Search

Article

x

留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

Synthesis and pressure study of bubbles in hexagonal boron nitride interlayer

Jiang Cheng-Xin Chen Ling-Xiu Wang Hui-Shan Wang Xiu-Jun Chen Chen Wang Hao-Min Xie Xiao-Ming

Jiang Cheng-Xin, Chen Ling-Xiu, Wang Hui-Shan, Wang Xiu-Jun, Chen Chen, Wang Hao-Min, Xie Xiao-Ming. Synthesis and pressure study of bubbles in hexagonal boron nitride interlayer. Acta Phys. Sin., 2021, 70(6): 069801. doi: 10.7498/aps.70.20201482
Citation:

Synthesis and pressure study of bubbles in hexagonal boron nitride interlayer

Jiang Cheng-Xin, Chen Ling-Xiu, Wang Hui-Shan, Wang Xiu-Jun, Chen Chen, Wang Hao-Min, Xie Xiao-Ming
PDF
HTML
Get Citation
  • Hexagonal boron nitride (h-BN) is considered as an ideal substrate material for new electronic devices and nano-electromechanical (NEMS) devices, owing to its hexagonal network lattice structure and high chemical and mechanical stability. It can be used to seal gas with a long-term stability, and then has a big potential in further applications in electronics and NEMS. Recently, researchers have discovered that hydrogen atoms can penetrate multiple layers of h-BN non-destructively, forming the bubbles between layers, which can be used as NEMS devices. In this article, we investigate the effect of hydrogen plasma treatment duration on the size of h-BN bubbles. It is found that the size of bubbles becomes larger with the increase of treatment time while their distribution density decreases. It is also observed that the prepared h-BN bubbles have similar morphological characteristics, which are related to Young’s modulus of h-BN and interlayer van der Waals interaction. With the help of force-displacement curve measurement, it is obtained that the internal pressure is about 1—2 MPa for micro-sized bubbles, while the internal pressure of nano-sized bubbles can reach a value of GPa.
      PACS:
      98.38.Kx(Intercloud medium (ICM); hot and highly ionized gas; bubbles)
      52.25.Jm(Ionization of plasmas)
      07.10.Cm(Micromechanical devices and systems)
      Corresponding author: Wang Hao-Min, hmwang@mail.sim.ac.cn
    • Funds: Project supported by the National Key R&D Program of China (Grant No. 2017YFF0206106), the National Natural Science Foundation of China (Grant Nos. 51772317, 91964102), the Strategic Priority Research Program (B) of Chinese Academy of Sciences (Grant No. XDB30000000), the Shanghai “Super Postdoctor” Program, and the China Postdoctoral Science Foundation (Grant Nos. 2019T120366, 2019M651620)

    六方氮化硼(h-BN)由六角蜂窝结构上交替排列的硼原子和氮原子构成[1]. 作为一种宽带隙半导体, h-BN具有原子级平坦的表面, 没有任何表面悬挂键及电荷[2], 这使得它常被用作二维晶体的衬底或封装材料[3]. 此外, h-BN具有极高的热稳定性和化学稳定性. 即使是在大气环境下, 单层的h-BN在800 ℃高温下依然保持稳定[4], 使得h-BN常用作抗氧化层来保护易氧化的二维材料和器件[5]. 这种抗氧化性能说明h-BN可以有效地隔绝气体分子, 可以实现对气体的封装和保存, 是极端条件下信息器件和MEMS器件的理想衬底材料[58].

    与石墨烯材料类似[9], h-BN具有较高的弹性且可以封装气体分子. 得益于h-BN合适的晶格常数和堆垛结构[10], 气体分子难以穿透h-BN晶格[11], 因此气体可以在被捕获后保存在h-BN气泡中. 目前, 许多二维材料(例如石墨烯[1217]和二硫化钼[12,13,1820]等)均被用来尝试制备纳米气泡结构. 然而, 针对这种纳米气泡结构的制备, 大部分方案还停留在将机械剥离的二维材料薄层转移到衬底过程中的小概率气体捕获方案, 气泡结构的制备具有随机性且产率不高. 此外, 相关性质研究大多集中于石墨烯等二维材料, 针对h-BN气泡结构的制备和研究较少.

    最近, 作者所在课题组通过直接对h-BN片层进行氢等离子体处理, 实现了h-BN气泡的制备[21], 但h-BN纳米气泡的形貌和机械特性有待研究. 本文通过改变氢等离子体处理时间, 研究了h-BN气泡尺寸随处理时间的关系. 在气泡机械性质方面, 通过对h-BN气泡结构的原子力显微镜(AFM)测量发现气泡高度和气泡半径的比值几乎是恒定的. 理论分析发现该比值仅与h-BN材料的杨氏模量以及层间的范德瓦耳斯(vdW)相互作用有关. 为了得到h-BN纳米气泡内的气体压强, 采用了AFM的纳米压痕技术[2227]对气泡进行力-位移曲线的测量. 分析发现气泡内部的压力与层间vdW相互作用和气泡的最大高度有关.

    h-BN气泡的制备过程如下: 首先, h-BN由微机械剥离法解理到用氧等离子体清洗过的石英衬底上. 将带有h-BN片层的石英衬底装入配备有射频发生器的化学气相沉积反应炉中(MTI公司, 射频13.56 MHz), 功率范围为100—400 W. 样品温度可以在室温至1000 ℃范围内连续可调. 真空泵(GX100N干泵系统, Edwards)连接到化学气相沉积腔室, 以控制流速. 将样品加热到预设温度后, 设定流速为3 sccm (1 sccm = 1 mL/min)(对应气压约3 Pa)的氢气引入反应腔室, 最后打开射频等离子体源对样品进行处理.

