Slurry compositions for chemical mechanical planarization
The method includes receiving a semiconductor device having a first surface and a second surface. The first surface is a top surface including a conductive material exposed thereon; and the second surface is an embedded surface including the conductive material and a dielectric material. The method also includes selecting a first polishing slurry to achieve a first polishing rate of the conductive material in the first polishing slurry and a second polishing rate of the dielectric material in the first polishing slurry. The method further includes selecting a second polishing slurry to achieve a third polishing rate of the conductive material in the second polishing slurry and a fourth polishing rate of the dielectric material in the second polishing slurry. The method additionally includes polishing the first surface with the first polishing slurry until the second surface is exposed; and polishing the second surface with the second polishing slurry.
1. A method, comprising:
receiving a semiconductor substrate having a metal material of ruthenium (Ru) exposed on a first surface, the first surface having a uniform material composition of the metal material;
receiving a first slurry including a first abrasive component of titanium oxide and a first amine-based alkaline component of ammonium hydroxide;
polishing the exposed metal material on the first surface with the first slurry until a second surface is exposed, the second surface including the metal material and a dielectric material, wherein the metal material has a first polishing rate and the dielectric material has a second polishing rate;
receiving a second slurry including a second abrasive component of silicon oxide, a second amine-based alkaline component of hydroxyamine, and a non-amine alkaline component; and
polishing the metal material and the dielectric material exposed on the second surface with the second slurry.
2. The method of claim 1 , wherein the semiconductor substrate includes a metal gate structure, and the metal material exposed on the first surface is electrically coupled to the metal gate structure.
3. The method of claim 1 , wherein the second amine-based alkaline component includes a hydroxyamine (H 2 N—R—OH), where R is an organic residue having a substituted alkyl group with a carbon chain of 1 to 20 carbon atoms.
4. The method of claim 1 , further comprising adjusting an ionic strength of the first slurry to a value of about 1 mmol/L to about 500 mmol/L.
5. The method of claim 1 , wherein the receiving of the semiconductor substrate includes receiving the semiconductor substrate having the metal material in a contact feature and in a via feature connected to the contact feature and having silicon oxide in an interlayer dielectric (ILD) component surrounding the via feature and below the contact feature.
6. The method of claim 1 , wherein a zeta potential of the first surface is about-60 mV to about-20 mV.
7. A method, comprising:
receiving a semiconductor device having a first surface and a second surface, the first surface being a top surface including a first conductive feature of ruthenium (Ru) exposed thereon, the first surface having a uniform material composition of Ru, and the second surface including a second conductive feature of Ru and a dielectric material;
selecting a first polishing slurry including a first abrasive component of titanium oxide and a first amine-based alkaline component of ammonium hydroxide;
selecting a second polishing slurry to achieve a first polishing rate of Ru in the second polishing slurry and a second polishing rate of the dielectric material in the second polishing slurry, wherein the second polishing slurry includes a second abrasive component of silicon oxide, a second amine-based alkaline component of hydroxyamine, and a non-amine alkaline component;
polishing the first surface with the first polishing slurry until the second surface is exposed; and
polishing the second surface with the second polishing slurry.
8. The method of claim 7 , wherein the first conductive feature is a contact feature, the second conductive feature is a via feature, and the second conductive feature is embedded within an interlayer dielectric layer (ILD) having the dielectric material.
9. The method of claim 7 , wherein the dielectric material includes silicon oxide.
10. The method of claim 7 ,
wherein the polishing of the first surface includes polishing the first conductive feature, and
wherein the polishing of the second surface includes polishing the second conductive feature and the dielectric material.
11. The method of claim 7 , wherein the selecting of the second polishing slurry includes selecting in order to minimize a difference between the first polishing rate and the second polishing rate.
12. The method of claim 7 , wherein the selecting of the first polishing slurry includes selecting a first acid component having nitric acid, and wherein the selecting of the second polishing slurry includes selecting a second acid component having acetic acid.
13. The method of claim 7 , wherein the second amine-based alkaline component includes a hydroxyamine (H 2 N—R—OH), where R is an organic residue having a substituted alkyl group with a carbon chain of 1 to 20 carbon atoms.
14. A method, comprising:
receiving a semiconductor device having a first surface and a second surface, the first surface being a top surface including a metal material of ruthenium (Ru) exposed thereon, the first surface having a uniform material composition of the metal material, and the second surface being an embedded surface including the metal material and a dielectric material;
selecting a first oxidizing component of a first slurry composition for a first polishing process of the first surface and a second oxidizing component of a second slurry composition for a second polishing process of the second surface, the first oxidizing component oxidizes the metal material into a first oxidation product and the second oxidizing component oxidizes the metal material into a second oxidation product;
selecting a first pH value of the first slurry composition based in part on the first oxidation product and a second pH value of the second slurry composition based in part on the second oxidation product;
selecting a first alkaline component of the first slurry composition to adjust a removal rate of the metal material and a second alkaline component of the second slurry composition;
selecting a first amount of a first abrasive component of the first slurry composition based in part on a hardness of the first abrasive component and a hardness of the first oxidation product, and a second amount of a second abrasive component of the second slurry composition based in part on a hardness of the second abrasive component and a hardness of the dielectric material;
polishing the first surface using the first slurry composition; and
polishing the second surface using the second slurry composition,
wherein the first oxidizing component differs from the second oxidizing component, the first alkaline component differs from the second alkaline component, the first abrasive component differs from the second abrasive component, and wherein the selecting of the second amount of the second abrasive component includes making a ratio of a first removal rate of the dielectric material in the second slurry composition to a second removal rate of the metal material in the second slurry composition to be about 1:0.5 to about 1:2.
15. The method of claim 14 , wherein the second alkaline component includes a hydroxyamine (H 2 N—R—OH), where R is an organic residue having a substituted alkyl group with a carbon chain of 1 to 20 carbon atoms.
16. The method of claim 14 , wherein the selecting of the first oxidizing component, the first pH value, the first alkaline component, and the first amount of the first abrasive component includes selecting to maximize a removal rate of the metal material in the first slurry composition.
17. The method of claim 14 , wherein a ratio of a third removal rate of the dielectric material in the first slurry composition to a fourth removal rate of the metal material in the first slurry composition is less than 1:30.
18. The method of claim 14 , wherein the dielectric material includes silicon dioxide (SiO 2 ).
19. The method of claim 14 , further comprising selecting a first acid of the first slurry composition and a second acid of the second slurry composition, the first acid being different from the second acid.
20. The method of claim 14 , wherein polishing of the first surface using the first slurry composition includes forming anion forms of Ru including [RuO 4 ] 2− , [RuO 4 ] − , or a combination thereof.