Cationic fluoropolymer composite polishing method
View Patent ↗The invention provides a method for polishing or planarizing a substrate of at least one of semiconductor, optical and magnetic substrates. The method includes attaching a polymer-polymer composite polishing pad having a polishing layer to a polishing device. A hydrophilic polymeric matrix forms the polishing layer. Cationic fluoropolymer particles having nitrogen-containing end groups are embedded in the polymeric matrix. A slurry containing anionic particles is applied to the polymer-polymer composite polishing pad and rubbed against the substrate to polish or planarize the substrate with the fluoropolymer particles interacting with the anionic particles to increase polishing removal rate.
1. A method for polishing or planarizing a substrate of at least one of semiconductor, optical and magnetic substrates, the method comprising the following:
attaching a polymer-polymer composite polishing pad to a polishing device, the polymer-polymer polishing pad having a polishing layer, the polishing layer having a polishing surface for polishing or planarizing the substrate, a polymeric matrix forming the polishing layer, the polymer matrix being a first polymer, the first polymer being hydrophilic as measured with distilled water at a pH of 7 at a surface roughness of 10 μm rms after soaking in distilled water for five minutes and the first polymer not being a fluoropolymer, and cationic fluoropolymer particles embedded in the polymeric matrix, the cationic fluoropolymer particles having nitrogen-containing end groups, the nitrogen-containing end groups concentrating at the surface of the cationic fluoropolymer particles, the cationic fluoropolymer particles having a cationic zeta potential as measured in distilled water at a pH of 7;
applying a slurry to the polymer-polymer composite polishing pad, the slurry containing anionic particles; and
rubbing the polymer-polymer composite polishing pad against the substrate to polish or planarize the substrate with the fluoropolymer particles interacting with the anionic particles to increase polishing removal rate of the substrate.
2. The polishing or planarizing method of claim 1 wherein polishing or planarizing occurs with the fluoropolymer particles having a positive zeta potential and the polymer matrix having a negative zeta potential.
3. The polishing or planarizing method of claim 1 wherein the polishing or planarizing occurs with the slurry containing silica particles and at a pH above the isoelectric pH of the silica particles to increase substrate removal rate.
4. The polishing or planarizing method of claim 1 wherein the polishing or planarizing occurs with the slurry containing silica particles and at a pH above the isoelectric pH of the silica particles to decrease polishing defects.
5. The polishing or planarizing method of claim 1 wherein the cationic fluoropolymer particles increase friction between the polymer-polymer composite polishing pad and the substrate to increase substrate removal rate.
6. A method for polishing or planarizing a substrate of at least one of semiconductor, optical and magnetic substrates, the method comprising the following:
attaching a polymer-polymer composite polishing pad to a polishing device, the polymer-polymer polishing pad having a polishing layer, the polishing layer having a polishing surface for polishing or planarizing the substrate, a polymeric matrix forming the polishing layer, the polymer matrix being a first polymer, the first polymer being hydrophilic as measured with distilled water at a pH of 7 at a surface roughness of 10 μm rms after soaking in distilled water for five minutes and the first polymer not being a fluoropolymer, and cationic polyvinylfluoride particles embedded in the polymeric matrix, the cationic polyvinylfluoride particles having nitrogen-containing end groups, the nitrogen-containing end groups concentrating at the surface of the cationic polyvinylfluoride particles, the cationic polyvinylfluoride particles having a cationic zeta potential as measured in distilled water at a pH of 7;
applying a slurry to the polymer-polymer composite polishing pad, the slurry containing anionic particles; and
rubbing the polymer-polymer composite polishing pad against the substrate to polish or planarize the substrate with the polyvinylfluoride particles interacting with the anionic particles to increase polishing removal rate of the substrate.
7. The polishing or planarizing method of claim 6 wherein polishing or planarizing occurs with the polyvinylfluoride particles having a positive zeta potential and the polymer matrix having a negative zeta potential.
8. The polishing or planarizing method of claim 6 wherein the polishing or planarizing occurs with the slurry containing silica particles and at a pH above the isoelectric pH of the silica particles to increase substrate removal rate.
9. The polishing or planarizing method of claim 6 wherein the polishing or planarizing occurs with the slurry containing silica particles and at a pH above the isoelectric pH of the silica particles to decrease polishing defects.
10. The polishing or planarizing method of claim 6 wherein the cationic polyvinylfluoride particles increase friction between the polymer-polymer composite polishing pad and the substrate to increase substrate removal rate.