  Time of flight backscattering spectrometry (ToF-BS) was successfully
implemented in a helium ion microscope (HIM). Its integration introduces the
ability to perform laterally resolved elemental analysis as well as elemental
depth profiling on the nm scale. A lateral resolution of $\leq$ 54 nm and a
time resolution of $\Delta t \leq$ 17 ns $(\Delta t/t \leq 5.4\%)$ are
achieved. By using the energy of the backscattered particles for contrast
generation, we introduce a new imaging method to the HIM allowing direct
elemental mapping as well as local spectrometry. In addition laterally resolved
time of flight secondary ion mass spectrometry (ToF-SIMS) can be performed with
the same setup. Time of flight is implemented by pulsing the primary ion beam.
This is achieved in a cost effective and minimal invasive way that does not
influence the high resolution capabilities of the microscope when operating in
standard secondary electron (SE) imaging mode. This technique can thus be
easily adapted to existing devices. The particular implementation of ToF-BS and
ToF-SIMS techniques are described, results are presented and advantages,
difficulties and limitations of this new techniques are discussed.
