Synthesis, Characterization, and Modeling of Nitrogen-Passivated Colloidal and Thin Film Silicon Nanocrystals

We review our main experimental and theoretical results on the optical emission properties of Si-nanocrystals (Si-nc´s) fabricated by colloidal and thin film deposition techniques, showing that the surface chemistry of the Si-nc´s or the surrounding matrix play a crucial role in determining both the structural stability and the optoelectronic properties of Si-nc. Our results, guided by first-principles simulations indicate that nitrogen, oxygen, and carbon atoms bonded to the surface of nanometer silicon clusters play a crucial role in the emission mechanism of small Si quantum dots. The control and the understanding of the Si-nc surface structure and composition can provide alternative routes toward the fabrication of optically active complementary metal/oxide semiconductor devices