Preparation and characterization of ultrasonic electrodeposited copper coating

Copper has replaced aluminum as the main interconnect material in VLSI, due to its low resistivity and high electromigration resistance. The property of copper coating is a key factor that determines the reliability of interconnects. A special copper coating was prepared by ultrasonic-electrodeposition method in this study, and the microstructure, hardness, wear resistance, adhesion and corrosion resistance of it were investigated respectively. Test results show that the crystallite size of it is obviously smaller than that of the ordinary electrodeposited copper coating, and the hardness, wear resistance, adhesion and corrosion resistance of it are all evidently enhanced.