Micrometer-scale WS2 atomic layers grown by alkali metal free gas-source chemical vapor deposition with H2S and WF6 precursors
Micrometer-scale WS2 atomic layers grown by alkali metal free gas-source chemical vapor deposition with H2S and WF6 precursors
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DOI：
10.35848/1347-4065/abd6d6
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发表时间：
2021-01
影响因子：
1.5
通讯作者：
Mitsuhiro Okada;N. Okada;W. Chang;Tetsuo Shimizu;T. Kubo;M. Ishihara;T. Irisawa
中科院分区：
文献类型：
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作者：
Mitsuhiro Okada;N. Okada;W. Chang;Tetsuo Shimizu;T. Kubo;M. Ishihara;T. Irisawa
二维半导体材料如MoS2和WS2的可缩放化学气相沉积（CVD）是将这些材料应用于真实的器件的关键技术。在这项工作中，我们展示了WS2晶体的生长行为，从气态前体，即H2S和WF6，在无碱金属的条件下。WS2晶体生长呈现逐层生长，其成核和横向生长等行为是一个热激活过程，晶粒尺寸和密度随温度的变化符合Arrhenius方程。所获得的WS2晶体显示质量可比从金属氧化物：WS2膜显示尖锐的光致发光峰宽为54毫电子伏和n型场效应晶体管操作。通过优化生长条件，我们获得了晶粒尺寸为1.5 μm的WS2晶体，这是迄今为止报道的在没有碱金属助催化剂的情况下用气体源CVD法生长的过渡金属二硫属化物的最大尺寸。
Scalable chemical vapor deposition (CVD) of two-dimensional semiconducting materials such as MoS2 and WS2 is a key technology for the application of these materials in real devices. In this work, we demonstrate the growth behavior of WS2 crystals from gaseous precursors, i.e. H2S and WF6, under alkali-metal-free conditions. The WS2 crystal growth exhibits layer-by-layer growth, and its behaviors, such as nucleation and lateral growth, are a thermally activated process: the temperature-dependent grain size and density are well fitted by the Arrhenius equation. The obtained WS2 crystal shows quality comparable to that obtained from metal oxides: the WS2 film shows sharp photoluminescence with a peak width of 54 meV and n-type field-effect transistor operation. Optimizing the growth conditions enabled us to obtain WS2 crystals with a grain size of ∼1.5 μm, which is the largest size ever reported for a transition-metal dichalcogenide grown by gas-source CVD without an alkali-metal promotor.