Langmuir-Schaefer deposition of quantum dot multilayers

Application of colloidal nanocrystals in various devices requires their assembly into well-defined mono- or multilayers. We explore the possibilities of the Langmuir-Schaefer technique to make such layers, using CdSe quantum dots as a model system. The layer quality is assessed using Atomic Force Microscopy, Transmission Electron Microscopy and UV-VIS absorption spectroscopy. For hydrophobic substrates, we find that the Langmuir-Schaefer technique is an excellent tool for multilayer production. With hydrophilic substrates, dewetting induces a cellular superstructure. Combination with photolithography leads to micropatterned multilayers, and combination of different nanocrystal sizes allows for the formation of 2D binary superstructures