Claims
- 1. A chemical mechanical polishing method comprising the steps of:
providing a semiconductor wafer including a dielectric layer and a metal layer formed over at least a portion of the dielectric layer; providing at least one polishing pad for chemical mechanical polishing; providing a first slurry mixture for polishing the metal layer and polishing the metal layer, leaving a surface of the dielectric layer exposed; and providing a second slurry mixture for polishing the dielectric layer and polishing layer after the step of polishing the metal layer, wherein the first slurry mixture and second slurry mixture each have a pH in the range of approximately 2 to approximately 4.
- 2. The method of claim 1, wherein a single polishing pad is used for polishing through at least a portion of the metal layer and for polishing the dielectric layer.
- 3. The method of claim 2, wherein the step of polishing the dielectric layer is carried out immediately after the step of polishing the metal layer.
- 4. The method of claim 1, wherein the first slurry includes an oxidizing component and has a pH in the range of 2 to 4.
- 5. The method of claim 1, wherein the first slurry includes water, Fe(NO3)3, and Al2O3.
- 6. The method of claim 1, wherein the first slurry includes a component selected from the group consisting of Fe(NO3)3 and KIO3.
- 7. The method of claim 1, wherein the first slurry includes H2O2.
- 8. The method of claim 4, wherein the second slurry includes an oxide etchant and has a pH in the range of 2-4.
- 9. The method of claim 1, wherein the metal layer is tungsten.
- 10. A method for chemical mechanical polishing a component, the method comprising the steps of:
providing a dielectric layer; forming at least one via through the dielectric layer; forming a tungsten layer within the via and over the dielectric layer; performing a first chemical mechanical polishing step and removing the tungsten layer from over the dielectric layer using a first slurry having an oxidizing component and having a pH of approximately 2 to approximately 4; and performing a second chemical mechanical polishing step and polishing the dielectric layer using a second slurry having a pH in the range of approximately 2 to approximately 4.
- 11. The method of claim 10, wherein the first and second CMP steps are performed on the same polishing pad.
- 12. The method of claim 10, wherein the first and second slurries each have a pH in the range of 2 to 4.
- 13. The method of claim 10, further comprising forming a conducting layer over the dielectric layer after polishing the dielectric layer.
- 14. The method of claim 13, wherein the conducting layer includes a barrier layer and a metal wiring line layer.
- 15. The method of claim 10, wherein the first slurry includes a component selected from the group consisting of Fe(NO3)3 and KIO3.
- 16. A method for forming an integrated circuit structure including chemical mechanical polishing a tungsten layer overlying a dielectric layer, the method comprising:
providing a dielectric layer over a substrate; providing at least one via through the dielectric layer; providing a tungsten plug in the via and a tungsten layer over at least a portion of the dielectric layer; providing a first slurry including abrasive particles and having a pH of approximately 2 to approximately 4; providing a second slurry including abrasive particles and having a pH of approximately 2 to approximately 4; providing a polishing pad on a chemical mechanical polishing apparatus; performing a first chemical mechanical polishing step on the polishing pad using the first slurry to remove the tungsten layer from over the dielectric layer; and performing a second chemical mechanical polishing step on the polishing pad using the second slurry to polish the dielectric layer.
- 17. The method of claim 16, wherein the first slurry is supplied to the polishing pad during the first chemical mechanical polishing step and is not supplied to the polishing pad during the second chemical mechanical polishing step, and wherein the second slurry is supplied to the first polishing pad during the second chemical mechanical polishing step and is not supplied to the polishing pad during the first chemical mechanical polishing step.
- 18. The method of claim 17, wherein the first and second chemical mechanical polishing steps are carried out consecutively.
- 19. The method of claim 16, further comprising depositing a conducting layer over the dielectric layer and on the tungsten plug after the first and second chemical mechanical polishing steps.
- 20. The method of claim 16, wherein the first and second slurries each have a pH of 2 to 4, and further comprising the step of forming a wiring line layer over the dielectric layer and in electrical contact with the tungsten plug.
RELATED PATENT APPLICATION
[0001] This application incorporates by reference U.S. patent application Ser. No. ______, attorney docket no. JIA 480, filed on Nov. 24, 1997, entitled “Chemical Mechanical Polishing Methods Using A Single Slurry Mixture,” by Ming-Sheng Yang, J. Y. Wu, Water Lur, and Shih-Wei Sun.
[0002] This application claims priority from the following provisional applications:
[0003] 1. U.S. patent application Ser. No. ______, attorney docket no. UMC-97-130, filed on Sep. 12, 1997, entitled “Chemical Mechanical Polishing Methods Using Low pH Slurry Mixtures,” by Ming-Sheng Yang, J. Y. Wu, Water Lur, and Shih-Wei Sun.
[0004] 2. U.S. patent application Ser. No. ______, attorney docket no. UMC-97-130, filed on Sep. 30, 1997, entitled “Chemical Mechanical Polishing Methods Using Low pH Slurry Mixtures,” by Ming-Sheng Yang, J. Y. Wu, Water Lur, and Shih-Wei Sun.
[0005] 3. U.S. patent application Ser. No. ______, attorney docket no. UMC-97-131, filed on Sep. 12, 1997, entitled “Chemical Mechanical Polishing Methods Using A Single Slurry Mixture,” by Ming-Sheng Yang, J. Y. Wu, Water Lur, and Shih-Wei Sun.
[0006] 4. U.S. patent application Ser. No. ______, attorney docket no. UMC-97-131, filed on Sep. 30, 1997, entitled “Chemical Mechanical Polishing Methods Using A Single Slurry Mixture,” by Ming-Sheng Yang, J. Y. Wu, Water Lur, and Shih-Wei Sun.