Year: 2026
Type: article
Abstract: As advanced packaging continues to drive towards heterogeneous integration, new materials need to be developed to address the many challenges faced in the assembly process. Development of novel materials for the various assembly processes is crucial to ensuring high yield for the assembly process for reliable SiP applications, and high density, fine pitch interconnects. As ultra-fine pitch flip-chips become prevalent in advanced packaging, with reduced standoff of flip-chips and other IC packages, cleaning becomes ever more challenging, especially as the chip and package sizes increase. The shift towards using semiconductor grade ultra-low residue no-clean flip-chip fluxes, which eliminates the cleaning process, is therefore one of the solutions for overcoming these challenges. The flux residue left behind after the soldering process is minimal and is compatible with the underfill or molding materials used in the subsequent processes. Further, adhesive agents, which leave near zero residue, have also been developed to enable fluxless soldering for wafer/die bonding. Another challenge is the warpage induced open joints defects as the chips are becoming thinner and larger, and thermo-compression bonding (TCB), and laser-assisted bonding (LAB) are being explored as alternatives for the typical mass reflow process, to improve process yield with robust flux materials. With more semiconductor chips and smaller components packed into a smaller footprint, the deposition of solder paste for high density SiP applications has become very challenging. For fine feature solder paste applications, the quality of fine solder alloy powder, flux formulations, and solder paste rheology, are crucial to achieve consistent solder paste deposition and good soldering performance. Particularly, for solder paste applications down to 100um or less, fine solder alloy powder, robust flux formulations, and solder paste rheology have been developed to achieve consistent solder paste deposition and good soldering performance. Due to some packaging design where printing of solder paste may not be possible, dispensing or jetting can also be used as an alternative. This presentation will cover innovative materials for advanced packaging and heterogeneous integration, including novel ultra-low residue flux formulations for flip chip attach that is compatible with underfill and molding compound, adhesive agent for fluxless soldering, and solder paste for ultra-fine pitch printing. These novel materials are critical enablers for high density packaging applications. Use cases for high density SiP modules, TCB and LAB, for advanced packaging and 2.5D modules, will be discussed as well.
Source: IMAPSource Proceedings
DOI: 10.4071/001c.173635
Institution: Indium Corporation (United States)
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W7225345334