Metal Diffusion Bonding
Metal diffusion bonding for precise interfaces and alignment
Introduction
Metal diffusion bonding, also known as Thermo compression bonding (TCB), is a direct solid-state diffusion bonding process and is based on atomic contact. In this bonding technique, two metals are brought into contact by applying heat and force simultaneously after which the atoms diffuse to form the bond interface. TCB is widely used in the production of RF MEMS, light emitting diodes (LEDs), laser diodes as well as power devices.
TCB provides hermetic sealing of packaged internal structures and electrical interconnects in a single process step. Because of their high diffusion rates, Au, Al and Cu are the most established materials that are used in TCB. Compared to Al and Cu, Au requires less temperature for diffusion and has an added advantage of not becoming oxidized. The diffusion rate depends on the chosen temperature and applied pressure where the atoms diffuse between crystal lattices. Here, grain boundary and bulk diffusion takes place in addition to standard surface diffusion.
In this technology, wafer-level bonding is achieved at low temperatures without the application of an electric field. Nevertheless, good control of CTE (coefficient of thermal expansion) and synchronized wafer expansion is important to prevent any resulting stress and alignment shift during bonding. Furthermore, the applied force and its uniformity are important, which also depend on the metal density (features) and size of the wafers. In TCB, the bonding temperature and the applied pressure are inversely proportional, which gives a feasibility to tailor the bonding parameters.
Features
- Electrically conductive
- High fracture toughness
- Small bonding frames
- Hermetic sealing
- Very good post-bond alignment
- No contamination
- No or very little deformation
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Events
SEMICON EUROPA 2026
Treffen Sie das EVG-Team am Stand #B1241 und besuchen Sie unsere Poster-Präsentationen auf der APC:
"Software-Driven Strategies for Advanced Multi-Die Patterning in Digital Lithography" von Business Development Manager Dr. Ksenija Varga und “Leveraging Advanced Bonding Technologies to Enable Scalable Co-Packaged Optics Architectures” von Business Development Manager Elisabeth Brandl.
Hier finden Sie nähere Infos zum Program.
Darüber hinaus wird unser Corporate Sales & Marketing Director Thomas Uhrmann Teil der Podiumsdiskussion „SEMICONDUCTOR TOUR 2026“ sein, welche von der YOLE Group am 12. November im Novotel München Messe veranstaltet wird. Für mehr Informationen klicken Sie hier.
Industrial Print Integration Conference (IPI) 2026
Hören Sie sich unsere Keynote an: “Advancing AR/VR and CPO: EV Group’s Inkjet Solutions for Next-Generation Optics” gehalten vonJohanna Rimböck (Technology Development).
Mehr Informationen zum Programm finden Sie hier.
EPTC 2026
Besuchen Sie unseren Stand #2 & hören Sie sich unsere Vorträge an:
"Scalable Manufacturing Approaches for Co-Packaged Optics via NIL and Advanced Wafer Bonding" gehalten von Director Business Development Dr. Bernd Dielacher und
“Advancing 310×310 mm² Panel Level Packaging: High Throughput Pathways to High Yield 3D Integration” und “Plasma–Enabled Die Singulation on Film Frame Carrier for Advanced HBM and Logic Die Integration” von Business Development Manager Dr. Ksenija Varga.
“Hybrid Bonding Overlay Reduction Through Lithographic Pre-Compensation of the Residual Fingerprint” von Technical Program Manager Sander Grosemans.
EVG & Brewer Science: “Polymer Buffer Layer Enabling a Novel RDL–First Process Flow using a Silicon Carrier and IR Laser Debonding Technology” shared presentation, Peter Urban & Brewer Science.
EVG & CEA–Leti: “Nanometer Level Chip- Scale Transfer Enabled by IR Laser Debond Technology”.
Mehr Infos zum Programm hier.
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