Laboratory for X-Ray Photoelectron Spectroscopy (XPS)

The PHI Versaprobe 3 AD XPS spectrometer (PHI, Chanhassen, US), which is partially owned by the Advanced Materials Department of Jožef Stefan Institute, is located at the National Institute of Chemistry (NIC) in Ljubljana. This advanced system is equipped with pumps, valves, and an intro chamber that maintain ultra-high-vacuum conditions in the main analysis chamber.

X-ray Photoelectron Spectroscopy (XPS) is a surface-sensitive technique used for chemical analysis of the topmost 5 nm of a sample. In our setup, we use a monochromated Al-Kα X-ray source with a spatial resolution as fine as 10 µm to irradiate solid samples, whether conductive or non-conductive.

In addition to standard XPS components, our system includes two ion guns. An argon ion gun is used for sputtering inorganic materials and neutralizing floating samples. For organic materials or gentle surface cleaning (e.g., removing residual carbon), we use an argon gas cluster ion beam (GCIB) gun for soft sputtering.

The sample stage offers temperature control ranging from -196°C to 800°C, supporting both heating and cooling applications. Angle-resolved measurements are also possible, enabling analysis of near-surface regions with greater depth sensitivity.

The X-ray source can be switched to an ultraviolet (UV) source to probe valence states instead of core levels, expanding the analytical capabilities of the system.

Additionally, the XPS spectrometer is connected to a glove box, allowing the transfer of samples that are sensitive to oxygen or moisture. A vacuum suitcase is available to transfer samples from other vacuum-based systems (e.g., PLD) to the spectrometer, ensuring they remain contamination-free prior to analysis.

Related equipment

X-ray photoelectron spectrometer (PHI, Versaprobe 3 AD)

Person responsible: Blaž Jaklič

PHI Versaprobe 3 AD spectrometer (PHI, Chanhassen, US) is equipped with pumps, valves, and load-lock to maintain ultra-high-vacuum conditions in the main chamber. X-Ray photoelectron spectroscopy is a surface-sensitive technique for analyzing the topmost 5 nm of the sample. In our system, a monochromated Al-Kα x-ray source with spatial resolution as low as 10 µm is used for irradiating solid sample surfaces that can be either conductive or non-conductive. Apart from standard XPS equipment, two ion guns are connected to the main chamber. Argon ion gun is used for sputtering of inorganic materials and neutralization of floating samples, while we use an argon gas cluster ion beam gun (GCIB) for soft sputtering of organic materials or removing residual carbon from the samples. Heating (max. 800°C) and cooling (min. -196°C) of the sample stage are also available. Angle-resolved measurements are possible in order to analyze near-surface regions. X-ray source can be switched to an ultraviolet source in order to probe valence states instead of core states. XPS system is connected to the glove box that allows the transfer of samples, sensitive to oxygen or moisture. The system also allows vacuum transfer from other vacuum systems (PLD) to the spectrometer via vacuum suitcase to prevent any contamination of the samples before XPS analysis.

Technical details

  • Al-Kα x-ray source; spot size 10–200 um
  • Ion sputtering sources: argon ion gun / gas cluster ion beam gun
  • Heating stage: RT - 800°C
  • Cooling stage: -196°C - 400°C
  • Angle resoved measurements
  • UV source
  • Transfer options: glove-box transfer/ UHV transfer

*Financed by National Institute of Chemistry.