Comparison of Seeding Promoters in Growth of Tungsten Disulfide by Chemical Vapor Disposition.

Seeding promoters have been utilized to facilitate the growth of transition metal dichalcogenides via chemical vapor deposition (CVD). The choice of seeding promoter can significantly impact the resulting film's properties, including its crystallization, growth area, phase, and composition. Our study will investigate the effects of different seeding promoters on tungsten disulfide (WS₂) growth on sapphire, which is known to be challenging to control in terms of layer area, quality, and thickness. The seeding promoters we will be using in our study are sodium chloride (NaCl), zinc oxide/zinc sulfate (ZnO/ZnSO₄), and sodium sulfate (NaSO₄). We will analyze the effect of each seeding promoter on the properties of WS₂ to determine their correlation and identify the best promoter for future growth. To analyze the properties of WS₂films, we will use confocal laser microscopy, photoluminescence spectroscopy (PL), Raman spectroscopy, Fourier transform infrared microscopy (FTIR), and x-ray photoemission spectroscopy (XPS). Our focus will be on studying these films' photoluminescence, absorption, layer thickness, impurity, optical phonon modes, and bandgap.