Helium Ion Microscope Supplements SEMs

摘要

The helium ion microscope (HIM), introduced by ALIS Corp. (Peabody, Mass.), promises to supplement some of the traditional SEM's shortcomings. In a common SEM, the probe size is limited principally by two conditions. The first is diffraction, attributed to the electron's non-zero de Broglie wavelength. As electrons stream through an aperture, they diverge, resulting in a larger probe size. A larger aperture moderates the diffraction effect, but results in an increase in the chromatic aberration, the second negative effect.