Intense violet and blue light emission from Si nanowires fabricated via solid–liquid–solid growth from amorphous Si films

Violet and blue luminescent Si nanowires were fabricated by annealing an amorphous Si film on a Ni-coated Si substrate via solid–liquid–solid growth. The fabricated Si nanowires have an average diameter of 50 nm. The wire stem is composed of a crystalline Si core of several nanometers and an amorphous oxide sheath. The Si nanowires are capable of emitting strong violet and blue luminescence in the spectral region ranging from 380 to 500 nm, which has a very short decay time of tens of nanoseconds, and is remarkably different in spectral region and luminescence time from the luminescence emitted by Si nanocrystals.