Metallic Trace Contaminant Detection Using SEM/EDX

Surface characterization techniques such as Auger Electron Spectroscopy (AES) and X-ray Photoelectron Spectroscopy (XPS) are commonly used to analyze surface contaminants to determine their elemental composition and/or chemical states. However, one may not have easy access to these techniques due to high cost of ownership and stringent analysis requirements. Thus, an alternative characterization technique, such as Scanning Electron Microscopy (SEM)/Energy Dispersive X-ray (EDX) spectroscopy, could be considered for trace contamination detection if precise elemental composition identification is not required. This paper describes the application of SEM/EDX in detecting trace amounts of Cu on Si die surface. Overall, the results showed that at a low accelerating electron voltage, EDX was able to conclusively detect Cu contaminant.