Article

Revealing ALD Film Growth with Angle-Dependent XPS

Surface Analysis Spotlight: XPS 

by Kateryna Artyushkova     President

Atomic Layer Deposition (ALD) creates ultra-thin, uniform coatings with precise thickness control, which is why it shows up in microelectronics, sensors, and medical devices. Aluminum oxide (Al₂O₃) is one of the most common ALD materials, and it holds up well as a barrier and protective layer even on complex 3D structures.

A critical phase in the ALD process is the nucleation period, where the first few deposition cycles determine how uniformly the film forms on the substrate. Understanding this early growth stage is essential for achieving consistent, high-quality coatings at nanometer-scale thicknesses.

Researchers are using Angle-Dependent X-ray Photoelectron Spectroscopy (ADXPS) alongside StrataPHI® modeling software to non-destructively characterize these ultra-thin films. By collecting XPS data at multiple takeoff angles, ADXPS provides insights into film thickness and composition without the sample damage associated with sputter profiling.

When combined with StrataPHI modeling, researchers can calculate both film thickness and fractional surface coverage, providing a more complete understanding of ALD film formation. In studies of aluminum oxide films deposited on glass substrates, the approach shows how coatings evolve from initial nucleation to a continuous, uniform layer.

Key Highlights

• Non-destructive analysis of ultra-thin ALD films using angle-dependent XPS.
• Simultaneous measurement of film thickness and fractional surface coverage.
• A clearer picture of nucleation behavior in the first ALD cycles.
• No sputter-induced damage, preserving the integrity of delicate thin films.
• Improved process optimization for nanometer-scale coatings and advanced device manufacturing.
• High-throughput metrology potential for semiconductor, sensor, and medical device applications.

The combination of ADXPS and StrataPHI delivers a powerful solution for thin-film metrology, helping researchers and manufacturers gain deeper insight into ALD growth mechanisms and optimize the performance of next-generation devices.

To learn more about angle-dependent XPS, please join us for Dr. Kateryna Artyushkova’s presentation “Non-Destructive Characterization of Film Thickness and Fractional Coverage Utilizing XPS and StrataPHI” at ECASIA 26 on Tuesday, Sept 15 at 10:00 AM.