Elimination of BO-LID in mass production using illuminated annealing in a coupled firing and regeneration tool

Elimination of boron-oxygen related degradation (BO-LID) in a coupled fast firing and regeneration belt furnace setup with halogen lamps was investigated. A design of experiment layout was used to systematically change the processing parameters peak firing temperature, belt velocity and illumination intensity in the regeneration tool. The results indicate that a certain threshold illumination intensity is required using typical firing conditions to yield almost complete regeneration. Incomplete regeneration is observed below that threshold intensity. This can be explained by insufficient optical heating and in consequence temperatures too low so that, even though the regeneration process starts as intended, it simply takes too long and is not completed within processing time in the regeneration tool. The results also demonstrate that small variations in firing conditions and precursor quality fluctuations are of minor influence for the regeneration process and that regeneration, for a sufficient illumination setting, can be achieved in a 15 to 30 second timeframe by a regeneration tool based on halogen lamps.