1. Electroless copper plating process of N, N, N′, N′-tetrakis (2-hydroxypropyl) ethylenediamine system with high plating rate
- Author
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Zou Wei-hong, Li Xinhai, Gong Zhu-qing, Zheng Ya-jie, and Dan-qing Yi
- Subjects
Mechanical Engineering ,Metallurgy ,chemistry.chemical_element ,Ethylenediamine ,Polyethylene glycol ,Copper ,Crystal ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Plating ,PEG ratio ,Copper plating ,General Materials Science ,Chelation ,Nuclear chemistry - Abstract
Electroless copper plating process of N, N, N′, N′-tetrakis (2-hydroxypropyl) ethylenediamine (THPED) chelating agent was researched comprehensively. The results indicate that plating rate decreases with the increase of concentration for THPED, CuSO4 · 5H2O and HCHO, pH value and bath temperature. The additive of K4[Fe(CN)6] · 3H2O, 2, 2′-dipyridyl and polyethylene glycol(PEG) decrease plating rate and K4[Fe(CN)6] · 3H2O has a bad effect on deposits quality, but 2, 2′-dipyridyl and PEG make deposits quality improve greatly. Low concentration of 2-mercaptobenzothiozole (2-MBT) increases plating rate and improves deposits quality, but decreases plating rate and worsens deposits quality when 2-MBT reaches 5 mg/L. The optimal conditions of this electroless copper plating process are that the concentration of THPED, HCHO, CuSO4 · 5H2O, PEG, 2, 2′-dipyridyl and 2-MBT are 16.8 g/L, 16.0 mL/L, 13.3 g/L, 0.5 g/L, 5.0 mg/L and 2.0 mg/L, respectively, pH value is 12.75, bath temperature is 30 °C. Plating rate reaches 9.54 µm/h plating for 30 min in the bath. The SEM images demonstrate that the surface of copper film is smooth and the crystal is fine.
- Published
- 2005