Non-Destructive Characterization and Metrology for Ultra-Thin High-k Dielectric Layers

Angle‐resolved X‐ray photoelectron spectroscopy (ARXPS) has been used to characterize non‐destructively silicon oxynitride and high‐k film samples. The ARXPS data have been processed to provide accurate and precise measurements of thickness of surface and interface layers. Concentration depth profiles have been reconstructed from the ARXPS data to provide elemental and chemical state distribution information. For silicon oxynitride samples, nitrogen doses have been calculated from the concentration profiles, thereby accounting for the distribution of the nitrogen within the oxynitride layer. A comparison of ARXPS with modeled single‐angle XPS experiments illustrate the potential errors in calculation of both thickness and dose using the latter technique. Sputter depth profiles are also shown to contain potentially misleading information when compared to reconstructed ARXPS depth profiles.