Composition for post chemical-mechanical-polishing cleaning

Abstract

Described is a post chemical-mechanical-polishing (post-CMP) cleaning composition comprising or consisting of: (A) one or more nonionic polymers selected from the group consisting of poly-acrylamides, polyhydroxyethyl(meth)acrylates (PHE(M)A), polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), polymers of formula (I), and mixtures thereof, wherein R1 is hydrogen, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, or sec-butyl, R2 is hydrogen or methyl, and n is an integer, (B) poly(acrylic acid) (PAA) or acrylic acid-maleic acid copolymer with a mass average molar mass (Mw) of up to 10,000 g/mol, and (C) water, wherein the pH of the composition is in the range of from 7.0 to 10.5. ##STR00001##

Claims

1. A post chemical-mechanical-polishing (post-CMP) cleaning composition comprising: (A) one or more nonionic polymers selected from the group consisting of polyacrylamides, polyhydroxyethyl(meth)acrylates (PHE(M)A), polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), polymers of formula (I), and mixtures thereof, ##STR00003## wherein R1 is hydrogen, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, or sec-butyl, R.sub.2 is hydrogen or methyl, and n is an integer, (B) a poly(acrylic acid) (PAA) or acrylic acid-maleic acid copolymer with a mass average molar mass (Mw) of up to 10,000 g/mol, and (C) water, wherein the pH of the composition is in the range of from 7.0 to 10.5, wherein the total amount of the one or more nonionic polymers is in a range of from 0.1 wt. % to 7.5 wt. %, wherein the total amount of the poly(acrylic acid) (PAA) and acrylic acid-maleic acid copolymer is in a range of from 0.1 wt. % to 7.5 wt. %, wherein the post-CMP cleaning composition is capable of removing post-CMP residues without deleteriously affecting of semiconductor integrated circuits.

2. The composition according to claim 1, wherein the pH of the composition is in the range of from 7.5 to 10.

3. The composition according to claim 1, wherein said nonionic polymer (A) is selected from the group consisting of polypropylene oxides (PPO), polypropylene glycols, polyethylene oxides (PEO), and polyethylene glycols (PEG).

4. The composition according to claim 1, wherein said polymer (B) is an acrylic acid-maleic acid copolymer with a mass average molar mass (Mw) of up to 10,000 g/mol.

5. The composition according to claim 1, further comprising (E) one or more defoamers.

6. The composition according to claim 1, further comprising (F) a base.

7. The composition according to claim 1, wherein all constituents of the cleaning composition are in a liquid phase.

8. The composition according to claim 1, wherein the composition is a post chemical-mechanical-polishing (post-CMP) cleaning composition concentrate, comprising: (A) a total amount of the one or more nonionic polymers in a range of from 0.1 to 5.0 wt.-%, based on the total weight of the composition, and (B) a total amount of the poly(acrylic acid) (PAA) and acrylic acid-maleic acid copolymer in a range of from 0.1 to 7.5 wt.-%, based on the total weight of the composition.

9. The composition according to claim 1, further comprising (D) one or more corrosion inhibitors.

10. The composition according to claim 9, wherein the corrosion inhibitors (D) are selected from the group consisting of acetylcysteine, N-acyl-sarcosines, alkylsulfonic acids, alkyl-aryl sulfonic acids, isophthalic acid, alkyl phosphates, polyaspartic acid, imidazole and its derivatives, polyethylenimine with a mass average molar mass (Mw) in the range of from 200 to 2,000 g/mol, derivatives of triazoles, and derivatives of ethylene diamine.

11. A process for the manufacture of a semiconductor device from a semiconductor substrate, comprising removing residues and contaminants from the surface of the semiconductor substrate by contacting it at least once with a composition according to claim 1.

12. The process according to claim 11, further comprising chemical-mechanical-polishing (CMP).

Description

EXAMPLES AND COMPARATIVE EXAMPLES

(1) The invention is hereinafter further illustrated by means of examples and comparison examples.

Examples 1 to 12

Example 1

(2) For the preparation of 20,000 g of a post-CMP cleaning composition concentrate, 14,000 g of pure water with an electrical resistivity of above 18 MO at 25 C. and a total organic carbon (TOC) amount of less than 10 ppb were provided. The water was stirred and 500 g polyethylene glycol (PEG) with a mass average molar mass (Mw) of 1,500 g/mol (Pluriol 1500) were added and the solution was stirred for at least 20 minutes until the polyethylene glycol (PEG) was dissolved. Subsequently, 2,000 g of an aqueous solution (25 wt.-%) of an acrylic acid-maleic acid copolymer (Planapur 12 SEG) were added to the solution and the solution was stirred for further 20 minutes. The pH value of the solution was adjusted to a desired value of 7.5 by adding of an aqueous potassium hydroxide solution (48 wt.-%). The resulting solution was filled up with pure water to an overall weight of 20,000 g.

