Electrodeposition of solder for flip-chip bonding is studied in the form of a pyrophosphate/iodide tin-silver alloy bath. The objective is to obtain a uniform alloy composition, with 3.8 At.% silver, over a larger area. This specific alloy will provide an eutectic solder melting at 221°C (or 10°C below pure tin). Depositions on a rotating cylinder electrode (with current screen), followed by composition measurements, provided useful information on the relationship between current density and alloy composition. Preliminary experiments with alloy plating on silicon substrates, with and without photoresist, have shown a stable and promising alternative to pure tin and tin-lead alloys for flip-chip bonding applications.
|Title of host publication||196th meeting of the Electrochemical Society|
|Publisher||The Electrochemical Society|
|Publication status||Published - 1999|
|Event||196th Meeting of the Electrochemical Society - Honolulu, Hawaii, United States|
Duration: 17 Oct 1999 → 22 Oct 1999
|Conference||196th Meeting of the Electrochemical Society|
|Period||17/10/1999 → 22/10/1999|