Controlled Growth of Single-Crystal Graphene Wafers on Twin-Boundary-Free Cu(111) Substrates
Controlled Growth of Single-Crystal Graphene Wafers on Twin-Boundary-Free Cu(111) Substrates
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DOI：
10.1002/adma.202308802
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发表时间：
2023-11-29
影响因子：
29.4
通讯作者：
Liu，Zhongfan
中科院分区：
文献类型：
--
作者：
Zhu，Yeshu;Zhang，Jincan;Liu，Zhongfan
单晶石墨烯(SCG)晶片因其优异的性能和与硅基技术的兼容性而被需要来实现质量电子学和光电子学。近年来，利用单晶Cu(111)衬底作为外延衬底，可以控制合成高质量的SCG晶片。然而，目前在单晶蓝宝石衬底上磁控溅射制备的Cu(111)薄膜仍然存在面内孪晶界，这降低了SCG化学气相沉积的性能。这里展示了如何消除铜上的孪晶界并实现4英寸。≈结晶度为95%的Cu111晶片。在具有特定织构的铜膜上引入温度梯度，在整个铜片上形成反常的晶格生长。通过面外晶界的迁移消除了面内孪晶界。在得到的单晶铜(111)衬底上生长的SCG晶片具有更高的结晶度，具有97%取向的石墨烯微区。在室温下，103个器件的载流子迁移率平均可达7284cm2V−1s−1，方块电阻均匀，4英寸内的方块电阻只有5%的偏差。区域。
Single‐crystal graphene (SCG) wafers are needed to enable mass‐electronics and optoelectronics owing to their excellent properties and compatibility with silicon‐based technology. Controlled synthesis of high‐quality SCG wafers can be done exploiting single‐crystal Cu(111) substrates as epitaxial growth substrates recently. However, current Cu(111) films prepared by magnetron sputtering on single‐crystal sapphire wafers still suffer from in‐plane twin boundaries, which degrade the SCG chemical vapor deposition. Here, it is shown how to eliminate twin boundaries on Cu and achieve 4 in. Cu(111) wafers with ≈95% crystallinity. The introduction of a temperature gradient on Cu films with designed texture during annealing drives abnormal grain growth across the whole Cu wafer. In‐plane twin boundaries are eliminated via migration of out‐of‐plane grain boundaries. SCG wafers grown on the resulting single‐crystal Cu(111) substrates exhibit improved crystallinity with >97% aligned graphene domains. As‐synthesized SCG wafers exhibit an average carrier mobility up to 7284 cm2V−1s−1at room temperature from 103 devices and a uniform sheet resistance with only 5% deviation in 4 in. region.