Topic: electrons

Electron lenses and aberrations: what affects the resolution in electron microscopes?

By Marijke Scotuzzi - Aug 30, 2018

Resolution is one of the most important parameters in a scanning electron microscope (SEM). The lower the resolution, the smaller the features that can be seen. The resolution, which is typically not defined (and therefore measured) in a unique way, depends on the size of the beam when focused on the sample.

Resolution is one of the most important parameters in a scanning electron microscope (SEM). The lower the resolution, the smaller the features that can be seen. The resolution, which is typically not defined (and therefore measured) in a unique way, depends on the size of the beam when focused on the sample.

Read more

SEM technology: the role of the electron beam voltage in electron microscopy analysis

By Luigi Raspolini - Jul 6, 2018

When conducting electron microscopy (EM) analysis, there are a few important parameters that must be taken into account to produce the best possible results, and to image the feature of interest. One of the crucial roles is played by the voltage (or tension) applied to the source electrodes to generate the electron beam. Historically, the trend has always been to increase the voltage to improve the resolution of the system.

It is only in recent years that scanning electron microscope (SEM) producers have started to focus on improving the resolution at lower voltages. A major role in this has been the expanding field of application of EM to the life sciences - especially after the introduction of the Nobel prize-winning cryo-SEM technique. This blog will focus on the effects of the voltage on the results of electron microscopy analysis.


When conducting electron microscopy (EM) analysis, there are a few important parameters that must be taken into account to produce the best possible results, and to image the feature of interest. One of the crucial roles is played by the voltage (or tension) applied to the source electrodes to generate the electron beam. Historically, the trend has always been to increase the voltage to improve the resolution of the system.

It is only in recent years that scanning electron microscope (SEM) producers have started to focus on improving the resolution at lower voltages. A major role in this has been the expanding field of application of EM to the life sciences - especially after the introduction of the Nobel prize-winning cryo-SEM technique. This blog will focus on the effects of the voltage on the results of electron microscopy analysis.


Read more

EDX analysis with a scanning electron microscope (SEM): how does it work?

By Antonis Nanakoudis - Jun 21, 2018

Scanning electron microscopes (SEMs) employ electron beams in order to get information from a sample at the nanoscale. The main type of signals that are detected are the backscattered (BSE) and secondary electrons (SE), which generate a grayscale image of the sample at very high magnifications. However, there are many other signals which can be a product of the electron-matter interaction, and these can provide additional information about the sample. In this blog we will describe how energy-dispersive X-ray (EDX or EDS) analysis works on a SEM.

Scanning electron microscopes (SEMs) employ electron beams in order to get information from a sample at the nanoscale. The main type of signals that are detected are the backscattered (BSE) and secondary electrons (SE), which generate a grayscale image of the sample at very high magnifications. However, there are many other signals which can be a product of the electron-matter interaction, and these can provide additional information about the sample. In this blog we will describe how energy-dispersive X-ray (EDX or EDS) analysis works on a SEM.

Read more

SEM working principle: the detection of backscattered electrons

By Marijke Scotuzzi - Jun 14, 2018

Backscattered electrons (BSEs) are high-energy electrons that are produced by the elastic scattering of the primary beam electrons with the atom nuclei. The yield of BSEs, that is the ratio of the number of emitted BSEs and the amount of primary beam electrons, depends on the atomic number: the higher the atomic number, or the heavier the element, the brighter the contrast. In the Phenom SEM, BSEs are detected using four-quadrant semiconductor detectors placed above the sample. In this blog, we will explain what a semiconductor detector is and how backscattered electrons are detected in a scanning electron microscope.

Backscattered electrons (BSEs) are high-energy electrons that are produced by the elastic scattering of the primary beam electrons with the atom nuclei. The yield of BSEs, that is the ratio of the number of emitted BSEs and the amount of primary beam electrons, depends on the atomic number: the higher the atomic number, or the heavier the element, the brighter the contrast. In the Phenom SEM, BSEs are detected using four-quadrant semiconductor detectors placed above the sample. In this blog, we will explain what a semiconductor detector is and how backscattered electrons are detected in a scanning electron microscope.