Examples 2 to 12

(3) The post-CMP cleaning composition concentrates of the examples 2 to 12 were prepared analogously to example 1 by mixing their ingredients. The Table 1 summarizes their compositions.

(4) TABLE-US-00001 TABLE 1 The compositions of the post-CMP cleaning composition concentrate (Balance: Water) etching rate Example constituent constituent constituent constituent [/min] AFM No. (A) (B) (D) (F) pH Co measurement 1 PEG M.sub.w Sokalan CP KOH 7.5 9.5 good 1500; 12 S; 2.5 wt.-% 2.5 wt.-% 2 PEG M.sub.w Sokalan CP Sarkosyl O; KOH 9.0 7.3 good 1500; 12 S; 0.1 wt.-% 2.5 wt.-% 2.5 wt.-% 3 PEG M.sub.w Sokalan CP Sarkosyl O; KOH 7.5 1.6 good 1500; 12 S; 0.75 wt.-% 2.5 wt.-% 2.5 wt.-% Imidazol; 2.5 wt.-% 4 PEG M.sub.w Sokalan CP Imidazol; KOH 7.5 0.0 good 1500; 12 S; 2.5 wt.-%; 2.5 wt.-% 2.5 wt.-% Sarkosyl O: 0.75 wt.-%; Quadrol L: 0.75 wt.-% 5 PVA Sokalan CP Sarkosyl O: 12 S; 0.75 wt.-%; 2.5 wt.-% 6 PAAm Sokalan CP Sarkosyl O: 12 S; 0.75 wt.-%; 2.5 wt.-% 7 PVP Sokalan CP Sarkosyl O: 12 S; 0.75 wt.-%; 2.5 wt.-% 8 PEG/PEO Sokalan CP Sarkosyl O: 12 S; 0.75 wt.-%; 2.5 wt.-% 9 PVA Sokalan CP DBSA 0.75 + 12 S; BTA 2.5 wt.-% 2.5 wt.-% 10 PAAm Sokalan CP DBSA 0.75 + 12 S; BTA 2.5 wt.-% 2.5 wt.-% 11 PVP Sokalan CP DBSA 0.75 + 12 S; BTA 2.5 wt.-% 2.5 wt.-% 12 PEG/PEO Sokalan CP DBSA 0.75 + 12 S; BTA 2.5 wt.-% 2.5 wt.-%

Comparative Examples 1 to 4

(5) The compositions of comparative examples 1 to 4 were prepared analogously to example 1 by mixing their ingredients. The Table 2 summarizes their compositions.

(6) TABLE-US-00002 TABLE 2 The compositions of comparative examples 1 to 4 (Balance: Water) etching Comparative rate Example [/min] AFM No. constituent 1 constituent 2 constituent 3 constituent 4 pH Co measurement 1 KOH 8.5 6.7 bad 2 PEG M.sub.w KOH 8.5 2.9 bad 1500; 2.5 wt.-% 3 Sokalan KOH 8.5 7.5 bad CP 12 S; 2.5 wt.-% 4 Sokalan CaCl.sub.2 KOH 8.5 15 bad CP 12 S; 5 wt.-% 2.5 wt.-%
Atomic Force Microscopy (AFM) Measurements:

(7) For determining cleaning efficiency with Atomic force microscopy (AFM), a 2.52.5 cm Co (deposited on silicon by a chemical vapor deposition process) wafer coupon which was polished with a BTA and colloidal silica containing barrier CMP Slurry was rinsed with ultra-pure water for 10 s, subsequently dipped for 30 s in a beaker with above mentioned cleaning solutions and stirred with a magnetic stirrer for 30 s (300 rpm). After a final rinsing step for 10 s with ultra-pure water, the coupon was dried with nitrogen flow and submitted to an AFM tool (Bruker ICON, Germany) using tapping mode and a 55 m area with appropriate resolution. The results of the AFM measurement were evaluated and the results were classified in the categories good (few particles), medium (some particles), and bad (many particles). The results are shown in table 1 and 2.

(8) The Etching Rates of the Compositions:

(9) The etching rates of the compositions of the examples 1 to 8 and comparative examples 1 to 4 were measured. All coupons were measured before regarding the thickness of the Co layer by using a 4-point probe device as mentioned below. The above mentioned cobalt coupons were pretreated with a 3% citric acid solution for 5 min to remove native oxide. After rinsing with ultra-pure water, the coupon was immersed in above described PCC solutions for 5 minutes using an agitation by a magnetic stirrer (300 rpm). After removing from the etching bath, the coupons were rinsed with deionized water and the thickness was measured with a 4 point probe device supplied by Napson Corporation, Japan (RG2000). The etching rates (in Angstroms per minute) were calculated. The results are shown in table 1 and 2.