Electron Spectroscopy for Chemical Analysis (ESCA) or X-ray Photoelectron Spectroscopy (XPS)

One of the most powerful analytical tools for evaluating material surfaces and surface compositions is electron spectroscopy for chemical analysis (ESCA).  ESCA, also known as X-ray photoelectron spectroscopy (XPS), is a high-vacuum technique that measures the kinetic energies of photoelectrons emitted from a sample after X-ray bombardment.  These energies provide a signature of elements present in the material.  Slight energy shifts correlate to the elemental bonding structure, thus also providing molecular information.  Since photoelectrons are typically emitted from the top 5 to 10 nanometers of solid surfaces, XPS is one of the most surface-sensitive techniques available for studying adhesion, defects and contamination issues.

ESCA is used routinely for the identification of atoms and molecules at the surfaces of solids.  Ion milling or depth profiling allows the study of composition or elemental distribution within the bulk of the materials.  Almost all elements, with the exception of hydrogen and helium, but including lithium, boron, carbon, nitrogen and oxygen, can be measured by ESCA, giving this technique impressive versatility for compositional analysis.

Our XPS laboratory has extensive expertise with a wide variety of vacuum-compatible materials, including:

• Polymers and plastics
• Thin inorganic layers
• Coatings and capstocks
• Additives, fillers and pigments
• Films, pellets, and plaques
• Metals and ceramics
• Glass, wood, wool, and textiles
• Roofing materials and tiles