Polydimethylsiloxane (PDMS) is a soft and transparent polymer widely used in preparing large scale atomically-thin 2D materials. During the fabrication of 2D heterostructures, it’s crucial to minimize the PDMS residue in each step to ensure optimum interfaces. This work demonstrates that diisopropylamine (DIPA) can effectively remove the PDMS residue from the atomically-thin transition metal dichalcogenides (TMDs). Followed by mild thermal annealing in the argon atmosphere at 150 C, we show the sample quality can be further improved by employing photoluminescence spectroscopy. Last, we demonstrate high-quality 2D-TMD heterostructures made with this method. We observe a clear interlayer exciton emission at room temperature, indicating a great condition of the interfaces.About the speaker
Dr Shao-Yu Chen is a research fellow working with Prof Michael Fuhrer at Monash University to realising Bose-Einstein Condensation of tightly bound excitons in 2D semiconductors. He has extensive research experiences on transport and optical measurement on 2D materials including graphene and transition metal dichalcogenides (TMDs). In particular, he has investigated strong Coulomb interaction and many-body correlation in atomically-thin electronic systems through luminescence and Raman scattering measurements. Shao-Yu works within FLEET’s Research theme 2: exciton superfluids and Enabling technologies A (atomically-thin materials) and B (nano-device fabrication).