibrium Molecular Dynamics ◽  
Twist Boundaries

Interface Effect on Lattice Thermal Conductivities of Superlattice Nanowires

2004 ◽  
Author(s):  
Yunfei Chena ◽  
Deyu Li ◽  
Juekuan Yang ◽  
Zhonghua Ni ◽  
Jennifer R. Lukes
Keyword(s):  
Thermal Conductivity ◽  
Thermal Resistance ◽  
Effective Thermal Conductivity ◽  
Phonon Transport ◽  
Period Length ◽  
Interfacial Thermal Resistance ◽  
Boundary Scattering ◽  
Sectional Area ◽  
Cross Sectional ◽  
Interface Scattering

The nonequilibrium molecular dynamics (NEMD) method has been used to calculate the lattice thermal conductivities of Ar and Kr/Ar nanostructures in order to study the effects of interface scattering, boundary scattering, and elastic strain on lattice thermal conductivity. Results show that interface scattering poses significant resistance to phonon transport in superlattices and superlattice nanowires. The thermal conductivity of the Kr/Ar superlattice nanowire is only about 1/3 of that for pure Ar nanowires with the same cross sectional area and total length due to the additional interfacial thermal resistance. It is found that nanowire boundary scattering provides significant resistance to phonon transport. As the cross sectional area increases, the nanowire boundary scattering decreases, which leads to increased nanowire thermal conductivity. The ratio of the interfacial thermal resistance to the total effective thermal resistance increases from 30% for the superlattice nanowire to 42% for the superlattice film. Period length is another important factor affecting the effective thermal conductivity of the nanostructures. Increasing the period length will lead to increased acoustic mismatch between the adjacent layers, and hence increased interfacial thermal resistance. However, if the total length of the superlattice nanowire is fixed, reducing the period length will lead to decreased effective thermal conductivity due to the increased number of interfaces. Finally, it is found that the interfacial thermal resistance decreases as the reference temperature increases, which might be due to the inelastic interface scattering.

scholarly journals Modeling of Temperature-Dependent Noise in Silicon Nanowire FETs including Self-Heating Effects

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
P. Anandan ◽  
N. Malathi ◽  
N. Mohankumar
Keyword(s):  
Thermal Resistance ◽  
Silicon Nanowires ◽  
Thermal Noise ◽  
Silicon Nanowire ◽  
Channel Length ◽  
Temperature Dependent ◽  
Short Channel ◽  
Self Heating ◽  
Heating Effects ◽  
Temperature Dependent Model

Silicon nanowires are leading the CMOS era towards the downsizing limit and its nature will be effectively suppress the short channel effects. Accurate modeling of thermal noise in nanowires is crucial for RF applications of nano-CMOS emerging technologies. In this work, a perfect temperature-dependent model for silicon nanowires including the self-heating effects has been derived and its effects on device parameters have been observed. The power spectral density as a function of thermal resistance shows significant improvement as the channel length decreases. The effects of thermal noise including self-heating of the device are explored. Moreover, significant reduction in noise with respect to channel thermal resistance, gate length, and biasing is analyzed.

Plasmon-assisted interaction of Si with light, for cancer hyperthermia and electromagnetic energy harvest

2020 ◽  
Vol 92 (2) ◽  
pp. 20101
Author(s):  
Behnam Kheyraddini Mousavi ◽  
Morteza Rezaei Talarposhti ◽  
Farshid Karbassian ◽  
Arash Kheyraddini Mousavi
Keyword(s):  
Silicon Nanowires ◽  
Metallic Nanoparticles ◽  
Near Infrared ◽  
Optical Transition ◽  
Electromagnetic Energy ◽  
Energy Harvest ◽  
Absorption Enhancement ◽  
Ir Absorption ◽  
Absorption Mechanism ◽  
Near Ir

Metal-assisted chemical etching (MACE) is applied for fabrication of silicon nanowires (SiNWs). We have shown the effect of amorphous sheath of SiNWs by treating the nanowires with SF6 and the resulting reduction of absorption bandwidth, i.e. making SiNWs semi-transparent in near-infrared (IR). For the first time, by treating the fabricated SiNWs with copper containing HF∕H2O2∕H2O solution, we have generated crystalline nanowires with broader light absorption spectrum, up to λ = 1 μm. Both the absorption and photo-luminescence (PL) of the SiNWs are observed from visible to IR wavelengths. It is found that the SiNWs have PL at visible and near Infrared wavelengths, which may infer presence of mechanisms such as forbidden gap transitions other can involvement of plasmonic resonances. Non-radiative recombination of excitons is one of the reasons behind absorption of SiNWs. Also, on the dielectric metal interface, the absorption mechanism can be due to plasmonic dissipation or plasmon-assisted generation of excitons in the indirect band-gap material. Comparison between nanowires with and without metallic nanoparticles has revealed the effect of nanoparticles on absorption enhancement. The broader near IR absorption, paves the way for applications like hyperthermia of cancer while the optical transition in near IR also facilitates harvesting electromagnetic energy at a broad spectrum from visible to IR.

Sign in / Sign up

Export Citation Format

Share Document