研究課題/領域番号 |
15K17987
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研究機関 | 九州大学 |
研究代表者 |
Wang Haidong 九州大学, 工学(系)研究科(研究院), 助教 (30729405)
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研究期間 (年度) |
2015-04-01 – 2017-03-31
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キーワード | suspended graphene / thermal conductivity / substrate effect / heat spreader |
研究実績の概要 |
The ultra-high thermal conductivity of graphene makes it a promising material for thermal management in micro/nano scales. Due to its atomic thickness, the graphene/substrate interaction could significantly limit the heat transport in graphene. In the present project, we precisely measured the thermal conductivity of suspended single-layer graphene (SLG) and investigate the substrate effect quantitatively. Some important progresses have been achieved in the last year. We have developed a novel method for fabricating suspended SLG nano-electronic device. Both intrinsic electrical and thermal conductivities of SLG can be measured simultaneously. The thermal conductivity of SLG is about 2300W/mK at room temperature, decreasing as temperature increases. Meanwhile, the nanohole defect and geometric size have notable effect on the thermal conductivity of SLG. The result also indicates that the electrons contribute less than 1% to the heat transport in graphene. The thermal conductivity of SLG supported by SiO2 substrate is 600 W/mK, only about 25% of the suspended SLG. This comparison demonstrates that the substrate effect play an important role in restricting the phonon transport in SLG even more than the nanohole defect and layer-layer interaction. In order to achieve high heat transport ability, the graphene needs to be released from the substrate. A new H-type sensor device has been developed as a prototype to use the suspended SLG as heat spreader in application.
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現在までの達成度 (区分) |
現在までの達成度 (区分)
1: 当初の計画以上に進展している
理由
The project has been smoothly carried out. The suspended SLG nano-electronic devices have been successfully fabricated. The thermal conductivity of SLG has been measured by T-type sensor. The experimental result and theoretical analysis have been published in the journal of Scientific Reports and Carbon. Two more manuscripts have been submitted and under review.
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今後の研究の推進方策 |
Because the high thermal conductivity of graphene only exists in a free-standing membrane without substrate interaction,the suspended structure is necessary for enhancing the heat transport. We designed a prototype of H-type sensor to study the feasibility of suspended graphene heat spreader. The experiment will be carried out in 2016.
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次年度使用額が生じた理由 |
The incurring amount needs to be used for purchasing necessary experimental materials and related consumables.
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次年度使用額の使用計画 |
I plan to purchase single and multi-layer graphene membranes and prepare suspended graphene sample for experiment.
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