    等离子体处理时间控制在90—150 min. 在氢等离子体处理期间, 氢气分子被离子化为氢离子或原子, 这些氢离子或原子足够小且具有数个电子伏(eV)的动能, 足以无损穿过h-BN的晶格, 最后在h-BN片层表面形成氢气气泡, 这些气泡区域的h-BN通常为多层, 厚度约为6 nm[21].

    可以通过AFM (Cypher S, Asylum Research)测量得到h-BN气泡的形貌特征. 图1为氢等离子体处理后在h-BN气泡的AFM形貌图. 几乎所有气泡都具有圆形或近似圆形的基底(图1(a)). 在气泡分布较密集的区域, 气泡间距比较近. 这些气泡通常较小, 半径小于300 nm (图1(b)). 对于尺寸较大的气泡, 它们的半径可达到约600 nm (图1(c)).

    图 1  h-BN气泡的典型AFM形貌图像 (a) 具有不同尺寸以及不同分布密集程度的h-BN纳米气泡形貌图像(标尺: 1 μm); (b), (c) 分别是图(a)中红色和橙色线框区域的放大AFM测量形貌图; 所有形貌图像共享右侧的标尺
    Fig. 1.  Typical AFM images of h-BN bubbles: (a) Topography of h-BN bubbles in different size and distribution density. Scale bar, 1 μm; (b), (c) AFM images taken from the red and orange box in panel (a) respectively. The scale of height sits on the right.

    所有的h-BN气泡样品在大气环境中进行保存, 以探索其结构随时间的稳定性. 通过在不同时间段对相同样品区域的光学显微镜测量(补充材料的图S1 (online)), 发现制备的h-BN气泡分布随时间变化没有发生明显改变. 对同一样品区域进行不同时间段的AFM测量(补充材料的图S2 (online)), 证实气泡结构随时间展现出较高的稳定性, 其尺寸随时间变化几乎保持不变. 其次, 针对单独h-BN气泡的多次AFM测量(补充材料的图S3 (online)), 发现在AFM探针等外力作用下, h-BN气泡结构能保持稳定, 未出现明显气体泄漏或结构破损. 因此, 制备的h-BN气泡样品能够实现长期的保存, 其结构随时间变化展现出高稳定性.

    不同时间的氢等离子体处理对h-BN气泡的影响如图2所示. 分别给出了处理时间在60, 90和120 min情况下, h-BN气泡的分布情况.

    图 2  氢等离子体处理不同时间后h-BN气泡分布情况 (a)−(c) 氢等离子体处理60, 90和120 min时, h-BN表面的气泡情况(标尺: 2 μm), 图(a)和图(b)中的插图分别是对应处理时间的单个气泡的AFM形貌图像, 图(a)插图的标尺为50 nm, 图(b)插图的标尺为400 nm; (d) 图(a)和图(b)的插图以及图(c)的气泡截面轮廓, 柱状图部分是在不同处理时间下气泡平均高度的统计
    Fig. 2.  Distribution of h-BN bubbles after hydrogen plasma treatment for different treatment duration. (a)−(c) AFM images of the h-BN bubbles after treated for 60, 90 and 120 min. Scale bar: 2 μm. The inserts in (a) and (b) are the AFM topography images of a single bubble corresponding to the processing time. The scale bar is 50 nm for insert in (a) and 400 nm for the insert in (b). (d) Cross-sectional profiles of bubbles in inserts of panels (a) and (b) and panel (c). The histogram part is the average bubble height under different processing times according to statistics.

    图2(a)所示是氢等离子体处理时间为60 min的情况, h-BN表面分布着密集的气泡, 他们具有很小的尺寸, 半径在40—50 nm, 高度仅有几纳米. 将处理时间延长到90 min后, 气泡的分布情况如图2(b)所示. 气泡分布的密集程度相比处理时间为60 min时有所降低, 但气泡尺寸明显增大, 半径达到500—600 nm, 且气泡高度达到了50 nm. 图2(c)反映的是处理时间为120 min的气泡分布情况, 气泡的半径达到了3 μm, 并且气泡最大高度有200 nm左右. 图2(a)(c)中的标尺均表示2 μm的尺度. 综合来看, 处理时间的延长会使得气泡的尺寸增大且气泡分布的密集程度降低. 气泡密集程度的降低是由于在气泡持续增大的过程中, 相邻的气泡发生了合并, 这一点在图2(c)中尤为明显, 大气泡的周围有零散的尺寸较小的气泡.

    为了清楚地分辨小尺寸的气泡, 图2(a)图2(b)的插图中给出了对应处理时间的单独h-BN气泡AFM形貌图, 这直观地反映出处理时间的延长会使得气泡尺寸增大. 图2(a)图2(b)插图中的气泡截面轮廓和图2(c)中的气泡轮廓统一在图2(d)中进行比较. 随着处理时间的延长, 气泡的形貌是整体扩大的过程, 气泡半径以及高度都随着处理时间的增加而增大. 图2(d)中的柱状图部分是对不同处理时间下气泡平均高度的统计. 气泡的高度在处理时间延长的情况下会整体增大. 因此, 延长氢等离子体处理时间有利于形成更大的h-BN气泡.

