Paper
Characterization of Cu/Cu Bonding Interface Prepared by Surface Activated Bonding at Room Temperature
- Authors:
- Yuko Yuko Ichiyanagi; Jun Utsumi
- Abstract
- We studied Cu/Cu direct bonding by surface activated bonding at room temperature for the application in 3D integration. The Cu film surfaces were activated by irradiating with an Ar fast atom beam in a high vacuum. For the successful bonding, it is necessary to sufficiently remove the native oxide layer and contaminants on the sample surface. The microstructure of the Cu/Cu direct bonding interface was investigated by transmission electron microscopy, and no intermediate layers or voids were visible at the bonding interface. The absence of oxide at the bonding interface was confirmed by energy dispersive X-ray spectroscopy and electron energy loss spectroscopy. Tensile testing revealed that the bonding strength of the Cu-Cu interface was higher than 8 MPa. The current-voltage characteristic of the bonding was linear.
- Keywords
- Surface Activated Bonding; Room Temperature Bonding; Cu Film; Bonding Interface; Transmission Scanning Microscope (TEM); Energy Dispersion Spectroscopy (EDS); Electron Energy Loss Spectroscopy (EELS)
- StartPage
- 150
- EndPage
- 158
- Doi