论文信息 - Pulsed electrodeposition of the eutectic Au/Sn solder for optoelectronic packaging

Pulsed electrodeposition of the eutectic Au/Sn solder for optoelectronic packaging

As an alternative to the time-consuming solder pastes and preforms currently being used, a method of electroplating the eutectic Au/Sn alloy has been developed. Using a pulsed co-deposition process, it is possible to plate the solder directly onto a wafer at or near the eutectic composition from a single solution. It has been shown that two distinct phase, Au5Sn and AuSn, can be deposited separately over a range of current densities at compositions of 15 at. %Sn and 50 at. %Sn, respectively. by adjusting the deposition current pulse, it is possible to plate both phases in a layered composite thereby achieving any desired composition between 15 and 50 at. %Sn, including the commercially important eutectic composition.

D. Ivey | D. G. Ivey | B. Djurfors | B. Djurfors

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