Joining aluminum sheets with conductive ceramic films by ultrasonic nanowelding

Directly joining metal electrodes with ceramic films is desired for many applications in electronic manufacture. In this work, ultrasonic nanowelding was used successfully to join aluminum (Al) sheet onto indium tin oxide (ITO) and aluminum-doped ZnO (AZO) ceramic thin films. The results show that the contact resistance of the nanowelded bonds is as low as that of the conventional silver paste joints, and the contact strength is enhanced dramatically after nanowelding. Compared with Al-ITO joint, the contact stength between Al and AZO is a little higher because of the different roughness at the joint interface. From the rupture interface of the joint zone after stress-strain measurement, domains of Al atoms have been observed, which suggests that a reliable bonding is formed between Al and the ceramic films.