    气泡区域的h-BN虽然为多层, 但厚度有限, 气泡尺寸以及机械性能随h-BN层数的变化呈现弱相关性[28,29], 因此可以直接通过AFM对h-BN气泡的形貌结构进行测量, 进而提取不同尺寸气泡的截面轮廓并进行分析. 图3给出了气泡尺寸相关的统计信息. 气泡的最大高度与半径的比值(${h_{\max }}/R$)统计在图3(a)中. 统计结果反映出该比值趋向于一个定值, 说明${h_{\max }}/R$与气泡半径R以及体积V都不相关(${h_{\max }}/R$的另一组统计示例可参考补充材料的图S4 (online)). 图3(a)中的插图给出了典型的h-BN纳米气泡结构. 分析不同尺寸纳米气泡的尺寸比, 并将其统计在图3(b)中, 发现不同气泡的尺寸比都分布在固定值0.092的附近, 具体气泡的尺寸比与0.092的偏差范围仅在10%以内.

    图 3  气泡特征尺寸的统计分析 (a) 对不同半径气泡的尺寸比统计结果, 插图是h-BN气泡的结构示意图; (b) 具有不同尺寸比的气泡数量统计, 可以发现h-BN气泡的尺寸比集中在0.092附近, 橙色点代表气泡的尺寸比与0.092的偏差, 整体偏差值在10%范围以内(绿色区域)
    Fig. 3.  Characteristic analysis of bubbles. (a) Statistical results of size ratios hmax/R of bubbles with different radius. The inset is a schematic diagram of the h-BN bubble structure. (b) Statistics of bubble numbers with different size ratios. It can be found that the size ratio of h-BN bubbles is concentrated around 0.092. The orange point represents the deviation of the bubble size ratio from 0.092, and the overall deviation value is within 10% (green area).

    对此, 我们对h-BN气泡的形成过程进行了分析: 电离后的氢原子(离子)穿过网状h-BN晶格, 在层间结合成氢气分子从而形成气泡结构. 该气泡结构的气压会导致气泡区域的顶部h-BN发生拉伸形变. 最终, 气泡内外气压差、h-BN的形变张力和h-BN层间vdW作用力形成平衡.

    顶部h-BN通过vdW相互作用与h-BN衬底相结合. h-BN在气泡边缘的相互作用主要是vdW力、内外气压差以及h-BN因形变导致的刚度张力相互竞争的结果. h-BN的刚度由面内应力和与面外弯曲相关的能量共同决定. 其中, 面内应力可以由弹性理论[30]进行描述. 由于h-BN的结构与石墨烯相似, 面外形变会对面内刚度产生影响, 而面外弯曲程度可以通过弯曲刚度来进行描述. 面内应力和弯曲刚度对弹性能量的贡献取决于材料的形变尺度. 若形变尺度超过${l_{{\rm{anh}}}} \sim \sqrt {Y/\kappa } $ ($\kappa $表示弯曲刚度), 则可以忽略弯曲刚度的贡献[13,19]. 对于h-BN, ${l_{{\rm{anh}}}} < 1\;{\rm{nm}}$, 该尺度远远小于h-BN气泡的形变尺度, 因此可以忽略弯曲刚度的影响. 图3(a)的插图给出了h-BN气泡的结构示意图. 借助理论模型[13]可以得到气泡尺寸比的表达式为

    ${h_{\max }}/R = {\left( {{\rm{\pi }}\gamma /5cY} \right)^{1/4}},$

    (1)

    其中Y表示h-BN的杨氏模量, γ表示黏附能, c为无量纲常数. (1)式说明h-BN气泡的尺寸比仅与h-BN层间vdW作用和弹性能量有关, 与气泡内部所含气体的性质无关. 这与实际测量所表现出的恒定尺寸比相符合. 类似的工作同样也指出气泡尺寸比与黏附能和杨氏模量之间的关系, 并且展现出尺寸比恒定的特征[12,13,31].

    气泡内部的气体压强在不考虑外部应变的情况下可以表示为[13]

    $P = 4{\rm{\pi }}\gamma /(5{c_V}{h_{\max }}),$

    (2)

    这表明气泡内部的vdW压强受顶部h-BN和h-BN衬底之间的黏附能影响.

    为了实际测量h-BN气泡中的气体压强, 利用AFM的纳米压痕技术对气泡进行力-位移曲线的测量. 使用AFM探针在小距离范围内下压不同尺寸的气泡, 并记录相应的力-位移曲线(FDC). 为了避免在探针下压过程中破坏h-BN气泡, 设定了较小的探针压痕深度(约为15 nm). 图4(a)显示了不同尺寸气泡的FDC. 该图反映出随着气泡尺寸的增加, 要达到相同的下压深度($\delta $), 施加在探针上的力在逐渐减小. 这与(2)式所描述的压强与${h_{\max }}$之间的反比例关系一致.

    图 4  h-BN气泡内压强的分析 (a) 通过AFM测得的不同尺寸的h-BN气泡的力-位移曲线, 随着探针下压深度的增加, 所需的力也随之增大, 不同尺寸气泡的力-位移曲线表现出不同的斜率; (b) 从实际测得的力-位移数据中提取的vdW压强随探针下压深度的关系, 虚线为对应数据组的线性拟合结果; (c) vdW压强与气泡最大高度hmax的关系图, 实线部分是针对1/hmax的非线性拟合结果
    Fig. 4.  Pressure analysis inside h-BN bubbles. (a) Force-displacement curves of the bubbles with different sizes are measured by AFM, which shows the force increases while the tip goes deeper. The FDCs of different-sized bubbles have diverse slopes. (b) vdW pressure inside bubbles extracted from the experimental data in panel (a) as a function of the indentation depth. Dashed lines are linear fits. (c) vdW pressure as a function of ${h}_{\max}$, the solid line is fitted to ${1/h}_{\max}$.

