Key Atmospheric Plasma Solutions Lead Reliable Hybrid Bonding

Surface pre-treatment is crucial for achieving high-quality hybrid bonding in advanced semiconductor packaging. This paper presents the development and characterization of a Medium Frequency Atmospheric Pressure Dielectric Barrier Discharge (MF AP-DBD) plasma system designed for this application. Unlike conventional RF or Microwave plasma systems that typically require expensive noble gases like argon, the developed MF AP-DBD source effectively utilizes cost-efficient high-concentration nitrogen as the working gas, combined with a small percentage of hydrogen for reduction. We evaluated the system’s performance through experiments focusing on copper oxide reduction effectiveness, treatment uniformity across its 320 mm width, and the influence of key operating parameters. Results demonstrate that the plasma effectively reduces copper oxide. Uniformity tests confirmed satisfactory treatment across the width, with parameter tuning achieving over 80% effective width under optimized conditions (e.g., 600-1000W, 60-100slm N2 with 1 vol% H2 at 1mm/s). Furthermore, a ground electrode design successfully maintained substrate electrostatic charge below 10V despite the high operating voltage. These findings highlight the potential of the MF AP-DBD plasma as a cost-effective, uniform, and electrostatically controlled solution for surface pre-treatment in hybrid bonding.