FOUP mini-environment contamination control optimizing nitrogen purging

We have evaluated FOUP nitrogen purging performance and effect on Semiconductor device characteristics. Due to small inner volume, small amount of nitrogen gas flow is effective to reduce oxygen and humidity inside FOUP. Sealing structure like check valve is important to keep environment inside. Nitrogen purging is found effective to improve Cu interconnect reliability etc. From purging time and particle point of view, we believe purging at equipment loadport should be done through FOUP door/shell opening instead of breathing filter at FOUP bottom. System configuration compatible with current SEMI standard is proposed.