A Novel Vacuum Packaging Process Using Sputtered Copper Layer as Non-Evaporable Getter Activated by Microwave

This study reports a novel process that uses a sputtered copper layer which is widely used in the packaging process, as a non-evaporable getter to absorb the oxygen generated by the silicon-glass anodic bonding process. The copper layer is activated locally by microwave plasma asher because of the microwave heating of the copper. The residual O2 in the cavity formed by anodic bonding may also be excited into oxygen plasma, which reacts with the copper layer. The experiments show that the oxygen content in copper increased by two to four times after 30 min of microwave treatment.