    在AFM探针尖端的下压过程中, AFM系统检测到的力可能不仅来自气泡内部封装气体, 还来自顶部h-BN形变所产生的弹力. 施加到探针的力(F)和$\delta $之间的关系满足[13]:

    $F/\delta = d(\upsilon )Y{\left( {{h_{\max }}/R} \right)^2},$

    (3)

    其中$d(\upsilon )$也是与泊松比有关的无量纲常数. 这说明力与压痕深度呈线性关系, 因为对于相同的材料, 封装气泡的h-BN材料的杨氏模量和尺寸比(${h_{\max }}/R$)是固定的. 这与图4(a)中的测量数据描述的现象一致. 在探针的短距离下压过程中, 尖端与气泡之间的接触面积保持不变. 接触区域的压强为$P = $$ {P_{{\rm{tip}}}} = {F_{{\rm{tip}}}}/{S_{{\rm{tip}}}}$(其中${P_{{\rm{tip}}}}$表示探针测得的压强, ${F_{{\rm{tip}}}}$表示探针施加在气泡表面的力, ${S_{{\rm{tip}}}}$表示探针与气泡的接触面积), 由AFM系统测量的压强就是气泡内部的气体压强. 由vdW相互作用产生的压力与$\delta $${h_{\max }}$的关系如图4(b)图4(c)所示. 气泡内部的压强达到1—2 MPa. 气体压强与$\delta $${h_{\max }}$之间的关系均符合(2)式和(3)式所描述的特征.

    除了上述分析的尺寸在微米级的气泡, 在处理时间较短时, h-BN表面会得到较多纳米级的小尺寸气泡. 图5描述了典型的小气泡AFM形貌图像, 其在h-BN表面分布较密集, 气泡半径在几十纳米范围. 通过AFM图像的界面轮廓, 测得气泡高度仅有几纳米.

    图 5  在短时间氢等离子体处理下得到的小尺寸气泡  (a) 小尺寸气泡的分布情况(标尺: 150 nm); (b) 图(a)中标有数字记号的小气泡截面轮廓图
    Fig. 5.  Small size bubbles obtained under short-time hydrogen plasma treatment: (a) The distribution of small size bubbles, the size scale is 150 nm; (b) the cross-sectional profile view of the small bubbles marked with numbers in panel (a).

    对于该小尺寸的纳米气泡, 使用AFM纳米压痕技术很难对其内部压强进行测量, 主要原因有两个方面: 1)要获得较理想的纳米压痕曲线, AFM探针针尖至少需要在气泡区域下压5—15 nm的距离, 对于小尺寸气泡, 该下压距离已经超出了气泡的最大高度, 难以有效捕捉探针下压时的力-位移信号; 2)对于小尺寸气泡, 其横向尺度已经可以和探针的尖端半径可比, 在分析时就必须考虑针尖下压过程中, 针尖与气泡表面接触面积的变化, 这意味着上面分析的模型将不适用于小尺寸的气泡.

    尽管难以对小尺寸气泡进行纳米压痕测量, 不过有研究人员已经报道了小尺寸纳米气泡的压强与其特征尺寸的理论关系[13]. 气泡内气体压强与气泡最大高度的关系满足$P \sim \gamma /{h_{\max }}$, 据此可以估算出小尺寸气泡的内部压强达到了0.1—0.5 GPa.

    h-BN气泡的形貌图像和力-位移曲线通过Cypher AFM (Asylum Research)进行测量. 使用具有较软悬臂的探针(弹簧系数$k < 1 \;{\rm{N/m}}$, 尖端半径$r \approx 5 \;{\rm{nm}}$)来测量样品形貌. 探针与样品的作用力设定得较小, 以避免探针尖端与h-BN气泡之间的较大相互作用损坏气泡结构. 气泡的力-位移曲线测量需要具有较硬悬臂的探针. 更重要的是, 在测量之前需要校准探针悬臂的弹簧常数, 这有助于提高力与压痕深度关系的精确度. 因此, 我们使用轻敲模式的探针(AC160TS)来测量气泡的力-位移曲线. Cypher AFM系统能够自动校准该型号的探针, 以获得其实际的弹簧系数和悬臂灵敏度. 考虑到悬臂较硬, 测量样品形貌时需要将力尽可能调小, 同样是为了防止探针与样品较大的作用力破坏气泡结构. 在进行几次放大扫描以定位到气泡区域, 并在每个气泡的中央区域测量力-位移曲线.

    本文通过氢等离子体处理在h-BN表面制备了氢气纳米气泡, 其结构随时间变化展现出高稳定性. 借助AFM形貌测量, 研究了等离子体处理时间与气泡尺寸和分布的关系, 发现处理时间的延长会使得气泡的尺寸整体增大, 并且分布的密集程度会降低, 这是由于气泡增大过程中, 相邻气泡发生了合并.

    对h-BN气泡的尺寸统计发现其表现出一般特征, 该特征仅由h-BN的弹性性质决定. AFM测量结果表明, 不同尺寸的气泡具有相同的尺寸比. 分析指出该尺寸比仅受层间vdW相互作用和h-BN的弹性性能的影响.

