Used for precise and quantitative 3-dimensional elemental mapping of chemical
heterogeneities in materials at the atomic scale. Its lateral and depth resolution
are the highest of any elemental analysis instrument. The Advanced LASER Assisted
mode permits the Analysis of semiconductors and low conductivity materials.
Developed in collaboration with the University of Rouen ?France, world leading
group in the fields, CAMECA’s LA-WATAP combines the ultimate performance of a
research tool (femto-second LASER, Advanced Delay Line Detector ADLD) with high
throughput ans flexibility (data rate, FIM, large storage chamber, etc.) for
Laser-Assisted 3D Atom Probe for Materials & Semiconductors
The CAMECA LA-WATAP is a high performance Tomographic (or 3D) Atom Probe, providing
quantitative atomic scale 3D elemental mapping of chemical heterogeneities in materials.
The LA-WATAP offers the following key advantages:
• Analysis of semiconductor materials with near-atomic depth resolution
thanks to flexible (IR / visible /
UV) ultrafast (400fs) laser setup.
• Excellent mass resolution even on low thermal conductivity materials.
• Large area of analysis (up to 100 nm in diameter) for a better statistics on
• Fast acquisition rate: ~15 min. needed for collecting 1E6 atoms.
• Best quantitative results with the exclusive Advanced Delay Line Detector
(ADLD) and its benchmark multi-hit performance.
• Flexible and fast dedicated FIM (Field Ion Microscopy) detector for
Atomic scale depth resolution in semiconductors
The interaction of ultrafast (400fs) pulses of polarized light with a small tip (radius 10-100nm) results in
non-linear effects confining the polarization to the skin of the tip apex. Combining this with a DC electrical
field and a moderate heating of the tip, the evaporation of ions can take place without dramatic loss of spatial
Excellent depth resolution is evidenced in the 3D AP analysis of the silicon sample shown
on right hand slide (Image 1). The
atomic planes are directly visible in the reconstructed volume (4x4x20nm), without any data treatment.
A large Field Of View
The 3DAP Field Of View is determined by the instrument geometry (tip-detector distance and detector size)
but also by the tip itself (radius, cone angle and material evaporation field). Smaller tip radius and
lower evaporation field will result in lower FoV. Note that the radius increases during the analysis and
the DC voltage is progressively raised in order to regulate the evaporation flux. The LA-WATAP typically
records volumes of 50-100nm diameter by 100-200nm depth, resulting in files of several tens of millions
ions, in a few hours (depending on requested evaporation flux that is sample-dependent).
The Laser evaporation mode allowed analysis of the above TbFe/Co multilayer, too fragile to be analyzed in
HV mode. Zooming inside the Large Field Of View reveals atomic plane depth resolution and dissymetric
interfaces (sharp and diffused) linked to layer growth conditions
(See image 2).
Flexible Laser set-up
The response of a material under Laser illumination depends on its nature, its shape and on the
wavelength of the Laser. The LA-WATAP offers flexible Laser setup, ensuring optimized analysis
conditions for all materials. The operator can easily select the most appropriate wavelength for
any given sample (See image 3):
I.R. (1030nm),visible (515nm), or
Analysis of a 12nm thick SiO2 layer. The use of UV facilitates the analysis and quantification on
electrically insulating materials