The helium ion microscope: a new tool for nanomanufacturing

Abstract

Helium Ion Microscopy (HIM) is a new, potentially disruptive technology for nanotechnology and nanomanufacturing. This methodology presents a potentially revolutionary approach to imaging and measurements which has several potential advantages over the traditional scanning electron microscope (SEM) currently in use in research and manufacturing facilities across the world. Due to the very high source brightness, and the shorter wavelength of the helium ions, it is theoretically possible to focus the ion beam into a smaller probe size relative to that of an electron beam of an SEM. Hence higher resolution is theoretically possible. In an SEM, an electron beam interacts with the sample and an array of signals are generated, collected and imaged. This interaction zone may be quite large depending upon the accelerating voltage and materials involved. Conversely, the helium ion beam interacts with the sample, but it does not have as large an excitation volume and thus the image collected is more surface sensitive and can potentially provide sharp images on a wide range of materials. The current suite of HIM detectors can provide topographic, material, crystallographic, and electrical properties of the sample. Compared to an SEM, the secondary electron yield is quite high - allowing for imaging at extremely low beam currents and the relatively low mass of the helium ion, in contrast to other ion sources such as gallium results in no discernable damage to the sample. This presentation will report on some of the preliminary work being done on the HIM as a research and measurement tool for nanotechnology and nanomanufacturing at NIST.