    在h-BN气泡上进行AFM纳米压痕测量, 以研究气泡内部的气体压强. 发现压力与尖端压痕深度呈线性关系, 与理论分析相符合. 气泡内气体压强与气泡高度之间的关系表明, 较高的气泡通常会具有较低的压强. 对于微米尺度的h-BN气泡, 捕获在气泡内部的氢气压强有1—2 MPa. 而对于尺寸仅有几纳米的小气泡, 其内部气体压强经估算能达到0.1—0.5 GPa.

    [1]

    Corso M, Auwärter W, Muntwiler M, Tamai A, Greber T, Osterwalder J 2004 Science 303 217Google Scholar

    [2]

    Decker R, Wang Y, Brar V W, Regan W, Tsai H Z, Wu Q, Gannett W, Zettl A, Crommie M F 2011 Nano Lett. 11 2291Google Scholar

    [3]

    Dean C R, Young A F, Meric I, et al. 2010 Nat. Nanotechnol. 5 722Google Scholar

    [4]

    Liu L, Ryu S, Tomasik M R, et al. 2008 Nano Lett. 8 1965Google Scholar

    [5]

    Liu Z, Gong Y, Zhou W, et al. 2013 Nat. Commun. 4 2541Google Scholar

    [6]

    Xu M, Liang T, Shi M, Chen H 2013 Chem. Rev. 113 3766Google Scholar

    [7]

    Li L H, Cervenka J, Watanabe K, Taniguchi T, Chen Y 2014 ACS Nano 8 1457Google Scholar

    [8]

    Falin A, Cai Q, Santos E J G, et al. 2017 Nat. Commun. 8 1Google Scholar

    [9]

    Bunch J S, Verbridge S S, Alden J S, et al. 2008 Nano Lett. 8 2458Google Scholar

    [10]

    Liu L, Feng Y P, Shen Z X 2003 Phys. Rev. B 68 104102Google Scholar

    [11]

    Ko H, Lee J S, Kim S M 2018 Appl. Sci. Convergence Technol. 27 144Google Scholar

    [12]

    Dai Z, Hou Y, Sanchez D A, Wang G, Brennan C J, Zhang Z, Liu L, Lu N 2018 Phys. Rev. Lett. 121 266101Google Scholar

    [13]

    Khestanova E, Guinea F, Fumagalli L, Geim A K, Grigorieva I V 2016 Nat. Commun. 7 12587Google Scholar

    [14]

    Wang G, Dai Z, Wang Y, Tan P, Liu L, Xu Z, Wei Y, Huang R, Zhang Z 2017 Phys. Rev. Lett. 119 036101Google Scholar

    [15]

    Zhang B, Jiang L, Zheng Y 2019 Phys. Rev. B 99 245410Google Scholar

    [16]

    Hu X, Gong X, Zhang M, Lu H, Xue Z, Mei Y, Chu P K, An Z, Di Z 2020 Small 16 1907170Google Scholar

    [17]

    Georgiou T, Britnell L, Blake P, Gorbachev R V, Gholinia A, Geim A K, Casiraghi C, Novoselov K S 2011 Appl. Phys. Lett. 99 093103Google Scholar

    [18]

    Huang P, Guo D, Xie G, Li J 2018 Phys. Chem. Chem. Phys. 20 18374Google Scholar

    [19]

    Chirolli L, Prada E, Guinea F, Roldan R, San-Jose P 2019 2D Mater. 6 025010Google Scholar

    [20]

    Tyurnina A V, Bandurin D A, Khestanova E, Kravets V G, Koperski M, Guinea F, Grigorenko A N, Geim A K, Grigorieva I V 2019 ACS Photonics 6 516Google Scholar

    [21]

    He L, Wang H, Chen L, et al. 2019 Nat. Commun. 10 2815Google Scholar

    [22]

    Cooper R C, Lee C, Marianetti C A, Wei X, Hone J, Kysar J W 2013 Phys. Rev. B 87 035423Google Scholar

    [23]

    Castellanos-Gomez A, Poot M, Steele G A, van der Zant H S J, Agraït N, Rubio-Bollinger G 2012 Adv. Mater. 24 772Google Scholar

    [24]

    Liu K, Yan Q, Chen M, Fan W, Sun Y, Suh J, Fu D, Lee S, Zhou J, Tongay S, Ji J, Neaton J B, Wu J 2014 Nano Lett. 14 5097Google Scholar

    [25]

    Lee C, Wei X, Kysar J W, Hone J 2008 Science 321 385Google Scholar

    [26]

    López-Polín G, Gómez-Navarro C, Parente V, Guinea F, Katsnelson M I, Pérez-Murano F, Gómez-Herrero J 2015 Nat. Phys. 11 26Google Scholar

    [27]

    Wei X, Meng Z, Ruiz L, Xia W, Lee C, Kysar J W, Hone J C, Keten S, Espinosa H D 2016 ACS Nano 10 1820Google Scholar

    [28]

    Wang G, Dai Z, Xiao J, Feng S, Weng C, Liu L, Xu Z, Huang R, Zhang Z 2019 Phys. Rev. Lett. 123 116101Google Scholar

    [29]

    Wood J D, Harvey C M, Wang S 2017 Nat. Commun. 8 1952Google Scholar

    [30]

    Landau L D, Lifshitz E M, Sykes J B, Reid W H, Dill E H 1960 Phys. Today 13 44Google Scholar

