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Studies the effect of copper stud surface roughness and microstructures on the reliability of solder joint. Advantages of the electroplating-based flip chip process over other solder bumping methods; Experimental procedure; Results and discussion.

Coating of self-assembled monolayer (SAM) on metal surfaces for corrosion protection and adhesion promotion is gaining increasing interest. One of the major obstacles for this technology is the time required for SAM deposition. Preparing SAMs electrochemically has recently come to prominence due to the time reduction of the SAM deposition process. Additionally, the externally applied electric potentials are critically important in enhancing the quality and the surface coverage of SAM on metal substrates. In this work, thiol-based SAM adsorption was investigated under various applied electric potential values and its impact on the adsorption rate constant was studied. The results demonstrated that there exists a SAM adsorption potential threshold in which the adsorption rate constant k t could be one order higher than its normal values. At an applied potential near potential of zero charge ( ϕ pzc ), the charge on the Cu electrode surface is close to neutral, making adsorption of SAM energetically favorable. A SAM mass transport model under the influence of an external energy field was proposed in which both calculated and experimental results were compared and discussed. These findings are shown to provide key mechanistic insight and help rationalize the selection of the externally applied electric potential in order to enhance the SAM adsorption process. [ABSTRACT FROM AUTHOR]

Abstract: This work reports on the adhesion enhancement effects of self-assembled organothiol treatment on copper/epoxy interfaces, as well as a significant reduction in treatment time under the influence of electric potential. The interfacial adhesion has a 20-fold enhancement through the treatment due to improved linkage between the copper substrate and epoxy layer by chemisorbed organothiol molecules. The treatment time was greatly reduced by a factor of 32 from 16hours to 30minutes, thanks to the electrical field assisted method. This was achieved without compromising the maximum adhesion strength, which was shown to be in the order of 97.2 Jm−2. [Copyright &y& Elsevier]