Synthesis of NbSe2/Bilayer Nb-Doped WSe2 Heterostructure from Exfoliated WSe2 Flakes,Small Structures

当前位置： X-MOL 学术 › Small Struct. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Synthesis of NbSe2/Bilayer Nb-Doped WSe2 Heterostructure from Exfoliated WSe2 Flakes
Small Structures ( IF 13.9 ) Pub Date : 2024-02-12 , DOI: 10.1002/sstr.202300401
Van Tu Vu ₁ , Minh Chien Nguyen ₁ , Whan Kyun Kim _{2,

3} , Van Dam Do ₁ , Vu Khac Dat ₄ , Woo Jong Yu ₁

Affiliation

Forming heterostructures of 2D metals and semiconductors using chemical vapor deposition (CVD) has significant potential to effectively reduce contact resistance in electronic devices. However, semiconducting transition metal dichalcogenide (TMD) layers in metal–semiconductor heterostructures are currently restricted to monolayers despite the superior mobility and density of states in bilayer TMDs. Herein, NbSe₂/bilayer Nb-doped WSe₂ metal/semiconductor heterostructure from exfoliated WSe₂ flakes are synthesized first. The exfoliated WSe₂ bulk crystals on an Nb-coated substrate are heated to 950 °C under a flow of selenium vapor, and then the NbSe₂/bilayer Nb-doped WSe₂ heterostructures are formed. Statistics on the number of Nb-doped WSe₂ layers grown on a 1 cm × 1 cm CVD substrate shows that 65% of the Nb-doped WSe₂ layers are grown as bilayers. X-ray photoelectron spectroscopy, optical microscopy, and transmission electron microscopy clearly clarify the number of Nb-doped WSe₂ layers and heterostructure of NbSe₂/bilayer Nb-doped WSe₂. Electrical measurements using Cr contacts show that bilayer Nb-doped WSe₂ displays 7- and 10-times higher mobility and on/off ratio than monolayer Nb-doped WSe₂. The mobility and on/off ratio are further doubled in NbSe₂/bilayer Nb-doped WSe₂ contact compared to Cr/bilayer Nb-doped WSe₂ contact, attributed to a clean interface in vertical stack heterostructure, enhancing electrical performance.

中文翻译：

利用剥离的 WSe2 薄片合成 NbSe2/双层 Nb 掺杂 WSe2 异质结构

使用化学气相沉积 (CVD) 形成二维金属和半导体异质结构具有有效降低电子设备接触电阻的巨大潜力。然而，尽管双层TMD具有优异的迁移率和态密度，但金属-半导体异质结构中的半导体过渡金属二硫属化物（TMD）层目前仅限于单层。在此，首先从剥离的WSe ₂薄片合成NbSe ₂ /双层Nb掺杂的WSe ₂金属/半导体异质结构。在硒蒸气流下将Nb涂覆基底上剥离的WSe ₂块状晶体加热至950℃，然后形成NbSe ₂ /双层Nb掺杂WSe _{2异质结构。对在 1 cm × 1 cm CVD 衬底上生长的 Nb 掺杂 WSe}₂层数量的统计表明，65%的 Nb 掺杂 WSe ₂层生长为双层。 X射线光电子能谱、光学显微镜和透射电子显微镜清楚地阐明了Nb掺杂WSe ₂的层数和NbSe ₂ /双层Nb掺杂WSe ₂的异质结构。使用 Cr 接触的电学测量表明，双层 Nb 掺杂 WSe ₂的迁移率和开/关比比单层 Nb 掺杂 WSe ₂高 7 倍和 10 倍。与Cr/双层Nb掺杂WSe ₂接触相比， NbSe _{2 /双层Nb掺杂WSe}₂接触的迁移率和开/关比进一步加倍，这归因于垂直堆叠异质结构中的干净界面，从而增强了电性能。

更新日期：2024-02-12

点击分享查看原文

点击收藏

公开下载

阅读更多本刊新发论文