New review highlights correlative microscopy methodology that combines imaging modalities

As more and more electronic devices use nanoscale components and require finely tuned dopant distributions, techniques for high-resolution structural imaging and dopant mapping have come in increasing demand. While transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) each offers part of these capabilities, a technique that can adequately address the analytical challenges has been elusive.

Eswara et al. review the capabilities of a new correlative microscopy methodology capable of providing high-resolution structural imaging and chemical mapping by combining TEM and SIMS images. The paper highlights key strengths and drawbacks of the technique, known as Parallel Ion Electron Spectrometry (PIES), which makes both modes of imaging quickly in a single in situ instrument.

The group has surveyed how the PIES technique can be applied to broad range of uses that draw on the advantages of both modalities, including selectively identifying and imaging nanoparticles of certain lithium isotopes, as well as assessing solar cells by mapping hydrogen.

Combining such techniques has the potential to eliminate the cumbersome need to transfer samples, which helps avoid artifacts caused when samples are exposed to the air during measurements.

Looking forward, the group expects to further improve the arsenal of nano-analytical methods to address important characterization challenges in the development of high-tech materials. They hope it will inspire others to combine other modalities for novel approaches.

“The new in situ correlative methodology we present here adds a powerful characterization capability to researchers across nearly all branches of physical sciences and beyond,” said Santhana Eswara, an author on the paper.

Source: “Correlative microscopy combining transmission electron microscopy and secondary ion mass spectrometry: A general review on the state-of-the-art, recent developments and prospects,” by S. Eswara, A. Pshenova, L. Yedra, Q. H. Hoang, J. Lovric, P. Philip, and T. Wirtz, Applied Physics Reviews (2019). The article can be accessed at https://doi.org/10.1063/1.5064768 .