The X-ray Photoelectron Spectroscopy (XPS) is used for surface analysis in SHyNE’s NUANCE/Keck –II facility. How it works: A focused monochromated X-ray beam bombards the surface of a specimen and generates photoelectrons and through the analysis of the kinetic energy of the photoelectrons, the binding energy can be calculated. Therefore the elements (and their chemical or electronic state) within the top 10 nm ofa surface can be identified.
The XPS is used to measure:
- elemental composition of the surface (top 0 –10 nm usually)
- empirical formula of pure materials
- elements that contaminate a surface
- chemical or electronic state of each element in the surface
- uniformity of elemental composition across the top surface (or line profiling or mapping)
- uniformity of elemental composition as a function of ion beam etching (or depth profiling)
As with many instruments in the SHyNE facilities, the XPS draws many external and internal users to perform nanoscale research. The XPS has over 100 active users, including Northwestern University’s Department of Material Science and Engineering, Chemistry, Chemical Engineering, Biochemical Engineering and Mechanical Engineering. External users also include the University of Illinois at Chicago, University of Chicago, Loyola University, Cabot Microelectronics, Rubicon Technology and MicroLink Devices.
With its extreme capabilities in exterior analysis procedures, the XPS has been used to analyze photovoltaic materials, contact lenses, battery materials, semiconductor devices, and nanomaterials. It has also played an important role for the surface science and engineering.
Dr. Xinqi Chen is the facility manager of the NUANCE/Keck-II Facility in SHyNE. He has a background in synthesis and characterization of nanomaterials. Most recently, he is focusing on 2D materials such as MoS2. As facility manager, Dr. Chen trains new users every week, provides technical assistant for users on a 24/7 basis and offers XPS analysis services for internal and external clients. Dr. Chen has been with SHyNE for 11 years and is also an avid tennis player and fan.
If you are interested in using the X-Ray Photoelectron Spectroscopy, please contact Ben Myers at shyne@northwestern.edu or (847) 467-1081.