Fluopolymer composite CMP polishing method
The invention provides a method for polishing or planarizing a substrate. First, the method comprises attaching a polymer-polymer composite polishing pad to a polishing device. The polishing pad has a polymer matrix and fluoropolymer particles embedded in the polymeric matrix. The fluoropolymer particles have a zeta potential more negative than the polymeric matrix. Cationic particle-containing slurry is applied to the polishing pad. Conditioning the polymer-polymer composite polishing pad exposes the fluoropolymer particles to the polishing surface and creates fluoropolymer-containing debris particles in the slurry. Polishing or planarizing the substrate with the increased electronegativity from the fluoropolymer at the polishing surface and in the fluoropolymer-containing debris particles stabilizes the cationic particle-containing slurry to decreases the precipitation rate of the cationic particle-containing slurry.
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 composite polishing pad comprising a polishing layer having a polishing surface for polishing or planarizing the substrate, a polymeric matrix forming the polishing layer, the polymer matrix having a tensile strength, and fluoropolymer particles embedded in the polymeric matrix, the fluoropolymer particles having a tensile strength lower than the tensile strength of the polymeric matrix and the fluoropolymer particles having a zeta potential more negative than the polymeric matrix at a pH of 7;
applying a cationic particle-containing slurry to the polymer-polymer composite polishing pad;
conditioning the polymer-polymer composite polishing pad to expose the fluoropolymer particles to the polishing surface and to create fluoropolymer-containing debris particles in the slurry; and
polishing or planarizing the substrate with the increased electronegativity from fluoropolymer at the polishing surface and in the fluoropolymer-containing debris particles stabilizing the cationic particle-containing slurry to decrease precipitation rate of the cationic particle-containing slurry.
2. The polishing or planarizing method of claim 1 wherein the fluoropolymer particles have a settling sensitivity in the slurry containing cationic particles as follows:
a) determine settling slope in (%/hour) for the slurry;
b) determine settling slope in (%/hour) for the slurry plus 0.1 wt % fluoropolymer particles; and
c) slope a)-slope b) being≥5%/hour.
3. The polishing or planarizing method of claim 1 wherein the polishing or planarizing occurs with the slurry containing ceria particles and at a pH below the isoelectric pH of the ceria 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 ceria particles and at a pH below the isoelectric pH of the ceria particles to decrease polishing defects.
5. The polishing or planarizing method of claim 1 wherein the polishing or planarizing occurs with a cationic slurry where the embedded 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 composite polishing pad comprising a polishing layer having a polishing surface for polishing or planarizing the substrate, a polymeric matrix forming the polishing layer, the polymer matrix having a tensile strength, and fluoropolymer particles embedded in the polymeric matrix, the fluoropolymer particles having a tensile strength lower than the tensile strength of the polymeric matrix and the fluoropolymer particles having a zeta potential more negative than the polymeric matrix at a pH of 7;
applying a ceria particle-containing slurry to the polymer-polymer composite polishing pad;
conditioning the polymer-polymer composite polishing pad to expose the fluoropolymer particles to the polishing surface and to create fluoropolymer-containing debris particles in the slurry; and
polishing or planarizing the substrate with the increased electronegativity from fluoropolymer at the polishing surface and in the fluoropolymer-containing debris particles stabilizing the cationic particle-containing slurry to decrease precipitation rate of the ceria particle-containing slurry.
7. The polishing or planarizing method of claim 6 wherein the fluoropolymer particles have a settling sensitivity in the slurry containing cationic particles as follows:
a) determine settling slope in (%/hour) for the slurry;
b) determine settling slope in (%/hour) for the slurry plus 0.1 wt % fluoropolymer particles; and
c) slope a)-slope b) being≥5%/hour.
8. The polishing or planarizing method of claim 6 wherein the polishing or planarizing occurs with the slurry containing ceria particles and at a pH below the isoelectric pH of the ceria 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 ceria particles and at a pH below the isoelectric pH of the ceria particles to decrease polishing defects.
10. The polishing or planarizing method of claim 6 wherein the polishing or planarizing occurs with a cationic slurry where the embedded fluoropolymer particles increase friction between the polymer-polymer composite polishing pad and the substrate to increase substrate removal rate.