Scanning surfaces using a beam of noncharged atoms or molecules allows for especially nondestructive and low-energy surface imaging, with the potential to obtain new information about surfaces that cannot be easily obtained otherwise. We have developed a new approach, operating with the sample at a close working distance from an aperture, the need for optics to focus the beam is obviated. Compared to more complex approaches, the theoretical performance has no other disadvantage than the short working distance. Resolution of 1.5 μm has been achieved, and submicron resolution appears to be practical. Construction of the microscope and results are presented, including first images done in reflection mode, theory for optimization of the design and avenues for future improvement.

A new imaging method known as Neutral Atom Microscopy (NAM) or Scanning Helium Microscopy promises to open a unique window to the nature of surfaces at the first atomic layer. The thermal energy, non-charged beam of atoms used allows exploring samples without the destructive effects of energetic particles or electric charges, in addition to having no topographic limitations due to the aspect ratio or shape of a solid probe tip, and with resolution potentially far better than conventional far-field optical microscopes. Contrast mechanisms which produce surface composition information have long been known from atomic scattering experiments, such as by atomic diffraction from crystal surfaces or contrast due to surface roughness. These are now being explored in images for the first time.

Summary The neutral atom microscope uses a beam of thermal noncharged atoms or molecules to probe an atomic surface with very low interaction energies (<70 meV). Continued optimization of the ‘pinhole’ neutral atom microscope has improved resolution to 0.35 μm. Recent images are presented demonstrating resolution and the contrast mechanisms identified so far. The future potential for sub‐100 nm resolution is discussed.

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