title: HfSe2 thin films: 2D transition metal dichalcogenides grown by molecular beam epitaxy.
abstract: 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 ∼ 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.
authors.affiliation: Department of Materials Science and Engineering, University of Texas at Dallas , Richardson, Texas 75080, United States.
authors.forename: Ruoyu
authors.initials: R
authors.lastname: Yue
authors.forename: Adam T
authors.initials: AT
authors.lastname: Barton
authors.forename: Hui
authors.initials: H
authors.lastname: Zhu
authors.forename: Angelica
authors.initials: A
authors.lastname: Azcatl
authors.forename: Luis F
authors.initials: LF
authors.lastname: Pena
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Peng
authors.forename: Ning
authors.initials: N
authors.lastname: Lu
authors.forename: Lanxia
authors.initials: L
authors.lastname: Cheng
authors.forename: Rafik
authors.initials: R
authors.lastname: Addou
authors.forename: Stephen
authors.initials: S
authors.lastname: McDonnell
authors.forename: Luigi
authors.initials: L
authors.lastname: Colombo
authors.forename: Julia W P
authors.initials: JW
authors.lastname: Hsu
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Kim
authors.forename: Moon J
authors.initials: MJ
authors.lastname: Kim
authors.forename: Robert M
authors.initials: RM
authors.lastname: Wallace
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Hinkle
keywords: hafnium diselenide; heterostructure; transition metal dichalcogenides; tunnel field-effect transistors; van der Waals epitaxy