Ion microscopy with GaBiLi for FIB imaging, 3D analysis, and nanoscale tomography

Utilize GaBiLi - the FIB source containing Gallium, Bismuth and Lithium - for high-resolution ion microscopy

GaBiLi is a multipurpose ion source for FIB-SEM applications which covers:

  • ion microscopy and
  • 3D sample tomography, as well as
  • nanofabrication.

Ions from liquid metal alloy ion sources (LMAIS) can be used in nanofabrication for commencing smart patterning strategies. The individual characteristics of light or heavy ions that are simultaneously emitted from a single source with a subsequent ExB mass separation filter can be utilized.

Learn more about the LMAIS in the IONselect Whitepaper

Focused ion beam microscopy with highest resolution

At the same time, a FIB with a GaBiLi source can be used for ion microscopy and 3D sample analysis for reconstruction at the nanoscale. Beside the heavy ions gallium and bismuth, GaBiLi contains lithium as the lightest ion available for LMAIS, which is very suitable for FIB imaging. Lithium follows helium in the periodic table. It enables ion microscopy to acquire high resolution 2D ion images. Lithium has excellent ion microscopy capabilities at highest lateral resolution from all elements that are suitable for Focused Ion Beams from LMAIS.

As with a helium ion microscope, images acquired with a FIB microscope using lithium allow low-damage characterization of the sample. Lithium ions have the lowest energy spread and virtual source diameter of all ions available from LMAIS.

Lithium ion image of grafite
Lithium ion image of graphite
Lithium ion image of tin balls on carbon substrate

Lithium ion images of graphite and of tin balls on carbon substrate

Combining an ion microscope with precise, easy, and efficient milling

The VELION FIB-SEM system enables FIB imaging to be performed with various ion species including lithium. Due to its unique setup with a vertically mounted FIB column, the ion beam of either lithium, gallium, or bismuth is always perpendicular to the sample surface. IONselect offers the ability to change ions reliable and quickly without sample tilt.

In this way, the sample can be milled and imaged in the same tool and without a curtaining effect. Bi, Ga, and Li beams can be switched instantly and automatically, and are subsequently applied to the sample either for milling with heavy bismuth or gallium ions, or for light-ion microscopy with lithium. 3D nanoscale tomography becomes possible at unrivaled stability and fidelity.

Ions from liquid metal alloy ion sources (LMAIS) can be used in nanofabrication for commencing smart patterning strategies. Individual characteristics of light or heavy ions that are simultaneously emitted from a single source with a subsequent ExB mass separation filter can be utilized.

Appropriate Bi beam milling strategies are effectively employed to ensure smooth and uniform delayering of the sample when digging into the substrate. Intermittent scanning ion microscopy with lithium delivers high-resolution images between respective milling steps, which can than be combined for a 3D nano-reconstruction of the sample.

Depth resolution and surface smoothness can be designed by choosing from gallium or bismuth ions or Bi cluster for milling. On top of that, the precision of the laser interferometer stage enables the single images to be stacked accurately since the absolute position of each pixel is known. It is therefore possible to create high-precision 3D models of the sample.

A workflow alternately using bismuth ions for fast sample delayering and lithium for imaging can be combined with the precision of a laser interferometer stage to result in a powerful ion microscope for 3D imaging.

For more information about the VELION FIB-SEM system with ion microscopy capabilities, visit the VELION product site. Should you have any further questions, please do not hesitate to get in touch.