    [31]

    Wang P, Gao W, Cao Z, Liechti K M, Huang R 2013 J. Appl. Mech. 80 040905Google Scholar

    期刊类型引用(0)

    其他类型引用(1)

  • 图 1  h-BN气泡的典型AFM形貌图像 (a) 具有不同尺寸以及不同分布密集程度的h-BN纳米气泡形貌图像(标尺: 1 μm); (b), (c) 分别是图(a)中红色和橙色线框区域的放大AFM测量形貌图; 所有形貌图像共享右侧的标尺

    Figure 1.  Typical AFM images of h-BN bubbles: (a) Topography of h-BN bubbles in different size and distribution density. Scale bar, 1 μm; (b), (c) AFM images taken from the red and orange box in panel (a) respectively. The scale of height sits on the right.

    图 2  氢等离子体处理不同时间后h-BN气泡分布情况 (a)−(c) 氢等离子体处理60, 90和120 min时, h-BN表面的气泡情况(标尺: 2 μm), 图(a)和图(b)中的插图分别是对应处理时间的单个气泡的AFM形貌图像, 图(a)插图的标尺为50 nm, 图(b)插图的标尺为400 nm; (d) 图(a)和图(b)的插图以及图(c)的气泡截面轮廓, 柱状图部分是在不同处理时间下气泡平均高度的统计

    Figure 2.  Distribution of h-BN bubbles after hydrogen plasma treatment for different treatment duration. (a)−(c) AFM images of the h-BN bubbles after treated for 60, 90 and 120 min. Scale bar: 2 μm. The inserts in (a) and (b) are the AFM topography images of a single bubble corresponding to the processing time. The scale bar is 50 nm for insert in (a) and 400 nm for the insert in (b). (d) Cross-sectional profiles of bubbles in inserts of panels (a) and (b) and panel (c). The histogram part is the average bubble height under different processing times according to statistics.

    图 3  气泡特征尺寸的统计分析 (a) 对不同半径气泡的尺寸比统计结果, 插图是h-BN气泡的结构示意图; (b) 具有不同尺寸比的气泡数量统计, 可以发现h-BN气泡的尺寸比集中在0.092附近, 橙色点代表气泡的尺寸比与0.092的偏差, 整体偏差值在10%范围以内(绿色区域)

    Figure 3.  Characteristic analysis of bubbles. (a) Statistical results of size ratios hmax/R of bubbles with different radius. The inset is a schematic diagram of the h-BN bubble structure. (b) Statistics of bubble numbers with different size ratios. It can be found that the size ratio of h-BN bubbles is concentrated around 0.092. The orange point represents the deviation of the bubble size ratio from 0.092, and the overall deviation value is within 10% (green area).

    图 4  h-BN气泡内压强的分析 (a) 通过AFM测得的不同尺寸的h-BN气泡的力-位移曲线, 随着探针下压深度的增加, 所需的力也随之增大, 不同尺寸气泡的力-位移曲线表现出不同的斜率; (b) 从实际测得的力-位移数据中提取的vdW压强随探针下压深度的关系, 虚线为对应数据组的线性拟合结果; (c) vdW压强与气泡最大高度hmax的关系图, 实线部分是针对1/hmax的非线性拟合结果

    Figure 4.  Pressure analysis inside h-BN bubbles. (a) Force-displacement curves of the bubbles with different sizes are measured by AFM, which shows the force increases while the tip goes deeper. The FDCs of different-sized bubbles have diverse slopes. (b) vdW pressure inside bubbles extracted from the experimental data in panel (a) as a function of the indentation depth. Dashed lines are linear fits. (c) vdW pressure as a function of ${h}_{\max}$, the solid line is fitted to ${1/h}_{\max}$.

    图 5  在短时间氢等离子体处理下得到的小尺寸气泡  (a) 小尺寸气泡的分布情况(标尺: 150 nm); (b) 图(a)中标有数字记号的小气泡截面轮廓图

    Figure 5.  Small size bubbles obtained under short-time hydrogen plasma treatment: (a) The distribution of small size bubbles, the size scale is 150 nm; (b) the cross-sectional profile view of the small bubbles marked with numbers in panel (a).

  • [1]

    Corso M, Auwärter W, Muntwiler M, Tamai A, Greber T, Osterwalder J 2004 Science 303 217Google Scholar

    [2]

    Decker R, Wang Y, Brar V W, Regan W, Tsai H Z, Wu Q, Gannett W, Zettl A, Crommie M F 2011 Nano Lett. 11 2291Google Scholar

    [3]

    Dean C R, Young A F, Meric I, et al. 2010 Nat. Nanotechnol. 5 722Google Scholar

    [4]

    Liu L, Ryu S, Tomasik M R, et al. 2008 Nano Lett. 8 1965Google Scholar

    [5]

    Liu Z, Gong Y, Zhou W, et al. 2013 Nat. Commun. 4 2541Google Scholar

    [6]

    Xu M, Liang T, Shi M, Chen H 2013 Chem. Rev. 113 3766Google Scholar

    [7]

    Li L H, Cervenka J, Watanabe K, Taniguchi T, Chen Y 2014 ACS Nano 8 1457Google Scholar

    [8]

    Falin A, Cai Q, Santos E J G, et al. 2017 Nat. Commun. 8 1Google Scholar

    [9]

    Bunch J S, Verbridge S S, Alden J S, et al. 2008 Nano Lett. 8 2458Google Scholar

    [10]

