Scanning Helium Ion Microscope

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A Scanning Helium Ion Microscope (SHIM) is a new imaging technology based on a scanning helium ion beam.^[1] This technology has several advantages over the traditional SEM. Due to the very high source brightness, and the short (De Broglie) wavelength of the helium ions, it is possible to obtain qualitative data not achievable with conventional microscopes using basic particles (photons, electrons,..) as the emitting source. As the He-ion beam interacts with the sample, it does not suffer from a large excitation volume, and hence provides sharp images on a wide range of materials. Compared to a SEM, the secondary electron yield is quite high - allowing for imaging with currents as low as 1 femtoamp. The detectors provide information-rich images which offer topographic, material, crystallographic, and electrical properties of the sample. In contrast to other ion beams, there is no discernible sample damage due to relatively light mass of the helium ion. Sample images will be presented.

A tenfold increase in resolution is expected and the ability to observe things smaller than have ever been seen with even the most sophisticated scanning/transmission electron (S/TEM) microscope. Magnification up to one million times is expected. Apparently the technology is near commercialization.^[2]

SHeMs (microscopes) are commercialized, whilst imaging with neutral atoms such as Helium atoms, is much more complicated and has only recently found commercial products introduced.