Low Voltage Electron Microscopy: Principles and Applications

Chapter 4

The Application of Low-Voltage SEM—From Nanotechnology to Biological Research

Natasha Erdman¹ and David C. Bell²

¹JEOL USA Inc., USA

²School of Engineering and Applied Sciences, Harvard University, USA

4.1 Introduction

The idea behind nanotechnology is simple: exploit the properties of the nanoscale for the macroscopic world in which we live. Historically, nanomaterials have been with us a long time we just didn't know them as such. The discovery of various nanomaterials was only made possible by electron microscope observation. Although the attribution of who was first remains a debated issue, Sumio Iijima's report in 1991 (Iijima, 1991) is important because it brought carbon nanostructures to the awareness of the whole community. The ability to image carbon, a low atomic number material, is after all an impressive feat, which has led to the imaging of fullerenes and most importantly graphene, which has a potential to become “the new silicon” for future electronics devices. Microscopy has played an integral role in characterization of nanomaterials, and often provides invaluable insight into the structure-properties relationship.

In the last decade there has been a quantum leap in the ability of the SEM to observe nanomaterials with ultra-high resolution and exceptional surface detail, in particular employing low-voltage SEM. Improvements in objective lens optics with smaller chromatic and spherical aberration coefficients, ability to deal with charging specimens via ...