Gate oxide damage reduction and antenna yield improvement using lowtemperature preclean for sub-0.25 μm metallization

摘要

This article describes a new generation of low temperature argon(Ar) sputtering preclean. A ceramic electrostatic chuck (E-Chuck) wasintegrated to provide active wafer cooling. Wafer temperature, which iscritical to gate oxide degradation in a plasma ion bombardment andcharging environment, was reduced from 250° C to 75° C. Thissignificantly improved the antenna yield due to reduced gate oxidedamage and achieved the same etch performance