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

Abstract

This article describes a new generation of low temperature Argon (Ar) sputtering Preclean. A ceramic electrostatic chuck (E-Chuck) was integrated to provide active wafer cooling. Wafer temperature, which is critical to gate oxide degradation in a plasma ion bombardment and charging environment, was reduced from 250°C to 75°C. This significantly improved the antenna yield due to reduced gate oxide damage and achieved the same etch performance.