Graphene and boron nitride lateral heterostructures for atomically thin circuitry
Graphene and boron nitride lateral heterostructures for atomically thin circuitry
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DOI：
10.1038/nature11408
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发表时间：
2012-08-30
期刊：
影响因子：
64.8
通讯作者：
Park, Jiwoong
中科院分区：
文献类型：
--
作者：
Levendorf, Mark P.;Kim, Cheol-Joo;Park, Jiwoong
对薄膜电性能的精确空间控制是现代集成电路生产的关键能力。尽管化学气相沉积方法的最新进展已经使得能够大规模生产本征和掺杂石墨烯（1-6）以及六方氮化硼（h-BN）（7-10），但是还没有实现在这些真正原子级薄的系统中横向异质结构的受控制造。石墨烯/h-BN界面特别令人感兴趣，因为已知不同原子组成的区域可以共存于连续的原子薄膜内（5，10），并且通过适当的控制，可以精确地设计带隙和磁性（11-13）。然而，先前报道的用于控制这些界面的方法具有基本限制，并且不能容易地与传统光刻集成（14-16）。在这里，我们报告了一个通用的和可扩展的过程，我们称之为“图案化再生”，它允许在空间上控制合成导电石墨烯和绝缘h-BN之间的横向结，以及本征和替代掺杂的石墨烯之间。我们证明，所得到的薄膜形成机械连续的片材跨越这些异质结。电导测量证实了h-BN区域的横向绝缘行为，而掺杂和未掺杂的石墨烯片的电学行为保持了优异的特性，具有低的薄层电阻和高的载流子迁移率。我们的研究结果代表了发展原子级薄集成电路的重要一步，并使电隔离的有源和无源元件嵌入在连续的，一个原子厚的片材，它可以被操纵和堆叠，形成复杂的设备在最终的厚度极限制造。
Precise spatial control over the electrical properties of thin films is the key capability enabling the production of modern integrated circuitry. Although recent advances in chemical vapour deposition methods have enabled the large-scale production of both intrinsic and doped graphene(1-6), as well as hexagonal boron nitride (h-BN)(7-10), controlled fabrication of lateral heterostructures in these truly atomically thin systems has not been achieved. Graphene/h-BN interfaces are of particular interest, because it is known that areas of different atomic compositions may coexist within continuous atomically thin films(5,10) and that, with proper control, the bandgap and magnetic properties can be precisely engineered(11-13). However, previously reported approaches for controlling these interfaces have fundamental limitations and cannot be easily integrated with conventional lithography(14-16). Here we report a versatile and scalable process, which we call 'patterned regrowth', that allows for the spatially controlled synthesis of lateral junctions between electrically conductive graphene and insulating h-BN, as well as between intrinsic and substitutionally doped graphene. We demonstrate that the resulting films form mechanically continuous sheets across these heterojunctions. Conductance measurements confirm laterally insulating behaviour for h-BN regions, while the electrical behaviour of both doped and undoped graphene sheets maintain excellent properties, with low sheet resistances and high carrier mobilities. Our results represent an important step towards developing atomically thin integrated circuitry and enable the fabrication of electrically isolated active and passive elements embedded in continuous, one-atom-thick sheets, which could be manipulated and stacked to form complex devices at the ultimate thickness limit.