X-Ray Photoelectron Spectroscopy (XPS)
X-ray photoelectron spectroscopy (XPS), also known as electron spectroscopy for chemical analysis (ESCA), is a surface analysis technique that uses characteristic photoelectrons generated by an X-ray beam to analyze the composition and chemistry of the outermost ~5 nm (<50 atoms thick) of the surfaces of solid samples.
Using XPS, we can determine the quantitative elemental composition of surfaces and the chemical states of surface atoms. This information can aid in the identification of molecular species present on surfaces as well as characterize chemical interactions between a sample and its environment. Combining XPS with ion-beam depth profiling is a particularly useful method for precisely determining the thickness and composition of multi-layered microstructures, such as electronic devices, plated metals, and solar cells.
McCrone Associates uses a ThermoFisher Scientific Nexsa X-Ray Photoelectron Spectrometer, a dedicated XPS system with many advanced features, including:
- Sample sizes up to 60 mm square and 20 mm thick
- Sample platforms designed for analysis of powders and fibers
- SnapMap rapid XPS mapping for feature identification and alignment
- Small spot capability—with analysis of features and particles as small as 10 µm, and elemental and chemical state mapping
- High-resolution spectra from a monochromatic X-ray source
- Electron gun charge neutralization for work with non-conductive samples
- Automated ion-beam sputtering for depth profiling
- MAGCIS cluster ion source for working with polymers, organics, and other soft materials
- Total system automation for unattended operation
- Off-line data processing for increased productivity