Resist Removal Using Laser Irradiation Combined with Ozone Water Treatment

Laser induced resist stripping technique in water is interesting for both fast and environment-friendly resist removal. However, small pieces of the deposited resist still remain or reattach on the silicon (Si) wafer after laser irradiation. In order to eliminate the remaining resist on the Si wafer surface in environment-friendly way, the effects of ozone water and ozone microbubble water treatments were investigated. The laser induced resist stripping area was effectively expanded by 1.27 times in 600 sec by the immersion treatment in ozone water. Furthermore, combination of ozone microbubbles and flowing water treatment enhanced the resist removal rate by about 20% each. These results demonstrated that the synergy of the laser induced effect, the ozone microbubble and flowing water treatment has a great potential for fast and environment-friendly resist removal technique.