Microfluidic Device for In Situ Observation of Bottom-Up Copper Electrodeposition in a TSV-Like Structure

Abstract

Using a microfluidic device with a replica TSV (Through Silicon Via) structure, in situ observation of the copper via filling was made. Although the bottom-up TSV filling is possible by electroplating with a combination of several additives, the mechanism of bottom-up filling is not yet clear. Observation of the filling behavior is important, and cross sectioning of the TSVs is widely used. But the sectioning process takes some time, and continuous observation of the progress of deposition is difficult. In this study, a replica TSV structure was constructed in a microchannel, and real-time observation using the microfluidic device took place. As an example, extreme bottom-up filling obtained with addition of the leveler was monitored, and the effect of the immersion time before the plating, and progress of electrodeposition toward the via opening, were demonstrated. The observed deposition behavior was discussed in terms of the diffusion-adsorption model, and moderate agreement of the initial locations of deposition between the experiments and a simple 1-d numerical model estimate was obtained.

Synthesis of Quinacridone Derivatives and Their Application as High Performance Levelers in Electroplating

“…Consequently, further investigation into plating additives is warranted. 11 Plating additives utilized in acid copper sulfate plating predominantly encompass inhibitors, accelerators, and levelers, each playing pivotal roles in the copper plating process through distinct mechanisms. 12,13 Inhibitors form a polymer film on the plating surface, curtailing copper deposition, commonly comprising polyether chain compounds like polyethylene glycol (PEG).…”

Shape Control of Metal Nanostructures by Electrodeposition and their Applications in Electrocatalysis

“…For example, metallization of electronic devices can be achieved by Cu electrodeposition. The introduction of organic/inorganic additives to the electrolyte has enabled nano-and micro-scale concave features, such as damascene interconnections, [30][31][32][33] through-silicon vias (TSVs), [34][35][36][37][38][39] microvias, [40][41][42][43] through holes, 44,45 and redistribution layers (RDLs), 46 to be filled with Cu. An important application of electrodeposition involves the development of electrocatalysts for energy conversion and storage.…”