Thermal boundary conductance of CVD-grown MoS2 monolayer-on-silica substrate determined by scanning thermal microscopy

Abstract

We characterize heat dissipation of supported molybdenum disulfide (MoS2) monolayers grown by chemical vapor deposition by means of ambient-condition scanning thermal microscopy (SThM). We find that the thermal boundary conductance of the MoS2 monolayers in contact with 300 nm of SiO2 is around 4.6 ± 2 MW m−2 K−1. This value is in the low range of the values determined for exfoliated flakes with other techniques such as Raman thermometry, which span an order of magnitude (0.44–50 MW m−2 K−1), and underlines the dispersion of measurements. The sensitivity to the in-plane thermal conductivity of supported MoS2 is very low, highlighting that the thermal boundary conductance is the key driver of heat dissipation for the MoS2 monolayer when it is not suspended. In addition, this work also demonstrates that SThM calibration using different thicknesses of SiO2, initially aimed at being used with bulk materials can be extended to 2D materials.