The Role of Mass Transfer in Removal of Cross-Linked Sacrificial Layers in 3DI Applications

Abstract:

The demand for higher functionality in smaller form-factor electronic devices continues to grow. This growth is enabled in large part by wafer-scale packaging technologies for 2-D, 2.5-D, and 3-D integration. Solder bump, copper pillar, and TSV processes are key enablers for advanced packaging. Sacrificial polymer materials such as photoresist and polyimides are used for patterning and/or passivation steps [1,2]. Typical challenges in removing these materials include long process times, short bath life, corrosion, sludge formation, and filter clogging. This paper presents a novel tool design that addresses these issues by a high rate of hydrodynamic agitation that maintains a thin boundary layer at the wafer surface. The outcome is quick removal and breakdown of the sacrificial layer, independent of pitch and without all the negative side effects.

• Periodical: Solid State Phenomena (Volume 219)
• Pages: 233-236
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.219.233
• Online since: September 2014
• Authors: Mani Sobhian*, Daniel L. Goodman, Dustin Rabideau, Arthur Keigler
• Keywords: Advanced Packaging, Boundary Layer, Mass Transfer, Negative Resist Strip, Polymer Solvation, Resist Removal

References

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