Subcategory: Materials Science
Sebastian O. Manzo - Pennsylvania State University
Co-Author(s): Maxwell T. Wetherington and Dr. Joshua A. Robinson
Two-dimensional (2D) molybdenum disulfide has unique mechanical, electrical and optical properties, making it a prime candidate for nanoelectronic and optoelectronic applications. Thermal management is a critical aspect of device performance. In fact, it has become a limiting factor for further minimization of modern electronics. Consequently, finding an experimental method that can efficiently and consistently characterize the thermal properties of MoS2 is crucial, which is the focus of this project. By using luminescence nanothermometry on supported and suspended MoS2 flakes, a correlation between its luminescence properties, temperature and laser power can be established. This data can then be used to calculate the thermal conductivity and the interfacial heat transport of MoS2. Although Raman thermometry is more commonly used, it has been shown to have high measurement uncertainty. This is confirmed by the results of this study, which demonstrated that the Raman measurements were inconsistent and the data difficult to process. On the other hand, a clear and constant trend between the photoluminescence (PL) of supported MoS2 and temperature was established on both SiO2/Si and sapphire substrates. The relationship between the PL and the laser power was more difficult to determine, varying significantly between different flakes. The reason behind this has not yet been established, although a possible explanation could be the influence of the thermal contact resistance between the MoS2 and the substrate on the measurements. In order to abate its effects, one- and two-laser luminescence thermometry on suspended flakes should also be conducted.
Funder Acknowledgement(s): This study could not have been accomplished without the support of the National Science Foundation grant for the Emerging Frontiers in Research and Innovation (EFRI) for Two-Dimensional Atomic Layer Research and Engineering (2-DARE).
Faculty Advisor: Dr. Joshua A. Robinson, email@example.com
Role: Although I received extensive guidance and advice from my research mentor and adviser, I conducted the experiments associated with this project independently. I want to also acknowledge the staff scientists of the Millennium Science Complex at the Pennsylvania State University who trained me on a variety of devices. Lastly, this research would not have been possible without the MoS2 samples that were grown and provided for me by other members of the J.A. Robinson Research Group.