Characterization and control of microcontamination for advanced technology nodes and 300-mm wafer processing: overview and challenges

Advanced process technologies have been introducing many unseen problems on process yield and device reliability. Microcontamination, which enables defects causing electric faults, has also been hard to understand, detect, and control. In this paper, the requirements and methodologies for contamination control in advanced technologies such as at the 90-nm processing technology node and immersion lithography using 300-mm wafer processing were addressed. Combining techniques of vapor phase decomposition (VPD) and wafer outgassing system (WOS) for characterizing the very low levels of surface metallic and organic contaminants on 300-mm wafers makes a front-end process capable of realizing and deploying the necessary controls. Applying liquid chromatography-mass spectrometry (LC-MS) in the identification of contaminants of immersion fluids is a new experience for 193-nm lithography technology. Furthermore, the wafer-environment contamination controls, such as airborne molecular contaminants (AMCs), process critical material assurance and point-of-use quality are reviewed in the paper. This paper concludes by discussing the challenges for characterization and control of microcontamination in future manufacturing technologies.