Method of electroplating photoresist defined features from copper electroplating baths containing reaction products of pyrazole compounds and bisepoxides
Electroplating methods enable the plating of photoresist defined features which have substantially uniform morphology. The electroplating methods include copper electroplating baths with reaction products of pyrazole compounds and bisepoxides to electroplate the photoresist defined features. Such features include pillars, bond pads and line space features.
1. A method comprising:
a) providing a substrate comprising a layer of photoresist, wherein the layer of photoresist comprises a plurality of apertures;
b) providing a copper electroplating bath comprising one or more sources of copper ions; 0.25 ppm to 1000 ppm of one or more reaction products of one or more pyrazole compounds, wherein the one or more pyrazole compounds have a formula:
where R 1 , R 2 and R 3 are independently chosen from hydrogen, linear or branched (C 1 -C 10 )alkyl and one or more bisepoxides, wherein the one or more bisepoxides are chosen from compounds having formula:
wherein R 4 and R 5 are hydrogen; R 6 and R 7 may be the same of different and are chosen from hydrogen, methyl and hydroxyl; m=1-6 and n=1-20; an electrolyte; one or more accelerators; and one or more suppressors, wherein a pH of the electrolyte is less than or equal to 2;
c) immersing the substrate comprising the layer of photoresist with the plurality of apertures in the copper electroplating bath; and
d) electroplating a plurality of copper photoresist defined features in the plurality of apertures at a current density of 0.25 ASD to 40 ASD, to provide the plurality of photoresist defined features with an average % TIR of 0% to 10% and a % WID of the plurality of photoresist defined features is from 0% to 10%.
2. The method of claim 1 , wherein the one or more copper photoresist defined features are pillars, bond pads or line space features.
3. The method of claim 2 , wherein the one or more copper photoresist defined features are pillars having aspect ratios of 3:1 to 1:1.
4. The method of claim 3 , wherein the one or more copper photoresist defined features are pillars having aspect ratios of 2:1 to 1:1.
5. The method of claim 1 , wherein the one or more reaction products are in amounts of 0.25 ppm to 500 ppm.
6. The method of claim 5 , wherein the one or more reaction products are in amounts of 5 ppm to 500 ppm.
7. The method of claim 1 , wherein the current density is from 1 ASD to 30 ASD.
8. The method of claim 7 , wherein the current density is from 10 ASD to 30 ASD.
9. The method of claim 1 , wherein the average % TIR is from 4% to 9%.
10. The method of claim 9 , wherein the % WID is from 3% to 5%.