    Liu L, Feng Y P, Shen Z X 2003 Phys. Rev. B 68 104102Google Scholar

    [11]

    Ko H, Lee J S, Kim S M 2018 Appl. Sci. Convergence Technol. 27 144Google Scholar

    [12]

    Dai Z, Hou Y, Sanchez D A, Wang G, Brennan C J, Zhang Z, Liu L, Lu N 2018 Phys. Rev. Lett. 121 266101Google Scholar

    [13]

    Khestanova E, Guinea F, Fumagalli L, Geim A K, Grigorieva I V 2016 Nat. Commun. 7 12587Google Scholar

    [14]

    Wang G, Dai Z, Wang Y, Tan P, Liu L, Xu Z, Wei Y, Huang R, Zhang Z 2017 Phys. Rev. Lett. 119 036101Google Scholar

    [15]

    Zhang B, Jiang L, Zheng Y 2019 Phys. Rev. B 99 245410Google Scholar

    [16]

    Hu X, Gong X, Zhang M, Lu H, Xue Z, Mei Y, Chu P K, An Z, Di Z 2020 Small 16 1907170Google Scholar

    [17]

    Georgiou T, Britnell L, Blake P, Gorbachev R V, Gholinia A, Geim A K, Casiraghi C, Novoselov K S 2011 Appl. Phys. Lett. 99 093103Google Scholar

    [18]

    Huang P, Guo D, Xie G, Li J 2018 Phys. Chem. Chem. Phys. 20 18374Google Scholar

    [19]

    Chirolli L, Prada E, Guinea F, Roldan R, San-Jose P 2019 2D Mater. 6 025010Google Scholar

    [20]

    Tyurnina A V, Bandurin D A, Khestanova E, Kravets V G, Koperski M, Guinea F, Grigorenko A N, Geim A K, Grigorieva I V 2019 ACS Photonics 6 516Google Scholar

    [21]

    He L, Wang H, Chen L, et al. 2019 Nat. Commun. 10 2815Google Scholar

    [22]

    Cooper R C, Lee C, Marianetti C A, Wei X, Hone J, Kysar J W 2013 Phys. Rev. B 87 035423Google Scholar

    [23]

    Castellanos-Gomez A, Poot M, Steele G A, van der Zant H S J, Agraït N, Rubio-Bollinger G 2012 Adv. Mater. 24 772Google Scholar

    [24]

    Liu K, Yan Q, Chen M, Fan W, Sun Y, Suh J, Fu D, Lee S, Zhou J, Tongay S, Ji J, Neaton J B, Wu J 2014 Nano Lett. 14 5097Google Scholar

    [25]

    Lee C, Wei X, Kysar J W, Hone J 2008 Science 321 385Google Scholar

    [26]

    López-Polín G, Gómez-Navarro C, Parente V, Guinea F, Katsnelson M I, Pérez-Murano F, Gómez-Herrero J 2015 Nat. Phys. 11 26Google Scholar

    [27]

    Wei X, Meng Z, Ruiz L, Xia W, Lee C, Kysar J W, Hone J C, Keten S, Espinosa H D 2016 ACS Nano 10 1820Google Scholar

    [28]

    Wang G, Dai Z, Xiao J, Feng S, Weng C, Liu L, Xu Z, Huang R, Zhang Z 2019 Phys. Rev. Lett. 123 116101Google Scholar

    [29]

    Wood J D, Harvey C M, Wang S 2017 Nat. Commun. 8 1952Google Scholar

    [30]

    Landau L D, Lifshitz E M, Sykes J B, Reid W H, Dill E H 1960 Phys. Today 13 44Google Scholar

    [31]

    Wang P, Gao W, Cao Z, Liechti K M, Huang R 2013 J. Appl. Mech. 80 040905Google Scholar

