Texture control and growth mechanism of WSe 2 film prepared by rapid selenization of W film

Scalable Epitaxial Growth of WSe2 Thin Films on SiO2/Si via a Self-Assembled PtSe2 Buffer Layer

“…1e), the WSe 2 film without the Pt underlayer shows quite rough surface with embedded nanoflake-like structures (Fig. S3b,c), similar to the rough surface morphology reported by earlier works for large-area WSe 2 synthesis on dielectric substrates 15,21 .…”

“…S3a) reveal that the intensity of WSe 2 (00ℓ) is much weaker for the sample without the Pt underlayer. The much poor crystalline quality for the WSe 2 film directly grown on SiO 2 is the same as the previous report 15,21 . In additon, unlike a smooth surface observed for the sample with Pt underlayer (Fig.…”

“…Large-area CVD prepared WSe 2 films on glass substrates at a lower temperature from reaction of WCl 6 and diethyl diselenide have been reported 15 , but they are composed of either platelet or needle like crystalline structure with different orientations. Through a vapor transfer method 21,22 , highly textured WSe 2 films have been fabricated on insulating substrates, however, films with high crystallinity and scalability are still lacking. Inspired by the selenization method widely used in the fabrication of Cu(In 1−x Ga x )Se 2 (CIGS) solar cells 23,24 , here we report a new method for large-area epitaxial WSe 2 synthesis on SiO 2 /Si substrates.…”

Synthesis and Characterization of Highly Crystalline Vertically Aligned WSe2 Nanosheets

“…The attractive reported properties and potential applications of WSe 2 materials require a well-controlled synthesis, in terms of their structure, including the number of layers, crystallographic phase composition, or/and film morphology. For this purpose, different synthesis techniques, such as chemical-vapor transport using a sealed ampoule containing W and Se materials under a vacuum and heated at a high temperature [4,[12][13][14], chemical and mechanical exfoliation [15,16], physical techniques (molecular beam epitaxial growth [17], pulsed laser deposition [18], and magnetron sputtering of W in an Se-rich atmosphere [6]), chemical approaches (colloidal method [19,20] and electrodeposition [21]), and atmospheric pressure chemical vapor deposition (APCVD) [22][23][24][25][26], have been used to obtain WSe 2 . The majority of recent studies are focused on the synthesis of 2D WSe 2 , with domains of different shapes and sizes.…”

“…The majority of recent studies are focused on the synthesis of 2D WSe 2 , with domains of different shapes and sizes. Furthermore, only a few are dedicated to thin films' synthesis with a controlled morphology, orientation, and crystallography, although these characteristics depend on the production method and growth parameters [14,23,27]. We report here on a simple growth strategy using the APCVD technique to obtain vertically-aligned WSe 2 nanosheets by rapid selenization.…”