X-Ray Photoelectron Spectroscopy (Allentown Lab)

Analysis to provide quantitative elemental composition information and chemical states of components

X-ray photoelectron spectroscopy (XPS), sometimes referred to as electron spectroscopy for chemical analysis (ESCA), analyzes surfaces on the nano-scale to provide chemical information and, with ion sputtering, through a depth to obtain an elemental profile. XPS provides quantitative data of the elemental composition on the surface of a material and is a unique technique for studying surface chemistry of thin films, residues, and surface pitting. This can assist in contamination issues, identifying unknown stains or blemishes, and studying the bonding characteristics.

The scientific team at Intertek Allentown uses XPS to study:

Thin Films
Coatings
Contamination
Surface Defects
Semi-Conductors
Residues
Unknown Substances
Differences between surface and bulk material

We can use XPS to analyze for bonding state information and elemental composition of materials.

XPS Instrument Capabilities

Instrument	X-ray Source	Detection Limit	Analysis area	Sample Size	Depth Profiling	Misc
PHI 5000 VersaProbe	Aluminum monochromatic	0.1 atomic percent	10 µm to 200 µm	Up to 7 mm height and 90 mm width; Contact regarding larger sizes	Up to 500 nm deep	Inert transfer for air sensitive materials; Sample must be ultra-high vacuum compatible

Industry specific questions that XPS can help answer:

What is this residue on my product?
How thick is this film or coating on my product?
How deep does this surface contamination penetrate?
What is the composition of a non-oxidized surface of my sample?
What is the composition of my thin film?
Is the chemical composition of my film consistent?
What is causing my coating to fail?

Intertek Allentown hosts a wide variety of analytical techniques and instruments. Our team can easily adapt our analysis plan to meet any questions that come up during analysis. Some examples of how our integrated approach can help you:

Time of Flight Secondary Ion Mass Spectroscopy (TOF-SIMS) - A technique for molecular identification of materials based on their mass that can assist XPS analysis by identifying molecules present on the surface of materials.
X-Ray Reflectance (XRR) – A technique where x-rays are reflected off a flat sample to generate an interference pattern from which layer thickness and density can be determined. This technique is dependent on knowing the composition of a thin film which can be accurately determined by XPS.
Scanning Electron Microscopy (SEM) – XPS can determine the chemical profile of surface defects, but does not have the robust imaging capability that SEM brings to fully understand what is happening at the surface of a sample. Size, shape, and other visual information can be extremely valuable for correct analysis of a feature.
Atomic Force Microscopy (AFM) – Otherwise known as Scanning Force Microscopy, AFM can also be used as a complement to XPS to study surface topology and physical properties on a nanometer scale. Surface imaging is near atomic resolution, measuring atomic level forces at the sample surface.