Regional Platform of Surface Analysis
Scientifics and technicals managers :
Jean-François Paul, Pardis SIMON, Nicolas NUNS et Martine TRENTESAUX.
Formulaire de demande d’analyses/Analysis Form à remplir et à renvoyer à firstname.lastname@example.org
XPS KRATOS, AXIS UltraDLD (2009)
The AXIS UltraDLD provides the latest generation tool for high sensitivity muti-technique electron spectroscopy. Spectra may be acquired in either scanned or rapid un-scanned ‘snapshot’ mode by using the delay-line detector (DLD).
The AXIS UltraDLD has the unique capability of parallel imaging using a spherical mirror analyser providing lateral distribution images of elemental and chemical species at the surface.
As with all AXIS spectrometers unrivalled performance on insulators is guaranteed by the use of the coaxial charge neutalisation system
Details of AXIS Ultra DLD components and performance.
Sample analysis chamber (SAC) Stainless steel with double Mu metal screening layer Spherical 267mm diameter, 23 ports (15 line of sight) Ion pump with cryoshroud (220 l/s) Sample treatment chamber (STC) Multiple options offering high flexibility including : Simple load lock and preparation chamber Preparation chamber with additional fast entry lock Catalyst reaction chamber Radial distribution chamber Turbomolecular pump (250 l/s) (oil free option)
Dual anode (Mg and Al Kα source) High power Al monochromator 500mm Rowland circle Quartz toroidal backplane
ELECTRON ENERGY ANALYSER
180° hemispherical analyser 165mm mean radius Spherical mirror analyser
SMALL SPOT SELECTED AREA
defined by insertion of aperture into lens column 110um, 55um, 27um and 15um calibrated analysis areas virtual probe deflected over sample by scan plates (sample remains static)
MCP stack and delay-line detector Scanned and snapshot spectroscopy modes 2D imaging mode
Fully automatic Coaxial low energy electron source
4 axis software and hardware controlled autostage 5 axis software and hardware controlled autostage (optional) Optional fully automatic spot size selection from 15µm to large area
In situ catalysis cell of preparation chamber.
Treatment of the sample under reactionnel stream (H2, CO, NO., O2) for controlled pressure and until T=900°C then transfer in situ towards the chamber of analysis of the spectrometer
VG Escalab 220 XL (1996)
- dual anode (Al-Mg) and monochromator (Al)-Ion gun (noble gases)
- Depth profiling
- Sample cleaning
- Preparation and reactor chambers
XPS main properties
- atomic spectroscopy identifying all the elements (except H)
- binding energies of orbitales sensitive to the chemical environment (notion of chemical shifts)
- in-depth analysis in the10nm range (exponential function) reduced by angular variation
- quantification with use of morphological models
- sensibility in l / 100e of monolayer
- detection of electrons Auger ( XAES)
- depth profile by ionic abrasion
- analysis of the valence band of solids
ISS main properties
- atomic identification of the most superficial coat(layer)
- bad resolution for the elements of high atomic mass
- difficult quantification – need of reference
|In situ catalysis cell of preparation chamber. Treatment of the sample under reactionnel stream (H2, CO, NO., O2) for controlled pressure and until T=500°C then transfer in situ towards the chamber of analysis of the spectrometer|
|Transfer vessel fitted on the preparation chamber|
Ion ToF, Tof SIMS5
Time-of-Flight Secondary Ion Mass Spectroscopy (ToF SIMS) is a very sensitive analytical technique, for many industrial and research applications. This technique uses a pulsed ion beam (here Bi+) to remove both atoms and molecules from the sample surface (< 4 monolayers). The secondary ions removed from the surface are then extracted and accelerated by an electrical field and their masses are then determinate by measuring their time of flight over the analyzer to reach the detector.
The time of flight analysis allowed a very high mass resolution, an unlimited mass range and a parallel detection of all ions.
ToF SIMS applications :
ToF SIMS offers infinity of possibilities to characterize materials, users imagination might be the only limit.
A wide range of industrial and research fields uses ToF SIMS : catalysis, corrosion, polymers, semiconductors, biomaterials, paper, metals, glass, coatings, pharmaceutical ….
The three main modes of analysis are :
- 1) Spectroscopy : High sensitivity in the ppm / ppb range, unlimited mass range, high mass resolution
- 2) Depth profile : Two ion beams operate. While the first beam (Cs or O2) is sputtering a crater, the second beam (Bi+) is progressively analyzing the crater bottom. The depth resolution is better than 1 nm and the sputter speed can be up to 10 µm/h
- 3) Imaging 2D or 3D : ToF SIMS machine offers the opportunity to perform chemical mapping of element or molecules with a high lateral resolution (< 100 nm). By combining depth profile with 2D imaging, it is possible to reconstruct 3D images
Figure 1 : a) ToF SIMS spectrum of Mo-based catalyst in the 107-120 uma range. The isotope cluster calculator (b) confirms that the seven main peaks correspond to Molybdenum oxide
Figure 2 : ToF SIMS depth profile of a Ni/P coating on Ni
Figure 3 : ToF SIMS 2D imaging : Calcium particles are observed on silicon subtract
ION TOF / ToF SIMS V specifications :
Primary gun : Bi, Bi3
Mass Resolution : 104
Mass detection : parallel
Mass range : “unlimited”
Sensitivity : ppm / ppb range
Main application : Static SIMS, Dynamic SIMS
Lateral resolution : < 100nm
Raster precision : up to 1024 x 1024 pixel resolution
Field of view : from µm² to cm²
Sputtering gun : Cs and O2
Depth resolution : ≈ 1nm
Sputter speed : up to 10 µm/h
Ion ToF, Qtac100
The Qtac is a high sensitivity low energy ion scattering (LEIS) instrument. It is extremely surface sensitive, providing elemental and structural characterisation of the top atomic layer. This new generation instrument has been developed to include small spot analysis, surface imaging, and both static and dynamic depth profiling. Its unique surface sensitivity makes the Qtac the perfect tool to study surface processes. The Qtac provides valuable information in many production and research areas on materials such as catalysts, semiconductors, metals, polymers, fuel cells, and biomaterials. Key features are :
- 3000 times higher sensitivity than conventional LEIS instruments
- Quantitative, elemental characterisation of the top atomic layer
- Spectroscopy, imaging and depth profiling capabilities
- Time-of-flight mass filtering for improved sensitivity
- Analysis of rough and non-conductive materials