Thin layer analysis

 

Investigation of molybdenum disulfide (MoS2) films grown on different substrates

SIMS measurements of the MoS2/substrate interface reveals oxygen out-diffusion from the substrates containing oxygen and the formation of an amorphous MoOS layer in addition to MoS2. The total area of MoS2 (green regions) and amorphous MoOS (blue regions) domains covering the substrate is directly related to the type of substrate. For SiO2, small triangular domains of MoS2 separated by amorphous MoOS material are observed. For Al2O3, the sizes of the MoS2 domains are drastically improved due to the higher stability of sapphire. For a BN substrate, SIMS measurements reveal a uniform MoS2 coverage over the whole 2-inch wafer, which is promising for device fabrication.

Recorded on CAMECA SC Ultra at Institute of Electronic Materials Technology, Warsaw, Poland. Image courtesy of P. Michałowski.
P. Michalowski et al. Destructive role of oxygen in growth of molybdenum disulfide determined by secondary ion mass spectrometry. Phys. Chem. Chem. Phys 21, 8837-8842 (2019)

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