Thin film analysis in microprocessor manufacturing using Auger electron spectroscopy

Abstract

In the semiconductor industry, Auger electron spectroscopy is widely used for advanced process control and physical failure analysis. Quantified Auger depth profiles are typically based on the peak-to-peak intensities of the derivative Auger spectra and do not fully use the spectral information of the Auger peak. More sophisticated data processing procedures based on linear least square (LLS) fits are capable of separating superimposed Auger peaks thus providing access to any chemical state information.One example of an Auger analysis using LLS is the investigation of the interface reaction between copper interconnect and its silicon nitride based cap layer. The effect of the local environment on the silicon LVV Auger peak enables one to identify the chemical bonding of the modified copper. Another study of lead-tin alloy bump surfaces using chemical state analysis provides information about inhomogeneities of the tin oxidation and segregation.

Auger Electron Spectroscopy

“…It is interesting to note that AES has also been used to characterize room temperature single electron transistors (SET), which represent a potential breakthrough in the quest for even smaller devices [59]. Because of shrinking device dimensions, AES has recently become a vital tool in the semiconductor industry for process control and failure analysis [60]. For example, because of its excellent spatial resolution and nondestructive nature, AES is ideally suited to identify and characterize submicron semiconductor defects (as small as 500 Å) which are beyond the capabilities of conventional methods based on X-ray dispersive analysis tools [61].…”