English (EN) Services Contact Menu Eutectic Bonding EV Group Technologies Eutectic Bonding Eutectic Bonding Eutectic wafer bonding for reliable hermetic sealing Introduction Features Figures Introduction Eutectic bonding, also called eutectic soldering, is where the combination of two or more metals allow direct transformation from solid to liquid state or vice versa at specific temperature without passing two-phase equilibrium. The eutectic temperature is much lower than the melting temperature of the materials that are involved in the bonding process. Eutectic bonding is ideal for high-vacuum applications as this process has very low outgassing. Eutectic wafer bonding is widely used in the MEMS industry for hermetic sealing, pressure or vacuum encapsulation as it allows highly reliable wafer-level processing for devices with the smallest form factors. The most common metals/alloys that are used in eutectic bonding are Al-Ge, Au-Sn and Au-In. However, there are many other material combinations available that can produce a eutectic bonding system. Additionally, the ability of silicon to alloy with metals like Au can also be the basis for eutectic bonding. All eutectic bonds must go through a liquid phase and thus are less sensitive to surface flatness irregularities, scratches and particles, thereby facilitating high volume manufacturing. Bonding temperature, time and pressure are the most important parameters for eutectic bonding where high bond strength can be achieved with low processing temperature and minimum resultant stress. Eutectic bonding can additionally enable hermetic sealing and electrical interconnections in a single process. Compared to other intermediate layers, such as adhesives or glass-frit, eutectic bonding also promotes better out-gassing and hermeticity. Features Vacuum encapsulation Defined pressure encapsulation Conductive interface Hermetic sealing Good mechanical strength Narrow bond lines Good post-alignment bonding Low applied force Reversible process High fabrication yield Figures SEM cross section image of GaAs/InP wafer pair bonded with Au-Sn eutectic metal system. SEM image of a MEMS device bonded to an ASIC using Al-Ge eutectic bonding system. Events SEMICON Europa 2021 MESSE MÜNCHEN | Co-located with Productronica 16.11. - 19.11.2021 Munich, Germany SEMICON Japan 2021 Venue: Tokyo Big Sight/Online 15.12. - 17.12.2021 Tokyo, Japan Show all events Related downloads EVG Solutions for MEMS Brochure - 2.28 MB EVG®500 Series Brochure - 1.83 MB EVG GEMINI® Series Brochure - 2.12 MB EVG Solutions for R&D Brochure - 1.66 MB Talk to our EVG technology experts! Questions? Contact form Related products GEMINI® Automated Production Wafer Bonding System EVG®501 Wafer Bonding System EVG®510 Wafer Bonding System EVG®520 IS Wafer Bonding System EVG®540 Automated Wafer Bonding System EVG®560 Automated Wafer Bonding System Questions about our technologies? Contact the EVG experts Send us a message Related News From wafers to power electronic applications: new consortium to create European supply chain for silicon carbide semiconductors Oct, 2021 EV Group Celebrates “40+1 Year” Anniversary with Exciting Live Event at Corporate Headquarters Sep, 2021 Applied Materials Introduces New Technologies and Capabilities for Accelerating the Semiconductor Industry's Heterogeneous Integration Roadmap Sep, 2021 EV Group Products Technologies Company Careers Social Media LinkedIn Facebook Twitter YouTube Join our newsletter We will send you updates on new products and technologies. Your Email Subscribe © 2021, EV Group (EVG) Imprint Privacy Policy Terms of use