cmem @ unm: X-ray Photoelectron Spectrometer at Surface Characterization Facility

Kratos AXIS ULTRA X-ray Photoelectron Spectrometer offers advanced capability of high sensitivity, high energy resolution and high lateral resolution image analyses.

Technique characteristics:

Sampling depth:

<10 nm
variable with ARXPS

Spectroscopy:

large area analysis: 300x700 µm
small areas analysis 100 - 15 µm

Imaging

parallel and real-time
FOV (200-700 µm)
lateral resolution: <5 µm

Primary sources:

dual anode Mg
monochromatic Al

Ion source

sputtering and cleaning samples

More characteristics

Types of analytical problems

General characteristics:

Identification of all elements (except H and He) present in the outermost 10 nm of a surface in concentrations > 0.1 atomic %
High energy resolution: information about the molecular environment (oxidation state, bonding atoms, etc.)
Quantitative: determination of elemental surface composition (±2% or better)

Fast parallel imaging:

Information on lateral variation in composition (spatial resolution down to 5 µm)
Real-time parallel detection that allows high quality chemical images to be obtained in only a few seconds
Multispectral image acquisitions combine high energy resolution and high spatial resolution allowing analysis of lateral distribution of chemical states

Multi-point spectroscopy:

The incorporated electrostatic deflection system allows easy multi-point analysis to be carried out from within the imaged field of view without translating the sample
Small area analysis from down to 15µm areas by conventional experiments
Small area analysis from down to 1µm with multispectral image acquisitions and multivariate image analysis methods

Depth profiling

Non-destructive depth profiling using Angle-Resolved XPS in outer 10nm
Destructive depth profiling several hundreds of nm into the sample
Ion gun for in-situ sample cleaning

Sample requirements

Insulating and conducting samples analysis through the incorporation of the Kratos patented charge neutralization system
Sample must be compatible with ultrahigh vacuum

Types of analytical problems solved:

High spatial resolution analysis of chemical heterogeneities and detection of chemical phases in multicomponent samples (polymer blends, nanocomposites, FIB-milled samples) through combination of imaging and multi-point small area analysis.
Determination of the oxidation states of elements (catalysts, metal alloys, product of corrosion) - see Case studies
Analysis of molecular orientation and thickness determination via ARXPS for multilayered samples(self-assembled layers, thin organic layers, semiconductors, nitrided gate oxides) - see Case studies
DNA microarray analysis
Depth profiling through sputtering of inorganic samples
Polymer isomer analysis through Valence Band Spectra
Failure analysis, reverse engineering

For more details, please contact us (kartyush@unm.edu).

center for micro-engineered materials

+X-ray Photoelectron Spectroscopy