Papers by Keyword: Resist Stripping

Abstract: A large amount of chemicals and ultrapure water (UPW) have been used for wet cleaning process in the semiconductor manufacturing processes. One of the most commonly used cleaning solutions is Sulfuric acid (H₂SO₄) and Hydrogen Peroxide (H₂O₂) Mixture (SPM). It is used for resist stripping, etc. on a silicon wafer. As the cleaning process increases, so does the amount of chemicals used with the recent miniaturization. As a result, wastewater will also increase, and there are concerns about the impact on the environmental aspects. The technologies to reduce H₂SO₄ [1, 2] have been developed, but its consumption still persists. Therefore, in this paper, we developed high concentrated O₃-water without using H₂SO₄, and conducted a resist stripping test verify its effectiveness as an alternative to SPM.

Abstract: It is well-known that ion-implant doses greater than 5E14 atoms/cm2 can create an amorphous carbon-like layer “crust”, and also that this crust is extremely difficult to dissolve with wet chemicals. In practice, a combination of dry plasma ashing and wet chemical removal is used to eliminate the photoresist. In this study, a novel photoresist stripping technique is proposed. We have improved wet vapor photoresist stripping technique [1] using the mixture of high-speed steam flow and purified water droplets. Relatively low pressure clean steam is mixed with purified water in the nozzle, and sprayed on a photoresist coated Si wafer. We have also developed a pre-treatment method in a chamber with keeping both temperature and humidity constant, in order to strip post ion-implanted photoresit. The most significant feature of this proposed technique is that we use water only; hence we are able to strip photoresist without chemicals.