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SCIENCE CHINA Information Sciences, Volume 64 , Issue 4 : 140401(2021) https://doi.org/10.1007/s11432-020-3151-5

Filling the gap: thermal properties and device applications of graphene

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  • ReceivedNov 10, 2020
  • AcceptedDec 28, 2020
  • PublishedMar 2, 2021

Abstract


Acknowledgment

This work was supported in part by China Electronics Technology Group Corporation, Institute of Information Science (Grant No. H1125), National Natural Science Foundation of China (Grant Nos. 62022047, 61874065, 51861145202), National Key RD Program (Grant No. 2016YFA0200400), Research Fund from Beijing Innovation Center for Future Chip and the Independent Research Program of Tsinghua University (Grant No. 20193080047), Young Elite Scientists Sponsorship Program by CAST (Grant No. 2018QNRC001), and Fok Ying-Tong Education Foundation (Grant No. 171051).


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  • Figure 1

    (Color online) Schematic of theory & modeling, experiment and device application of graphene. Gaps exist between theories of different scales and between experimental results and actual effect.

  • Figure 2

    (Color online) Methods used for measurement of thermal conductivity of 2D materials [47].

  • Figure 3

    (Color online) Schematic of the experiment showing the excitation laser light focused on a graphene layer suspended across a trench. The focused laser light creates a local hot spot and generates a heat wave inside SLG propagating toward heat sinks [2].

  • Figure 4

    (Color online) Schematic of the “heat spreader method" to measure the in-plane $\kappa$ of graphene encased in a film of ${\rm~SiO}_2$ [51,52].

  • Figure 5

    (Color online) Schematic of our FDTR micro-scope. A digitally modulated pump laser heats the sample while a probe beam monitors the surface reflectivity. A balanced photodetector is used to improve the signal to noise ratio. A piezo stage is used to scan the sample for imaging [55].

  • Figure 6

    (Color online) (a) Schematic of the simulation structure. The thicknesses are not to scale [69]. (b) Temperature distribution obtained by finite element simulation. (c)–(e) Hot spot temperature before and after graphene is transferred onto the chip with the data from [70,71].

  • Figure 7

    (Color online) (a) Demonstration of principle of TIM [80]@Copyright 2020 the American Chemical Society. protectłinebreak (b) Composites' TC with different graphene layers, with data from [81].

  • Figure 8

    (Color online) Simulation models of vertical graphene (a) nanowalls [93]and (b) arrays [94].

  • Table 1  

    Table 1Summary of computational results of $\kappa$ of graphene at room temperature (RT)

    $\kappa$ (W$\cdot~{\rm~m}^{-1}\cdot~{\rm~K}^{-1}$ Method Comment Ref.
    $\sim$2350 BTE $L=10~{\mu}$m [21]
    480–850 GK-MD $\kappa$ depends on stacking order [22]
    2000–5000 Valence force field, BTE Strong width dependence [23]
    8000–10000 MD, Tersoff Square graphene sheet [24]
  • Table 2  

    Table 2Summary of TC of graphene in experiments

    $\kappa~({\rm~W}\cdot~{\rm~m}^{-1}\cdot~{\rm~K}^{-1})$MethodMaterial type Ref.
    3[2]40mm
    $\sim(4.84\pm~0.44)\times~10^3~-(5.30\pm~0.48)\times~10^3$
    5[2]45mm
    Optothermal Raman spectroscopy technique
    3[2]45mm
    Suspended exfoliated single-layer graphene (SLG), room temperature (RT)
    3[2]*[2]
    cmidrule1-1cmidrule3-4
    1[1]*$\sim$ 3000–5300
    1[1]45mm
    Suspended exfoliated SLG, RT
    1[1]*[48]
    cmidrule1-1cmidrule3-4
    1[1]*$\sim$ 3080–5150
    1[1]45mm
    Suspended exfoliated SLG, RT
    1[1]*[14]
    2[2]*$\sim$ 1500–5000
    2[2]45mm
    Optothermal Raman spectroscopy technique $+$ electrical burning
    2[2]48mm
    Suspended chemical vapor deposition (CVD) graphene, RT
    2[2]*[49]
    2[2]*$\sim~2500$
    4[4]45mm
    Optothermal Raman spectroscopy technique
    2[2]45mm
    Suspended CVD graphene, 350 K
    2[2]*[50]
    cmidrule1-1cmidrule3-4
    1[1]*$\sim~1400$
    1[1]45mm
    Suspended CVD graphene, 500 K
    1[1]*[50]
    cmidrule1-1cmidrule3-4
    1[1]*$\sim~630$
    1[1]45mm
    Graphene membrane, 600 K
    1[1]*[50]
    2[2]*below 160
    2[2]45mm
    Heat spreader method ($3\omega$ method)
    2[2]45mm
    Exfoliated SLG encased within silicon dioxide, RT
    2[2]*[51,52]
    2[2]40mm
    $\sim~7000$ (crude estimate)
    2[2]45mm
    All electrical, $3\omega$ method
    2[2]45mm
    Substrate-supported CVD graphene, RT
    2[2]*[49]
    2[2]*$\sim~600$
    2[2]45mm
    Thermal bridge
    2[2]45mm
    SLG exfoliated on a silicon dioxide support
    2[2]*[53]
    2[2]*$\sim370$
    2[2]45mm
    Laser heating
    2[2]45mm
    Exfoliated graphene supported on ${\rm~SiO}_2$, RT
    2[2]*[50]