HfSe2 Thin Films: 2D Transition Metal Dichalcogenides Grown by Molecular Beam Epitaxy

作者：Yue Ruoyu; Barton Adam T; Zhu Hui; Azcatl Angelica; Pena Luis F; Wang Jian; Peng Xin; Lu Ning; Cheng Lanxia; Addou Rafik; McDonnell Stephen; Colombo Luigi; Hsu Julia W P; Kim Jiyoung; Kim Moon J; Wallace Robert M; Hinkle Christopher L^*

来源：ACS Nano, 2015, 9(1): 474-480.

DOI：10.1021/nn5056496

• hafnium diselenide
• van der Waals epitaxy
• heterostructure
• transition metal dichalcogenides
• tunnel field-effect transistors

In this work, we demonstrate the growth of HfSe2 thin films using molecular beam epitaxy. The relaxed growth criteria have allowed us to demonstrate layered, crystalline growth without misfit dislocations on other 2D substrates such as highly ordered pyrolytic graphite and MoS2. The HfSe2 thin films exhibit an atomically sharp interface with the substrates used, followed by flat, 2D layers with octahedral (1T) coordination. The resulting HfSe2 is slightly n-type with an indirect band gap of similar to 1.1 eV and a measured energy band alignment significantly different from recent DFT calculations. These results demonstrate the feasibility and significant potential of fabricating 2D material based heterostructures with tunable band alignments for a variety of nanoelectronic and optoelectronic applications.

• 出版日期2015-1