The effective damage-free megasonic cleaning using N2 dissolved APM

In order to improve yields in the semiconductor manufacturing, it is very important to develop a cleaning process which can remove particles efficiently without damaging the fine structures of the advanced devices. We have found that it was possible to clean wafers efficiently without damage to finely patterned structures by the megasonic cleaning using the conventional APM (ammonia-hydrogen peroxide mixture) into which N₂ gasses were dissolved. It was revealed that the conventional APM can be applied to the advanced processes using this cleaning technology.