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The Cameca NanoSIMS 50 ion microprobe was delivered to the
Max-Planck-Institut für Chemie in spring 2001. The Nanosims 50 (Fig. 1) is
a new type of secondary ion mass spectrometer that is characterized by three
fundamental features:
(1) High lateral resolution (down to <50
nanometers for Cs+ primary ions and 150 nanometers for O-
primary ions; cf. Fig. 2).
(2) High detection efficiency for secondary
ions (i.e., high transmission through the mass spectrometer) at high mass
resolution (Fig. 3).
(3) Parallel detection of up to six
isotopes.
The combination of these features is unique to the NanoSIMS
50, making it a valuable tool for research projects in cosmochemistry and
astrophysics and atmospheric chemistry. The NanoSIMS 50 is primarily used for
the study of presolar grainsand aerosol particles and it has been named
MADONNA
(MAinz Dust Observatory for the Detection of
Nanoscale Nuclear Anomalies).
Figure 1: The NanoSIMS 50 ion
microprobe at the Max-Planck-Institute for Chemistry.
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Figure 2
: Secondary ion images of the isotopes 12C, 13C,
28Si, and 30Si from a synthetic silicon carbide grain
(about 2 micrometers in diameter) produced under bombardment with
Cs+ primary ions. These images were acquired simultaneously on 4
detectors. The lateral resolution is approximately 100 nanometers. |
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Figure 3
: Relative transmission (ratio of detected to produced secondary ions) as a
function of mass resolution power for three types of ion microprobes. Up to a
mass resolution of 6000 the NanoSIMS 50 and the IMS1270 have comparable
transmissions while that of the IMS3f is lower by a factor of 10 to 20.
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© Copyright 2005 Max-Planck-Institut für Chemie,
NAMIP Group |
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