  Microscope mode imaging for secondary ion mass spectrometry is a technique
with the promise of simultaneous high spatial resolution and high speed imaging
of biomolecules from complex surfaces. Technological developments such as new
position-sensitive detectors, in combination with polyatomic primary ion
sources, are required to exploit the full potential of microscope mode mass
spectrometry imaging, i.e. to efficiently push the limits of ultra-high spatial
resolution, sample throughput and sensitivity. In this work, a C60 primary
source is combined with a commercial mass microscope for microscope mode
secondary ion mass spectrometry imaging. The detector setup is a pixelated
detector from the Medipix/Timepix family with high-voltage post-acceleration
capabilities. The mass spectral and imaging performance of the system is tested
with various benchmark samples and thin tissue sections. We show that the high
secondary ion yield (with respect to traditional monatomic primary ion sources)
of the C60 primary ion source and the increased sensitivity of the high voltage
detector setup improve microscope mode secondary ion mass spectrometry imaging.
The analysis time and the signal-to-noise ratio are improved compared to other
microscope mode imaging systems, all at high spatial resolution. We have
demonstrated the unique capabilities of a C60 ion microscope with a Timepix
detector for high spatial resolution microscope mode secondary ion mass
spectrometry imaging.
