POINT OF USE ABATEMENT UNIT BY-PASS FOR NF_3-BASED CVD CHAMBER CLEAN APPLICATIONS

摘要

The conversion of NF_3-based CVD chamber cleans from previously used gases, such as CF_4 and C_2F_6, has resulted in significant reduction in PFC emissions but has greatly increased the amount of fluorine in the clean effluent. This increase in F_2 emissions can cause accelerated corrosion in point of use abatement units and corresponding exhaust infrastructure under certain conditions. One solution to this corrosion problem is a bypass loop for the abatement unit. In this design, chamber clean gases are routed directly to the fab exhaust while process gases are directed to the abatement unit. The abatement unit is no longer subjected to high concentrations of F_2, thus reducing the instances of failure by corrosion.