Activation of Si-N Modes in Silicon by Pulsed Laser
Annealing
ABSTRACTRetention and bonding of nitrogen implanted into crystalline Si were examined by infrared absorption (ir) and transmission electron microscopy (TEM) after furnace and pulsed laser annealing. Localized Si-N vibrational modes for N-N pairs are observed, and the associated ir band intensities increase upon pulsed annealing. Furnace annealing above 600°C decreases the ir intensity for N-N pairs and fine structure defects appear in TEM. Subsequent laser annealing removes most of the fine structure and reactivates the pair spectrum which we interpret as dissolution of N precipitates and pair formation upon quenching from the melt. Any realistic model for N in Si must include the formation and consequences of N-N pairs.