Ion microscopy

Abstract

Helium ion microscopy (helium ion microscopy (HIM)) is a relatively young imaging and nanofabrication technique, which is based on a gas field ion source (GFIS). It rasters a narrow beam of helium ions across the surface of the specimen, to obtain high-resolution surface-sensitive images. Usually, secondary particles such as electrons are collected for image formation but also photons, backscattered atoms or sputtered sample atoms can be used for image formation. Thanks to the very high brightness of the source, a lateral resolution of 0.5nm can be achieved. The method is in particular suitable for obtaining high-resolution images of insulating samples (such as ceramic materials and biological samples) as the built-in charge compensation allows us to observe such specimens without any additional conductive coatings. In this chapter, I will introduce the method and briefly sketch the underlying physics. In the remainder of the chapter, a number of imaging modes will be discussed and selected examples will be presented. Finally, an outlook is presented on the ongoing efforts to add analytical capabilities to the method.