Insights Into the Two-Dimensional MoS₂ Grown on AlGaN(GaN) Substrates by CVD Method

Abstract

Two-dimensional (2D) MoS 2 was grown on AlGaN(GaN) substrates by chemical vapor deposition (CVD) and 2D-3D MoS 2 -AlGaN(GaN) heterostructures were formed. The MoS 2 crystal on AlGaN surface has a mixed and irregular shape including single and multiple layers, while the single layer of triangular MoS 2 is basically prepared on GaN surface. Combined with theoretical first-principles analysis, it is found the adsorption of AlGaN to MoS 2 is lower than that of GaN, which leads to the deposition of MoS 2 molecules on AlGaN surface, forming multilayer shapes. In addition, Both the MoS 2 -AlGaN(GaN) heterostructures exhibit indirect band gaps and broad-band light absorption performances. Index Terms-Chemical vapor deposition, GaN substrate, heterostructure, two-dimensional MoS 2 . I. INTRODUCTIONA S ONE of the important members of two-dimensional (2D) transition metal chalcogenides, 2D semiconducting MoS 2 has high carrier mobility, excellent chemical stability and thermodynamic stability, which is very suitable for electronic and optoelectronic device applications [1], [2]. Since there is usually van der Waals (vdW) force between 2D MoS 2 layers, integrating it with other different semiconductor materials and constructing Manuscript

Optical characterizations of GaN/MoS2 van der Waals heterojunctions with different band alignments

“…This could be attributed to the noise signal originating from the Raman scattering of the sapphire substrate. 40) A similar PL result has also been reported in Ref. 41.…”