Chemical mechanical polishing method using slurry composition containing N-oxide compound
View Patent ↗The present disclosure relates to a chemical mechanical polishing (CMP) slurry composition that provides for a high metal to dielectric material selectivity along with a low rate of metal recess formation. In some embodiments, the disclosed slurry composition has an oxidant and an etching inhibitor. The oxidant has a compound with one or more oxygen molecules. The etching inhibitor has a nitrogen-oxide compound. The etching inhibitor reduces the rate of metal and dielectric material (e.g., oxide) removal, but does so in a manner that reduces the rate of dielectric material removal by a larger amount, so as to provide the slurry composition with a high metal (e.g., germanium) to dielectric material removal selectivity and with a low rate of metal recess formation.
1. A chemical mechanical polishing (CMP) slurry composition configured to provide for a high metal to dielectric material removal selectivity with a low rate of metal recess formation, consisting of:
an oxidant comprising a peroxide;
an etching inhibitor configured to reduce a removal rate of a metal relative to an oxide, so as to provide the CMP slurry composition with a metal-to-oxide etching selectivity of greater than or equal to approximately 60-to-1, wherein the etching inhibitor comprises a nitrogen-oxide compound having a chemical formula of R1R2R3N + —O − , wherein N + comprises a nitrogen molecule, O − comprises an oxygen molecule, R1 is a first substituent, R2 is a second substituent, and R3 is a third substituent;
a solvent; and
one or more abrasive particles.
2. The slurry composition of claim 1 , wherein the etching inhibitor comprises 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO) and is configured to reduce a removal rate of silicon germanium relative to a removal rate of an oxide.
3. The slurry composition of claim 1 , wherein the oxidant comprises a concentration having a range of between approximately 10 ppm and 50,000 ppm.
4. The slurry composition of claim 1 ,
wherein the first substituent, R1, and the second substituent, R2, have 1-20 carbon alkyl substituents disposed as cyclic substituents; and
wherein the third substituent, R3, has 0-10 carbon alkyl substituents disposed as cyclic substituents.
5. The slurry composition of claim 1 , wherein the etching inhibitor comprises pyridine N-oxide, 4-methylpyridine N-oxide, N-methylmorpholine N-oxide, 5,5-dimethyl-1-pyrroline N-oxide, trimethylamine N-oxide, quinoline N-oxide, or 2-mercaptopyridine N-oxide.
6. The slurry composition of claim 1 , wherein the etching inhibitor comprises a concentration having a range of between approximately 10 ppm and 50,000 ppm.
7. The slurry composition of claim 1 , further comprising an abrasive including colloidal silica, fumed silica, aluminum oxide, or a silica shell based composite submicron particle.
8. The slurry composition of claim 1 , wherein slurry composition comprises a pH level having a range of between approximately 1 and 10.
9. The slurry composition of claim 1 , further comprising:
a surfactant comprising having a concentration in a range of between approximately 200 ppm and approximately 500 ppm.
10. The slurry composition of claim 9 , wherein the oxidant is ammonium peroxydisulfate, the etching inhibitor is 4-methylptridine N-oxide, and the surfactant is polyethylene glycol.
11. The slurry composition of claim 9 , wherein the oxidant is tetr-butyl hydrogen peroxide, the etching inhibitor is N-methylmorpholine N-oxide, and the surfactant is polyethylene glycol.
12. The slurry composition of claim 11 , wherein the slurry composition is devoid of abrasive particles.
13. A chemical mechanical polishing (CMP) slurry composition, consisting of:
an oxidant comprising potassium peroxydisulfate, ammonium peroxydisulfate, sodium peroxydisulfate, potassium peroxymonosulfate, peracetic acid, or tert-butyl hydrogen peroxide;
an etching inhibitor configured to reduce a removal rate of silicon germanium relative to an oxide, wherein the etching inhibitor consists of pyridine N-oxide, 4-methylpyridine N-oxide, N-methylmorpholine N-oxide, 5,5-dimethyl-1-pyrroline N-oxide, trimethylamine N-oxide, quinoline N-oxide, or 2-mercaptopyridine N-oxide; and
de-ionized water.
14. The slurry composition of claim 13 , further comprising:
a surfactant comprising having a concentration of between approximately 200 and 500 ppm.
15. The slurry composition of claim 14 , wherein the oxidant is ammonium peroxydisulfate, the etching inhibitor is 4-methylptridine N-oxide, and the surfactant is polyethylene glycol.
16. The slurry composition of claim 14 , wherein the oxidant is tetr-butyl hydrogen peroxide, the etching inhibitor is N-methylmorpholine N-oxide, and the surfactant is polyethylene glycol.
17. The slurry composition of claim 16 , wherein the slurry composition is devoid of abrasive particles.
18. The slurry composition of claim 13 , wherein the etching inhibitor comprises a concentration having a range of between approximately 10 ppm and 50,000 ppm.
19. The slurry composition of claim 13 , further comprising an abrasive including one or more of: colloidal silica, fumed silica, aluminum oxide, and a silica shell based composite submicron particle.
20. A chemical mechanical polishing (CMP) slurry composition configured to provide for a high metal to dielectric material removal selectivity with a low rate of metal recess formation, consisting of:
an oxidant comprising a compound having one or more oxygen molecules; and
an etching inhibitor configured to reduce a removal rate of silicon germanium relative to an oxide, wherein the etching inhibitor consists of pyridine N-oxide, 4-methylpyridine N-oxide, N-methylmorpholine N-oxide, 5,5-dimethyl-1-pyrroline N-oxide, trimethylamine N-oxide, quinoline N-oxide, or 2-mercaptopyridine N-oxide;
de-ionized water; and
one or more abrasive particles.