Copper electrodeposition in microelectronics
A method and composition for electroplating Cu onto a substrate in the manufacture of a microelectronic device involving and electrolytic solution containing a source of Cu ions and a quaternized pyridinium salt compound for leveling.
1. A method for electroplating Cu onto a substrate having electrical interconnect features in the manufacture of a microelectronic device, the method comprising:
immersing the substrate in an electrolytic solution comprising the following:
a source of Cu ions;
one or more superfilling agent compounds which promote a Cu deposit characterized by a rate of growth in the vertical direction which is substantially greater than a rate of growth in the horizontal direction, wherein the superfilling agent compounds comprise an accelerator and a suppressor, and
a leveling agent comprising a quaternized pyridyl polymer compound comprising a polymer of 4-vinyl pyridine; and
supplying electrical current to the electrolytic solution to deposit Cu onto the substrate.
2. The method of claim 1 wherein said polymer of 4-vinyl pyridine is a 4-vinyl pyridine homo-polymer.
3. The method of claim 1 wherein said polymer of 4-vinyl pyridine is a 4-vinyl pyridine co-polymer.
4. The method of claim 1 wherein said polymer of 4-vinyl pyridine is a reaction product of 4-vinyl pyridine.
5. The method of claim 1 wherein said polymer of 4-vinyl pyridine is a reaction product of poly(4-vinyl pyridine).
6. The method of claim 1 wherein said polymer of 4-vinyl pyridine is a reaction product of 4-vinyl pyridine and methyl sulfate.
7. The method of claim 1 wherein said polymer of 4-vinyl pyridine is a reaction product of poly(4-vinyl pyridine) and methyl sulfate.
8. The method of claim 1 wherein said 4-vinyl pyridine polymer is prepared by a process that comprises a reaction between 4-vinyl pyridine and a compound of formula 1:
R 1 -L (1)
wherein R 1 is alkyl, alkenyl, aralkyl, heteroarylalkyl, substituted alkyl, substituted alkenyl, substituted aralkyl or substituted heteroarylalkyl; and
L is a leaving group.
9. The method of claim 1 wherein said 4-vinyl pyridine polymer is prepared by a process that comprises reacting poly(4-vinyl pyridine) with dimethyl sulfate, reacting poly(4-vinyl pyridine) with methyl tosylate, reacting 4-vinyl pyridine with dimethyl sulfate, reacting 4-vinyl pyridine with methyl tosylate, reacting 4-vinyl pyridine with 2-chloroethanol, reacting 4-vinyl pyridine with benzylchloride, reacting 4-vinyl pyridine with allyl chloride, reacting 4-vinyl pyridine with 4-chloromethylpyridine, reacting 4-vinyl pyridine with 1,3-propane sultone, reacting 4-vinyl pyridine with methyl tosylate, reacting 4-vinyl pyridine with chloroacetone, reacting 4-vinyl pyridine with 2-methoxyethoxymethylchloride, or reacting 4-vinyl pyridine with 2-chloroethylether.
10. The method as set forth in claim 1 wherein said quaternized polymer of 4-vinyl pyridine comprises a quaternary pyridinium salt, the preparation of which comprises reaction of 4-vinyl pyridine or a polymer comprising repeating units of 4-vinyl pyridine with a compound selected from the group consisting of dimethyl sulfate, methyl tosylate, dimethyl sulfate, methyl tosylate, 2-chloroethanol, benzyl chloride, allyl chloride, chloromethylpyridine, 1,3-propane sultone, chloroacetone, methoxyethoxymethylchloride, 2-chloroethylether, poly(2-methyl-5-vinyl pyridine), and 1-methyl-4-vinylpyridinium trifluoromethyl sulfonate.
11. The method as set forth in claim 10 wherein said 4-vinyl pyridine polymer is prepared by a process comprising reaction of 4-vinyl pyridine monomer or a polymer comprising 4-vinyl pyridine repeating units with dimethyl sulfate or methyl tosylate.
12. The method as set forth in claim 1 wherein:
said leveling agent comprising a quaternized pyridyl polymer compound comprising a 4-vinyl pyridine polymer which has a leveling effect without substantially interfering with superfilling, wherein 4-vinyl pyridine repeating units of said 4-vinyl pyridine polymer have been quaternized with a quaternizing agent selected from the group consisting of dimethyl sulfate, methyl tosylate, 2-chloroethanol, benzyl chloride, allyl chloride, chloroacetone, 2-methoxyethoxymethylchloride, 2-chloroethylether, 1,3-dichloropropanol, alkyl octyl sulfate, and alkyl trifluoromethane sulfonate.
13. The method as set forth in claim 12 wherein said quaternizing agent is selected from the group consisting of dimethyl sulfate, methyl tosylate, chloroacetone, 2-chloroethylether, and 1,3-dichloropropanol.