MoS2 Thin Films Grown by Sulfurization of DC Sputtered Mo Thin Films on Si/SiO2 and C-Plane Sapphire Substrates


Akcay N., Tivanov M., ÖZÇELİK S.

Journal of Electronic Materials, vol.50, pp.1452-1466, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 50
  • Publication Date: 2021
  • Doi Number: 10.1007/s11664-020-08687-6
  • Journal Name: Journal of Electronic Materials
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Applied Science & Technology Source, Chemical Abstracts Core, Chimica, Compendex, Computer & Applied Sciences, INSPEC
  • Page Numbers: pp.1452-1466
  • Keywords: Transition metal dichalcogenides, MoS2 films, molybdenum disulfide, sulfurization, CVD, FTIR, LARGE-AREA, OPTICAL-PROPERTIES, LAYER MOS2, PHOTOLUMINESCENCE, PERFORMANCE, MULTILAYER, UNIFORM
  • Gazi University Affiliated: Yes

Abstract

© 2021, The Minerals, Metals & Materials Society.Here we report the growth of molybdenum disulfide (MoS2) films with different thicknesses on silicon dioxide/silicon (SiO2/Si) and c-plane sapphire substrates by sulfurization of direct current (DC) sputtered Mo precursor films in a chemical vapor deposition furnace with sulfur powder at 900°C. The structural, morphological, optical, and electrical properties of the films on different substrates were investigated through a series of characterization in detail. X-ray diffraction (XRD) results showed that the grown films on sapphire substrates had better crystallization and a well-stacked layered structure than the films on SiO2/Si substrates. The frequency difference between the characteristic modes E2g1 and A1g of hexagonal phase MoS2 was determined as ~ 26 cm−1 which is consistent with the typical value of bulk MoS2. Energy-dispersive x-ray (EDX) spectra exhibited that the films were near-stoichiometric. A small shift towards the lower binding energies in the Mo 3d5/2 peak positions was observed due to the valency of Mo below +4 depending on the compositional ratios of the films in x-ray photoelectron spectroscopy (XPS) spectra. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) analysis indicated that the films had smooth surfaces and a well-packed crystal structure. However, when the thickness of the films deposited on sapphire substrates increased, the strain between the sapphire substrate and MoS2 film caused the formation of the micro-domes in the film. In addition, the films exhibited high absorption and reflection properties in the near-infrared (NIR) and mid-infrared (MIR) regions in Fourier transform infrared (FTIR) analysis. Therefore, it is considered that the films can be used for photodetector applications in these regions and infrared shielding coating applications.