Research: Chemical reactions
In material research, chemical reactions such as oxidation, reduction, and wet/dry etching are involved in almost every step of the process. As a noninvasive electrical imaging tool, the MIM is ideal to monitor the spatial evolution of various chemical reactions, which are usually accompanied by large change of dielectric/conductivity properties. The result may shed some light on the synthesis, fabrication, and degradation of functional materials and devices.
J.-S. Kim et al. Sci. Rep. 5, 8989 (2015)
Our results reveal the degradation process of black phosphorus flakes capped by a thin layer of Al2O3. The chemical reaction with ambient moisture and oxygen starts from the poorly covered sample edges. The MIM-Re images, collected daily over one week, nicely demonstrate the edge-initiated conductivity changes.
Y. Liu et al. Nano Lett. 15, 4979 (2015)
The lateral propagation of the thermal oxidation process in WSe2 is vividly shown in our experiment. In this partially oxidized WSe2 flake, the off-stoichiometric WO3-x is highly conductive, as evidenced by the strong MIM signals in the WO3-WSe2 interface.
This research is funded by the Welch Foundation Grant F-1814.