Large-Area Synthesis of Monolayer and Few-Layer MoSe₂Films on SiO₂Substrates

Abstract

We present successful synthesis of large area atomically thin MoSe2 films by selenization of MoO3 in a vapor transport chemical vapor deposition (CVD) system. The homogeneous thin film can reach an area of 1 × 1 cm(2) consisting primarily of monolayer and bilayer MoSe2 film. Scanning transmission electron microscopy (STEM) images reveal the highly crystalline nature of the thin film and the atomic structure of grain boundaries in monolayers. Raman and photoluminescence spectroscopy confirm the high quality of as-grown MoSe2 in optics, and electronic transport measurements highlight the potential applications of the sample in nanoelectronics.

Ultrafast, Broadband Photodetector Based on MoSe2/Silicon Heterojunction with Vertically Standing Layered Structure Using Graphene as Transparent Electrode

“…The prominent A 1g mode relates to the out‐of‐plane vibration of Se atoms, while the E 2g mode is associated with the in‐plane vibration of Mo and Se atoms (see the inset in Figure 1a). Prior research results indicate that the change in layer number of MoSe 2 nanosheets will cause a significant difference in the locations of scattering modes in Raman spectra; the E 2g vibration will redshift, whereas the A 1g vibration will blueshift, with increasing MoSe 2 layer number 20, 57. Considering the large thickness of the MoSe 2 film in this work, its Raman spectra are more likely to be identical to that of the MoSe 2 bulk material or multilayer nanosheets.…”

“…From the high‐resolution TEM (HRTEM) image at the junction interface (Figure 2d), we can see that there is a thin interfacial oxide layer (≈5 nm) formed between the Si substrate and the MoSe 2 film. Close investigation on the MoSe 2 film, Figure 2e, discloses the distinct vertically standing layered structure of the film, i.e., the growth direction of the (001) molecule planes of MoSe 2 are perpendicular to the Si substrate, in contrast the parallel growth of the MoSe 2 nanosheets fabricated by conventional chemical vapour deposition (CVD) method 57, 64. The dimension of individual crystal grains in the MoSe 2 film is 4–6 nm wide, corresponding to about 6–9 MoSe 2 monolayers (Figure 2e).…”

Booming Development of Group IV–VI Semiconductors: Fresh Blood of 2D Family

“…CVD‐grown graphene has made great breakthrough in the growth of large‐area graphene 17, 155, 156, 157, 158, 159, 160. Recently, the synthesis of 2DLMs via CVD methods has been illustrated in many reports especially for MoS 2 ,30, 31, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185 which also shows promising applications in electronics and optoelectronics. Up to now, there are several reports on synthesizing 2D GIVMCs nanoflakes via CVD method, which is still at the initial stage.…”

Repairing atomic vacancies in single-layer MoSe2 field-effect transistor and its defect dynamics

“…[23][24][25][26][27][28] The defects also cause more severe influence on the device performance since the quantum paths are greatly suppressed in the 2D electronic transport. 23,24,29 For the SLM FET, such defects lead to various carrier mobilities, 19,24,[30][31][32][33] and defect repairing is the focus of concern during these years. 17,28,34,35 Here we report that a simple drop of chemical solution may repair the defect-rich SLM FET, by which the carrier mobility increases from 0.1 to around 30 cm 2 /Vs.…”