X-Ray Photoelectron Spectroscopy / Electron Spectroscopy for Chemical Analysis (XPS / ESCA)
X-ray Photoelectron Spectroscopy (XPS Analysis), also known as Electron Spectroscopy for Chemical Analysis (ESCA), is used to determine quantitative atomic composition and chemistry. It is a surface analysis technique with a sampling volume that extends from the surface to a depth of approximately 50-70 Angstroms. Alternatively, XPS analysis can be utilized for
sputter depth profiling to characterize thin films by quantifying matrix-level elements as a function of depth. XPS is an elemental analysis technique that is unique in providing chemical state information of the detected elements, such as distinguishing between sulfate and sulfide forms of the element sulfur. The process works by irradiating a sample with monochromatic x-rays, resulting in the emission of photoelectrons whose energies are characteristic of the elements within the sampling volume.
Evans Analytical Group® (EAG) uses this technique in a variety of applications to help customers, across a range of industries, with R&D, as well as process development/improvement.
Examples include:
- Identifying stains and discolorations
- Characterizing cleaning processes
- Analyzing the composition of powders and debris
- Determining contaminant sources

- Examining polymer functionality before and after processing to identify and quantify surface changes
- Measuring lube thickness on hard disks
- Obtaining depth profiles of thin film stacks (both conducting and non-conducting) for matrix level constituents
- Assessing the differences in oxide thickness between samples
These insights into a product's chemical makeup allow you to make product and process improvements more quickly, enabling you to reduce cycle time and save money.
With EAG, you also have access to the best facilities, instruments, and scientists available for performing an XPS analysis. We handle many different materials from multiple industries, giving us a wide variety of experience. Plus, our person-to-person service ensures that you will receive answers to all of your questions.
- Surface analysis of organic and inorganic materials, stains, or residues
- Determining composition and chemical state information from surfaces
- Depth profiling for thin film composition
- Silicon oxynitride thickness and dose measurements
- Thin film oxide thickness measurements (SiO2, Al2O3 etc.)
Signal Detected: Photoelectrons from near surface atoms
Elements Detected: Li-U Chemical bonding information
Detection Limits: 0.01 - 1 at% sub-monolayer
Depth Resolution: 20 - 200 Angstroms (Profiling Mode); 10 - 100 Angstroms (Surface analysis)
Imaging/Mapping: Yes
Lateral Resolution/Probe Size: 10 µm - 2 mm
- Chemical state identification on surfaces
- Identification of all elements except for H and He
- Quantitative analysis, including chemical state differences between samples
- Applicable for a wide variety of materials, including insulating samples (paper, plastics, and glass)
- Depth profiling with matrix-level concentrations
- Oxide thickness measurements
- Detection limits typically ~ 0.1 at%
- Smallest analytical area ~10 µm
- Limited specific organic information
- Sample compatibility with UHV environment
- Aerospace
- Automotive
- Biomedical/biotechnology
- Compound Semiconductor
- Data Storage
- Defense
- Displays
- Electronics
- Industrial Products
- Lighting
- Pharmaceutical
- Photonics
- Polymer
- Semiconductor
- Solar Photovoltaics
- Telecommunications
Related Application Notes
- Quantification of APIs at the Surface of Pharmaceuticals by XPS AN465
- CdTe Thin Film PV - Application Discussion BR047
- CIGS Thin Film PV - Application Discussion BR045
- Cause and Location of Delamination of Multi-layer Metal Foil by XPS AN447
- Contact Lenses: Understanding Surface Chemistry Critical to Optimizing Design BN1503
- Evaluation Corrosion Chemistry with m-XPS BN1405
- Evaluation of Cleaning Efficacy BN1422
- • XPS Analysis of Disposable Gloves BN1423
- Accuracy in SiON Thickness and N Dose Measurements by XPS AN412
- Characterization of Oxidized GaAs Wafers by XPS AN377
- Hafnium Oxide (HfO2) Composition and Stoichiometry AN400
- Oxide Thickness Measurements by Electron Spectroscopy for Chemical Analysis AN425
- Physical and Chemical Characterization of Multi-layer Thin Films AN353
- Thin Film Hafnium Oxide (HfO2) Thickness, Composition, and Uniformity Measurements by XPS AN415
- Thin Film Hafnium Silicate (HfSiO) Thickness and Composition Measurements by XPS AN416
- Characterization Methods for Copper Technology AN192
Related Brochures
- EAGLABS Bubble Chart: Analytical Resolution versus Detection Limit BR004
- Materials Characterization Brochure
- PV Materials Characterization for CIGS BR053
- PV Silicon Impurity Analysis BR025
- Materials Characterization for Lithium Ion Battery Technology BR057
- PV Materials Characterization for CdTe BR054
- Typical Applications for Techniques / Periodic Table of Elements BR038
- Biomedical Service Brochure BR003
- Amorphous & MicrocrystallineThin Film PV - Application Discussion BR046
- III-V Multi-Junction PV - Application Discussion BR048
- Silicon Wafer PV - Application Discussion BR044
- EAGLABS X-ray Photoelectron Spectroscopy (XPS) Services TN100
- Your Solution for PV Materials Characterization BR032
- Compound Semiconductors for Optoelectronics - SIMS Analytical Services BR010
- Contamination Analysis for Compound Semiconductors - Analytical Services BR006
- EAG Services Introduction BR011
- EAG Technique Chart BR008




