Overview

General Description

The ORION NanoFab uses a beam of helium ions, produced from a proprietary gas field ion source (GFIS), which is focused and scanned across the sample. The source technology, the sample interaction, and the contrast mechanisms are distinctly different from the traditional scanning electron microscope (SEM). The helium ion offers high brightness and a small energy spread, and hence allows the beam to be focused to small probe sizes. The ion beams can be precisely controlled with variable energy, variable beam currents, and with steering to achieve sub- nanometer beam positioning with sub-microsecond timing. As the beam interacts with the sample, the beam penetrates relatively deeply before it diverges and hence there is a narrow sample interaction region near the surface. The helium beam generates secondary electrons, scattered helium atoms (ions and neutrals), and other detectable particles from which images can be generated or analysis can be performed.

This tool offers a tremendous range of new capabilities, from imaging, to analysis, to nanofabrication and to characterization. The high brightness, highly focused ion beams have only recently been available, and as such offer many new possibilities for usage in a wide range of applications.
In short, the NanoFab serves as the operator’s “eyes and hands” at the nanoscale. As “eyes”, the ion beams generate images with incredibly high resolution. Depending on the sample and the imaging conditions, the images can reveal information through a range of contrast mechanisms that can include topography, compositional differences, crystal grains, and voltage contrast.
In addition to imaging, the NanoFab can be used at higher dosages as “hands” in the nanoworld; that is, tools to modify and manipulate samples. For example, the ion beam’s sputtering process can create precision cuts and drilled holes that are smaller than 5 nm. With the addition of gas phase precursors, the ion beam can be used as a nanoscale pen, to deposit either conductive or insulating materials with an arbitrary pattern and with features as small as 10 nm. Lighter ion beams can also be used to expose negative tone (or positive tone) resists to change their properties so that only the exposed (or un-exposed) regions persist after the development process. Ion beams can also be used to implant dislocations into a material with an otherwise orderly atomic structure and correspondingly change the physical properties in the prescribed area.
In short, the NanoFab’s ion beams can serve as versatile tools for manipulating matter on the nanometer scale.

Specifications

Technology Overview

Sample Requirements and Preparation

Standard Operating Procedure

Questions & Troubleshooting

Process Library

References

CalTech: ORION NanoFab: Helium, Neon & Gallium FIB