Read more

What is SEM? Scanning electron microscope technology explained

By Antonis Nanakoudis - Jun 7, 2018

Scanning electron microscopy (SEM) has become a powerful and versatile tool for material characterization. This is especially so in recent years, due to the continuous shrinking of the dimension of materials used in various applications. In this blog, we explain what SEM is and describe the main working principles of a SEM instrument.

Scanning electron microscopy (SEM) has become a powerful and versatile tool for material characterization. This is especially so in recent years, due to the continuous shrinking of the dimension of materials used in various applications. In this blog, we explain what SEM is and describe the main working principles of a SEM instrument.

Read more

SEM and TEM: what's the difference?

By Antonis Nanakoudis - Feb 8, 2018

Electron microscopes have emerged as a powerful tool for the characterization of a wide range of materials. Their versatility and extremely high spatial resolution render them a very valuable tool for many applications. The two main types of electron microscopes are the Transmission Electron Microscope (TEM) and the Scanning Electron Microscope (SEM). In this blog we briefly describe their similarities and differences.

Electron microscopes have emerged as a powerful tool for the characterization of a wide range of materials. Their versatility and extremely high spatial resolution render them a very valuable tool for many applications. The two main types of electron microscopes are the Transmission Electron Microscope (TEM) and the Scanning Electron Microscope (SEM). In this blog we briefly describe their similarities and differences.

Read more

Inside a scanning electron microscope: the SEM electron column explained

By Marijke Scotuzzi - Dec 21, 2017

Scanning electron microscopes (SEMs) use an electron beam to image samples with a resolution down to the nanometer scale. The electrons are emitted from a filament and collimated into a beam in the electron source. The beam is then focused on the sample surface by a set of lenses in the electron column. How does an electron lens work? And which kind of lenses exist? How are lenses combined to form an electron column? In this blog, we will answer these questions and give a general insight into the working principle of an electron column.

Scanning electron microscopes (SEMs) use an electron beam to image samples with a resolution down to the nanometer scale. The electrons are emitted from a filament and collimated into a beam in the electron source. The beam is then focused on the sample surface by a set of lenses in the electron column. How does an electron lens work? And which kind of lenses exist? How are lenses combined to form an electron column? In this blog, we will answer these questions and give a general insight into the working principle of an electron column.

Read more

Desktop SEM electron sources: why CeB6 is the right choice

By Karl Kersten - Aug 3, 2017

If you’re looking for a scanning electron microscope (SEM), you probably know by now that the electron source is one of the most important parts of the system. In a previous blog, we talked about the properties of three different electron sources: the Tungsten, CeB6 and FEG sourcesIn this blog, we’ll take a closer look at Tungsten and CeB6 electron sources.

If you’re looking for a scanning electron microscope (SEM), you probably know by now that the electron source is one of the most important parts of the system. In a previous blog, we talked about the properties of three different electron sources: the Tungsten, CeB6 and FEG sourcesIn this blog, we’ll take a closer look at Tungsten and CeB6 electron sources.

Read more

SEM: types of electrons, their detection and the information they provide

By Antonis Nanakoudis - Jun 29, 2017

Electron microscopes are very versatile instruments, which can provide different types of information depending on the user’s needs. In this blog we will describe the different types of electrons that are produced in a SEM, how they are detected and the type of information that they can provide.

Tip: Get a free demo of our Desktop SEM and discover it's capabilities for your research
Request your personal demo

Electron microscopes are very versatile instruments, which can provide different types of information depending on the user’s needs. In this blog we will describe the different types of electrons that are produced in a SEM, how they are detected and the type of information that they can provide.

Tip: Get a free demo of our Desktop SEM and discover it's capabilities for your research
Request your personal demo

Read more

Press Room | Privacy Policy | Terms of Use | Sitemap