Low Temperature Material Discovery and Characterization for First Level Interconnect
Section: Packaging

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Project Leaders

Gokhale Shripad, Intel 

Sze Pei Lim, Indium 

Russel Kastberg, IBM 

Call-for-Participation Webinar

Presentation: Call-for-Participation Webinar (April 12 & 13 2023) 

Project Statement & SOW



The Low Temperature Materials for First Level Interconnect Task Force reviewed material and process options currently available or under development to determine whether low temperature materials being used in other levels of electronics assembly could also be used for first level interconnects. Specifically, the group investigated interconnects contained within the first level package, including not only the interconnects of the processor but also those of all interconnects in the package of which the processor is a part.

The Task Force published a white paper that reported their findings from a literature review as well as an industry survey. They identified industrial needs and drivers that require more in-depth study to understand the assembly process challenges, material property versus reliability performance, and the feasibility of employing low temperature materials for first level interconnect. Some of the issues identified include:
  • Temperature-sensitive substrates, die or sensors that require lower processing temperature for most of the current flip-chip or first level interconnect.
  • The need for an interconnect material processing temperature hierarchy for multiple assembly processes that can prevent remelting issues during subsequent reflow process. Lower processing temperatures will reduce energy consumption and minimize carbon footprint.
  • Limited work has been done on the reliability aspect of mixed alloy/hybrid interconnect for first level interconnects in areas such as: high current density, assessing void effects with low temp alloys / materials, understanding the availability of low temperature low alpha material and others.

Project Focus

This new iNEMI project will focus on the need for, and impact of, low alpha low temperature materials. The team will look at the availability and current status of these materials for use in first level interconnect. Modelling will be used to predict the effect of various low-temperature materials and processes on interconnect integrity, followed by experiments on assembled interconnects to observe changes in the characteristics of the low-temperature material compared to standard materials.


For additional information, please contact Masahiro Tsuriya (m.tsuriya@inemi.org).