Silicon Nanocrystals Shine For All to See

Here's an interesting story for all the chip heads in the crowd - not to mention a story that is remarkably resistant to a smart-aleck lead-in. SI Diamond Technology has managed to develop a method to produce highly crystalline passivated silicon (Si) nanocrystals, which is good news if you need the things. For a little background, small crystals of semiconductors, in the range of 2 to 50 nanometers, are termed nanocrystals or quantum dots and have different optical properties from the bulk (solid) material. As more atoms are added to the nanocrystal particles and as they grow in size, the properties of these nanocrystals approach the bulk values. In particular, the "band gap" that defines the optical and electronic properties of these materials changes with size. As a result, silicon nanocrystals exhibit a significant blue shift in optical properties from the bulk infrared band gap energy to the visible range. The band gap of the nanocrystals varies with the size of the nanoparticle, so the fluorescent wavelength can be tuned by the size of the nanocrystals. SIDT developed silicon nanoclusters that show efficient blue and green photo-luminescence with very high quantum yields (high efficiency) at room temperature. What can they be used for? Well, some folks say that the glowing nanoclusters could lead to new materials for displays, optical memory, micro-opto-electronic applications, or even fluorescent tags for biological systems. Biological tags could be accomplished by attaching the nanocrystal to a protein, which would transport the tag to a specific cell structure, lighting up your liver or other giblets.