High-strength Au–Au bonding for temperature and pressure integrated sensor

With the development of intelligent and integrated electronic devices, leadless integrated sensors have a broad development. One of the most critical processes in TSV (Through Silicon Via) leadless packaging is Au–Au bonding, which the bond strength determines the success or failure of sensor preparation. In this research, the effect of the bonding temperature on the bonding strength was studied for the designed the temperature and pressure integrated sensor. To further increase the bonding strength, plasma treatment of the metal surface was applied. The influence of various plasma atmospheres and treatment times on the surface morphology, surface hydrophilicity, chemical state and the bonding rate were studied. And bonding interfaces under different bonding conditions were characterized. Finally, after 120 s of O 2 plasma treatment and bonding for 1 h at 450 °C and 4000 mbar, the bond strength was increased by 68%, reaching 27 MPa, which enhances the feasibility of the preparation of temperature and pressure integrated sensors.