The energy of a ultraviolet ray laser determines greater or lesser hydrophilicity of the particles in suspension, with consequent different self-assembling modalities of silicon micro-wires
The application potentialities of silicon micro-wires are not completely known, yet, and if these structures might be obtained through repeatable and controllable processes, we would pave the way to technological innovations that are not currently possible with optical fibres, with relatively much bigger sizes. At the Chemical Department of the Sidney University, in Australia, the researchers have recently perfected a new production technique of nano-wires, actually a self-assembling of silicon nano-particles made of micro-wires with high uniformity degree. This process generates revolutionary consequences because it enables, for the first time, the combination of silicon with other materials to implement integrated devices. If we consider glass optical fibres, base for high-speed communication systems on long distances, the silicon of which they are made is generally incompatible with several other materials, so that providing these light guides with additional capabilities, besides the transport of light signals, has always been a difficult challenge. It is worth adding, then, that the combination with typical photonic components, such as optical switches, light sources and also sensors, needs some form of interconnection, and the losses of efficiency at this level are still one of the greatest unsolved problems in optical communications. Silicon micro-wires, if they were able to “self-assemble” on the spot, would have the potential to operate as microscopic optical interconnections: in absence of cladding, unlike optical fibres, we would achieve a bigger light confinement in structures of minimum dimensions and more suitable for the interconnection of devices. The process conceived by Australian researchers just provides for the self-assembling of micro-wires starting from nanoparticles suspended in a solution, where the “solvent” is just water. When the water drops evaporate, they generate some micro-fluidic currents that impose precise configurations to nanoparticles, held together by intermolecular attraction forces. When water evaporates completely, nanoparticles crystallize.
