IMS 7f / 7f-GEO
UNIVERSAL MAGNETIC
SECTOR SIMS
The
CAMECA IMS 7f is
a magnetic sector SIMS with top performances in trace element depth
profiling and secondary ion microscopy.
Its unique stigmatic optical system allows both
direct ion microscopy and scanning microprobe mode.
The High Mass Resolution capability permits true
elemental analysis by eliminating the numerous interfering ions (56Fe/28Si2,
31P/30SiH,
32S/16O2...).
The HMR capability ensures the instrument's long life, especially in
fields (semiconductors) where materials and thus analytical
problems
(i.e., mass interferences) change rapidly.
The magnetic sector analyzer allows to work with a
high DC extraction field; accordingly, analyzer transmission is
higher by two orders of magnitude than with quadrupole analyzers. High
transmission is mandatory for performing analyses or profiles on
small areas (ex: 50 µm test pads in semiconductor, or µm size particle
analysis), while maintaining excellent detection limits (down to the
ppb level).
High Mass Resolution, High Transmission and
Stigmatic Optics allow the CAMECA IMS 7f
to show benchmark results and application together with the highest sample throughput (sputter
rates up to µm/min).
The IMS 7f-GEO
(see photo above) is a version specialized for
high precision/ high
throughput measurements in geological samples, i.e. REE elements or stable isotopes (H, C, O, S...).
The key features of this new instrument are:
- an improved isotope ratio reproducibility (low sub-permil
level),
- an improved sample throughput for stable isotopes
(X10-50 compared to a IMS 7f) thanks to a new dual FC detection and
a fast
electro-magnetic peak switching,
- a full set of dedicated softwares.
Compared to previous CAMECA IMS instruments,
the IMS 7f series offers:
A more precise depth scale accuracy: obtained
with a new primary ion column incorporating a precise
real-time beam current monitoring.
An improved reproducibility (deep sub-percent
level on implant dose measurement) using multiple hole
sample holders:
obtained thanks to a new secondary ion beam
centering optical system and associated software.
A new PC-Windows automation and evaluation
system, which increases the analysis throughput by allowing
unattended, chained operation. Analyses can be run in a
completely automatic mode with an excellent repeatability
over hours and days.
In
addition, all aperture and slit movement are now motorized
and computer controlled in standard. This ensures best
reproducibility and allows an easier use of
the instrument through memorized settings and recipes.
Dramatic improvements for shallow profiles:
the impact energy can be reduced to very low level (300 eV),
with independent control of the
impact
angle by the
continuous variation of extraction voltage and primary
energy. High speed of erosion (2 nm/min with 500 eV O2+,
45°
on silicon) can be maintained at low energy with the
accel/decel optics for the duoplasmatron. A high sensitivity is now maintained at low
energy even for heavy ions (cesium clusters, noble
metals...) thanks to an Electron
Multiplier post-acceleration.
An eucentric rotating stage
reducing rugosity even on profiles from small dimension
crater, at any position on the sample holder. Ultra High Vacuum is obtained thanks to a
combination of Titanium sublimation with ion or
turbo-molecular pumping. UHV technology ensures excellent detection limits
for light elements (H, N, C, O, ...) and becomes an
important point for ultra-shallow profiling when the sputter rate is
reduced at low energy.
The improved IMS 7f electron flood gun
provides a unique self-compensation mode that makes it
possible to measure depth profiles on complex insulating structures.
