L-酒石酸錯体浴からのスズ-銀合金めっき [in Japanese] Sn-Ag Alloy Electrodeposition from L-Tartrate Complex Bath [in Japanese]
Access this Article
Search this Article
Electrodeposited tin-silver alloys show promise as lead-free alternatives to solder coating. Eutectic tinsilver alloy film was deposited at 2∼3A/dm<sup>2</sup>, 25°C, and pH 8 using the following bath composition: 0.19M SnCl<sub>2</sub>, 0.01M CH<sub>3</sub>COOAg, 1.0M L-tartaric acid, and 0.2M N-acetyl-L-cysteine. The presence of N-acetyl-L-cysteine markedly promoted silver deposition over a noble potential range.<br>The eutectic tin-silver alloy film consisted of β-Sn and ε (Ag<sub>3</sub>Sn) phases, and its solidus temperature was 221°C. An intermetallic compound layer (Cu<sub>6</sub>Sn<sub>5</sub>) was formed at the interface of the alloy film and copper substrate in heat treatment, forming a Sn-Ag-Cu ternary eutectic (m. p. 217°C) with reactions of Cu<sub>6</sub>Sn<sub>5</sub> and ε (Ag<sub>3</sub>Sn) phases.
- Jitsumu Hyomen Gijutsu
Jitsumu Hyomen Gijutsu 49(7), 759-763, 1998-07-01
The Surface Finishing Society of Japan