Slurry composition for chemical mechanical polishing of Ge-based materials and devices

1. A method, comprising: providing a substrate including a germanium-containing region and an oxide region, wherein the germanium-containing region and the oxide region share a common interface; rotating a chemical mechanical polishing (CMP) platen including a polishing pad disposed thereon; providing a slurry containing an oxidant including a first compound, a germanium removal rate enhancer including a second compound comprising at least one methyl group, and an abrasive onto a surface of the polishing pad during the rotating; and contacting the polishing pad having the slurry thereon to the common interface of the germanium-containing region and the oxide region.

2. The method of claim 1 , further comprising:

after contacting the rotating polishing pad to the common interface, polishing the common interface, wherein the polishing is configured to remove material from the germanium-containing region at a higher rate than from the oxide region, and wherein the common interface of the germanium-containing region and the oxide region is substantially flat after polishing.

3. The method of claim 1 , wherein the germanium removal rate enhancer includes at least one of 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 2,3-dimethylpyridine, 2,4-dimethylpyridine, 2,6-dimethylpyridine, and 3,5-dimethylpyridine.

4. The method of claim 3 , wherein the oxidant includes one or more of hydrogen peroxide, potassium peroxodisulfate, ammonium peroxodisulfate, sodium peroxodisulfate, potassium peroxymonosulfate, peracetic acid, and tert-butyl hydrogen peroxide.

5. The method of claim 1 , wherein the providing the slurry further includes providing at least one of an etching inhibitor, a surfactant, an organic complexant, a chelating agent, an organic or inorganic acid, an organic or inorganic base, a corrosion inhibitor, and a buffer.

6. A method, comprising:

providing a substrate including a germanium-containing region and a second region, wherein the germanium-containing region and the second region share a common interface;

rotating a chemical mechanical polishing (CMP) platen including a polishing pad disposed thereon;

providing a slurry containing a germanium removal rate enhancer onto a surface of the polishing pad during the rotating, the germanium removal rate enhancer including at least one of a methylpyridine compound and a methylpyridine derivative compound; and

contacting the polishing pad having the slurry thereon to the common interface of the germanium-containing region and the oxide region.

7. The method of claim 6 wherein the second region is an oxygen-containing region, the slurry further containing an oxidant having one or more oxygen atoms.

8. The method of claim 7 wherein comprising:

providing an abrasive including at least one of colloidal silica, fumed silica, aluminum oxide, silica shell based composite submicron particles, and ceria, to the slurry.

9. The method of claim 7 further comprising

providing at least one of a surfactant, an organic complexant, a chelating agent, an organic or inorganic acid, an organic or inorganic base, a corrosion inhibitor, and a buffer to the slurry.

10. The method of claim 7 wherein the slurry composition includes a slurry composition having a pH level in a range of between approximately 1 and 6.

11. The method of claim 7 wherein the oxidant includes one or more of hydrogen peroxide, potassium peroxodisulfate, ammonium peroxodisulfate, sodium peroxodisulfate, potassium peroxymonosulfate, peracetic acid, and tert-butyl hydrogen peroxide.

12. The method of claim 7 wherein the oxidant includes an oxidant concentration between approximately 10 ppm and 50,000 ppm.

13. The method of claim 6 wherein the germanium removal rate enhancer includes the methylpyridine compound including at least one of 2-methylpyridine, 3-methylpyridine, and 4-methylpyridine.

14. The method of claim 6 wherein, wherein the germanium removal rate enhancer includes the methylpyridine derivative compound including at least one of 2,3-dimethylpyridine, 2,4-dimethylpyridine, 2,6-dimethylpyridine, and 3,5-dimethylpyridine.

15. The method of claim 6 wherein the germanium removal rate enhancer includes a germanium removal rate enhancer concentration between approximately 100 ppm and 5,000 ppm.

16. The method of claim 6 further comprising:

providing an etching inhibitor to the slurry.

17. The method of claim 16 wherein the etching inhibitor includes 2-mercaptopyridine N-oxide.

18. The method of claim 16 wherein the etching inhibitor includes an etching inhibitor concentration of between approximately 100 ppm and 5,000 ppm.

19. A method for chemical mechanical polishing (CMP) a workpiece, comprising:

distributing a slurry having a slurry composition including an oxidant and a germanium removal rate enhancer, wherein the germanium removal rate enhancer includes at least one of a methylpyridine compound and a methylpyridine derivative compound; and

rotating a polishing pad disposed on a platen relative to a substrate, wherein the slurry is distributed onto a surface of the polishing pad; and

positioning the workpiece adjacent with the polishing pad.

20. The method of claim 19 , wherein the germanium removal rate enhancer includes the methylpyridine compound including at least one of 2-methylpyridine, 3-methylpyridine, and 4-methylpyridine.