  • [1] Zhang Xue-Song, Fan Zhen-Zhong, Tong Qi-Lei, Fu Yuan-Feng. Analysis of nanobubble collapse process by molecular simulation method. Acta Physica Sinica, 2024, 73(20): 204701. doi: 10.7498/aps.73.20241105
    [2] Wang Fan-Fan, Chen Dong, Yuan Jun, Zhang Zhu-Feng, Jiang Tao, Zhou Jun. Interlayer angle dependence of photoelectric properties of Sb/SnC van der Waals heterojunction and its application. Acta Physica Sinica, 2024, 73(22): 227101. doi: 10.7498/aps.73.20241138
    [3] Sun Ting-Yu, Wu Liang, He Xian-Juan, Jiang Nan, Zhou Wen-Zhe, Ouyang Fang-Ping. Effect of strain and electric field on electronic structure and optical properties of Ga2SeTe/In2Se3 heterojunction. Acta Physica Sinica, 2023, 72(7): 076301. doi: 10.7498/aps.72.20222250
    [4] Tang Jia-Xin, Li Zhan-Hai, Deng Xiao-Qing, Zhang Zhen-Hua. Electrical contact characteristics and regulatory effects of GaN/VSe2 van der Waals heterojunction. Acta Physica Sinica, 2023, 72(16): 167101. doi: 10.7498/aps.72.20230191
    [5] Huang Min, Li Zhan-Hai, Cheng Fang. Tunable electronic structures and interface contact in graphene/C3N van der Waals heterostructures. Acta Physica Sinica, 2023, 72(14): 147302. doi: 10.7498/aps.72.20230318
    [6] Jia Yan-Wei, He Jian, He Meng, Zhu Xiao-Hua, Zhao Shang-Man, Liu Jin-Long, Chen Liang-Xian, Wei Jun-Jun, Li Cheng-Ming. Synthesis of h-BN/diamond heterojunctions and its electrical characteristics. Acta Physica Sinica, 2022, 71(22): 228101. doi: 10.7498/aps.71.20220995
    [7] Yao Yi-Zhou, Cao Dan, Yan Jie, Liu Xue-Yin, Wang Jian-Feng, Jiang Zhou-Ting, Shu Hai-Bo. A first-principles study on environmental stability and optoelectronic properties of bismuth oxychloride/ cesium lead chloride van der Waals heterojunctions. Acta Physica Sinica, 2022, 71(19): 197901. doi: 10.7498/aps.71.20220544
    [8] Zhang Lun, Chen Hong-Li, Yi Yu, Zhang Zhen-Hua. Electronic and optical properties and quantum tuning effects of As/Hfs2 van der Waals heterostructure. Acta Physica Sinica, 2022, 71(17): 177304. doi: 10.7498/aps.71.20220371
    [9] Kong Yu-Han, Wang Rong, Xu Ming-Sheng. Photoluminescence properties of CuPc/MoS2 van der Waals heterostructure. Acta Physica Sinica, 2022, 71(12): 128103. doi: 10.7498/aps.71.20220132
    [10] Wu Min, Fei Hong-Ming, Lin Han, Zhao Xiao-Dan, Yang Yi-Biao, Chen Zhi-Hui. Design of asymmetric transmission of photonic crystal heterostructure based on two-dimensional hexagonal boron nitride material. Acta Physica Sinica, 2021, 70(2): 028501. doi: 10.7498/aps.70.20200741
    [11] Liao Jun-Yi, Wu Juan-Xia, Dang Chun-He, Xie Li-Ming. Methods of transferring two-dimensional materials. Acta Physica Sinica, 2021, 70(2): 028201. doi: 10.7498/aps.70.20201425
    [12] Xu Xiang, Zhang Ying, Yan Qing, Liu Jing-Jing, Wang Jun, Xu Xin-Long, Hua Deng-Xin. Photochemical properties of rhenium disulfide/graphene heterojunctions with different stacking structures. Acta Physica Sinica, 2021, 70(9): 098203. doi: 10.7498/aps.70.20201904
    [13] Wang Xiao-Feng, Tao Gang, Xu Ning, Wang Peng, Li Zhao, Wen Peng. Molecular dynamics analysis of shock wave-induced nanobubble collapse in water. Acta Physica Sinica, 2021, 70(13): 134702. doi: 10.7498/aps.70.20210058
    [14] Wu Tian, Yao Meng-Li, Long Meng-Qiu. First principle calculations of interface interactions and photoelectric properties of perovskite CsPbX3 (X=Cl, Br, I) and penta-graphene van der Waals heterostructures. Acta Physica Sinica, 2021, 70(5): 056301. doi: 10.7498/aps.70.20201246
    [15] Sun Zhi-Hai, Huang Qiang, Zhang Ying, Huang Peng-Ru, Zhi Hui-Yin, Zou Yong-Jin, Xu Fen, Sun Li-Xian. First-principle calculation study of (CN)3VB defect in hexagonal boron nitride monolayer. Acta Physica Sinica, 2021, 70(3): 033102. doi: 10.7498/aps.70.20201364
    [16] Zhang Fang, Jia Li-Qun, Sun Xian-Ting, Dai Xian-Qi, Huang Qi-Xiang, Li Wei. Tuning Schottky barrier in graphene/InSe van der Waals heterostructures by electric field. Acta Physica Sinica, 2020, 69(15): 157302. doi: 10.7498/aps.69.20191987
    [17] Chen Ling-Xiu, Wang Hui-Shan, Jiang Cheng-Xin, Chen Chen, Wang Hao-Min. Synthesis and characterization of graphene nanoribbons on hexagonal boron nitride. Acta Physica Sinica, 2019, 68(16): 168102. doi: 10.7498/aps.68.20191036
    [18] Wang Bo, Fang Yu-Long, Yin Jia-Yun, Liu Qing-Bin, Zhang Zhi-Rong, Guo Yan-Min, Li Jia, Lu Wei-Li, Feng Zhi-Hong. Effect of surface pretreatment on GaN van der Waals epitaxy growth on graphene. Acta Physica Sinica, 2017, 66(24): 248101. doi: 10.7498/aps.66.248101
    [19] Zhang Zeng-Xing, Li Dong. Novel p-n junctions based on ambipolar two-dimensional crystals. Acta Physica Sinica, 2017, 66(21): 217302. doi: 10.7498/aps.66.217302
    [20] Liu Meng-Xi, Zhang Yan-Feng, Liu Zhong-Fan. Scanning tunneling microscopy study of in-plane graphene-hexagonal boron nitride heterostructures. Acta Physica Sinica, 2015, 64(7): 078101. doi: 10.7498/aps.64.078101
  • 期刊类型引用(0)

    其他类型引用(1)

  • supplement 069801-20201482补充材料.pdf supplement
Metrics
  • Abstract views:  6950
  • PDF Downloads:  149
  • Cited By: 1
Publishing process
  • Received Date:  06 September 2020
  • Accepted Date:  08 November 2020
  • Available Online:  02 March 2021
  • Published Online:  20 March 2021

/

返回文章
返回