Planned project within the framework of CORNET: Advanced model-based joining with reactive multilayers

Short summary A German consortium is looking for international SMEs and research institutes (except from Belgium) for participation in a Collective Research Networking project starting this year. The topic is advanced model-based joining with reactive multilayers. The international partners sought should come from various sectors e.g. microelectronics, packaging, medtech, materials etc., among others and help to open up new applications. One benefit is a higher process reliability for some applications.

Full description A consortium of a German university of applied sciences and two German research institutes (one of them is consortia leader) are looking for international SMEs except from Belgium for a CORNET (Collective Research Networking) project. Problem Statement: For several years, reactive multilayer systems (RMS) have been investigated for application in packaging and interconnection technology. For broad industrial use, a significantly improved flexibility with respect to further RMS material combinations (e.g. Zr/Si (zirconium/silicon)) is necessary. This refers to a larger variety of adjacent components, a reduction of required pre-tests by numerical simulations and a larger choice of industrially applicable foils. In a precursor project, a 2D simulation model for the two systems Ni/Al (nickel/aluminum) and Zr/Al (zirconium/aluminum) has already been developed and tested, which allows the prediction of not yet physically produced and not experimentally characterized RMS films. This already enables higher process reliability for some applications as well as improved flexibility in reactive joining. In addition, 3D simulations for real functional samples have been carried out and validated with the help of experimental data. In the high-energy Zr/Si system, on the other hand, an unexpected difficulty has arisen. Here, additional intermediate layers, e.g. of aluminum, have to be incorporated for safe multilayer fabrication. Since Zr/Si/Al is a ternary system, it can currently only be studied in a simplified simulation model that requires measured values of existing RMS. Ternary RMS, e.g. Zr/Si/Al, are expected to have a higher specific enthalpy of reaction and lower cost of fabrication due to the lower overall thickness required, compared to the binary systems already investigated, e.g. Ni/Al. This is an important contribution to increasing the economic viability of RMS technology. In addition, ternary RMS allow the use of brazing alloy and thus a higher temperature resistance of the joined components. Furthermore, due to the lower shrinkage, these materials tend to significantly reduce cracking in the reacted RMS. The latter points promise a further increased choice of joining combinations and thus flexibility for companies. Project Objective: The objectives of the proposed transnational project are to increase the available joining combinations in order to achieve more flexibility for the companies and to obtain a further deepened process understanding of reactive joining, especially with regard to the dynamic aspects. For the latter, the aim is to determine the spatial and temporal heat and stress distribution both within the joining zone and in the adjacent component. The following focal points are to be set here: - Extension of the mathematical model from binary to ternary systems (e.g. Zr/Si/Al) - Inclusion of inhomogeneities in the simulation models (roughness, ripple, anisotropy) - More flexible adaptation of reaction properties (energy, velocity, etc.) to the application as well as inclusion of further real assemblies for validation purposes - Variation of ignition positions and methods in 3D models, strategy for optimization of multi-point ignition depending on component geometry - Numerical simulation of stress distribution in the component at different energies and depending on RMS ignition positions - Physical development of ternary multilayers with respect to reproducibility and safe layer deposition - Change of period thickness in a multilayer (2 or 3 zones) For this project, the consortium is looking for new international cooperation partners (research organizations and SMEs) in order to spread the existing knowledge, to gain a deeper physical understanding and to open up new applications. They look for partners from all eligible countries except from Belgium.

Advantages and innovations Development of reactive multilayer systems (RMS) used in packaging technology for the bonding of components. In the precursor project, a 2D simulation model for the two systems Ni/Al and Zr/Al has already been developed and tested, which allows the prediction of not yet physically produced and not experimentally characterized RMS films. This already enables - higher process reliability for some applications as well as - improved flexibility in reactive joining. In addition, 3D simulations for real functional samples have been carried out and validated with the help of experimental data.

Technical Specification or Expertise Sought Please see below partner sought and expected role

Contact / source: NEXT EEN Widgets (europa.eu)