Large-Area Deposition of MoS₂ by Pulsed Laser Deposition with In Situ Thickness Control

Abstract

A scalable and catalyst-free method to deposit stoichiometric molybdenum disulfide (MoS2) films over large areas is reported, with the maximum area limited by the size of the substrate holder. The method allows deposition of MoS2 layers on a wide range of substrates without any additional surface preparation, including single-crystal (sapphire and quartz), polycrystalline (HfO2), and amorphous (SiO2) substrates. The films are deposited using carefully designed MoS2 targets fabricated with excess sulfur and variable MoS2 and sulfur particle size. Uniform and layered MoS2 films as thin as two monolayers, with an electrical resistivity of 1.54 × 10(4) Ω cm(-1), were achieved. The MoS2 stoichiometry was confirmed by high-resolution Rutherford backscattering spectrometry. With the method reported here, in situ graded MoS2 films ranging from ∼1 to 10 monolayers can be deposited.

Dielectric properties and energy‐storage performance of two‐dimensional molybdenum disulfide nanosheets/polyimide composite films

“…As a 2D transition metal dichalcogenide, few‐layer molybdenum disulfide (MoS 2 ) nanosheets have recently attracted considerable interest due to their excellent thermal and mechanical properties, as well as intriguing photocatalytic and electrical properties . These characteristics enable applications such as lubricants, photoactive materials, and film transistors . Moreover, 2D MoS 2 shows great promise as advanced dielectrics considering its appreciable band gap .…”

Atomic Layer Deposition of Crystalline MoS2 Thin Films: New Molybdenum Precursor for Low‐Temperature Film Growth

“…[36][37][38][39] Although upscaling of the sulfurization method appears to be easier compared to the MoO 3 -based CVD, sulfurization tends to produce films of lower quality. [34,36,37] Other bottom-up techniques used for the deposition of thin MoS 2 films include sputtering, [40] physical vapor transport, [41] pulsed laser deposition, [42] and atomic layer deposition (ALD). [43][44][45][46][47][48][49][50][51][52] Atomic layer deposition is an inherently scalable technique that can be regarded as an advanced modification of CVD.…”

Large area few-layer TMD film growths and their applications

“…Lastly, the growth speed is limited only by the pulse rate of the laser, permitting faster growths [48]. Siegel et al [50] grew 2-cm-scale MoS 2 on sapphire, observing that the final layer count of the product was a linear function of the number of laser pulses used to ablate the source MoS 2 powder. In this way, they selectively grew pure monolayer, bilayer, and trilayer films with 50, 100, and 150 pulses respectively [50].…”

“…Siegel et al [50] grew 2-cm-scale MoS 2 on sapphire, observing that the final layer count of the product was a linear function of the number of laser pulses used to ablate the source MoS 2 powder. In this way, they selectively grew pure monolayer, bilayer, and trilayer films with 50, 100, and 150 pulses respectively [50]. This trend stayed consistent all the way to 3000 pulse growths, which produced 60-layer films.…”

“…This trend stayed consistent all the way to 3000 pulse growths, which produced 60-layer films. Growths occurred at 700 • C, with a monolayer being synthesized in a relatively quick 5 min [50]. Serna et al [49] explored the effect of growth temperature, attempting temperatures from 700 • C down to 300 • C. They observed that the stoichiometric ratio of Mo to S suffered at lower temperatures, with S atoms lacking [49].…”