Electron Optic Documents

SEM is an indispensable tool for studying the microstructure of a wide variety of materials. The images generated are inherently a 2 dimensional representation of the sample surface. Unlocking the 3rd dimension by reconstructing a 3D model from multiple SEM images can enhance our understanding of complex microstructure. This 3D view is often more intuitive and surface metrology characteristics can be calculated.

In this interview, AZoM speaks to Vern Robertson, EPMA Product Manager at JEOL USA, about the benefits of using a low kV in SEM imaging.

JEOL is always making efforts to meet the needs of our customers in all areas including hardware and software of our instruments. Our efforts to grasp customer requirements include question and answer opportunities during technical seminars and meetings. Based on these questions, we have published this Q&A book.

What makes the difference between a good SEM image and a stellar one? Imaging samples at the appropriate conditions, and that often means at very low accelerating voltage (low kV). It's time to give it a try! Every modern day scanning electron microscope (SEM) from the top of the line, ultra-high resolution field emission SEMs to the most economical entry level bench-top tungsten (W) thermionic SEMs have the capability of imaging samples at very low accelerating voltage (Low kV ). Low kV imaging has many benefits and this easily accessible function should not be overlooked.

Effortless sample navigation using JEOL’s Stage Navigation System (SNS). This system includes a high resolution, color CMOS camera mounted on the top of the SEM sample chamber, which captures a picture of the sample mounted on the stage. From this color picture, the user can control the position of the sample.

STEM-in-SEM (Scanning Transmission Electron Microscopy in an SEM) has become a popular technique for biologists, polymer scientists and materials scientists for its ease of use, cost effectiveness and high resolution. It is especially suited to investigating the internal structure of thin film (100-200nm) samples as well as size and shape of submicron to nanometer particles. With standard SEM imaging modes on bulk samples, there are limitations in the ultimate resolution that can be achieved due in part by the beam-sample interactions. With STEM-in-SEM, the sample is very thin and the interaction volume is small. Therefore, the resolution more closely approximates the diameter of the electron beam at the exit surface of the sample allowing for high resolution; using STEM with our state of the art FE SEMs, sub-nanometer resolution is easily achieved.

STEM-in-SEM (Scanning Transmission Electron Microscopy in an SEM) has become a popular technique for biologists, polymer scientists and materials scientists for its ease of use, cost effectiveness and high resolution. It is especially suited to investigating the internal structure of thin film (100-200nm) samples as well as size and shape of submicron to nanometer particles. With standard SEM imaging modes on bulk samples, there are limitations in the ultimate resolution that can be achieved due in part by the beam-sample interactions. With STEM-in-SEM, the sample is very thin and the interaction volume is small. Therefore, the resolution more closely approximates the diameter of the electron beam at the exit surface of the sample allowing for high resolution; using STEM with our state of the art FE SEMs, sub-nanometer resolution is easily achieved.

JEOL’s Three Dimensional Image Software is a program that takes stereo pair SEM images and constructs a three dimensional (3D) image of the sample surface. From this 3D image, height and contour maps can be created to provide cross sectional shape and height data. The easiest approach to creating stereo pair images is to take two images of the same area but at different tilt angles. Images can be taken with any detector, at any magnification, with high or low accelerating voltage and even in low vacuum mode. With this software, any offset to the stereo pair images can be corrected for automatically and an anaglyph image or 3D model of the surface created.

The Tilt Rotation Motor Drive Holder (TRMH) is a motorized specimen holder designed for the JCM-7000, NeoScope™. This holder provides tilt and rotation capability during image observation. Installing this holder allows for 4 axis motor control.

Imaging of nanostructured materials requires a new design of SEM that provides ultimate resolution for both imaging and microanalysis, combined with the ability to image any type of material. An innovative new SEM column design from JEOL Ltd. utilizes a hybrid lens (combination electrostatic and electromagnetic lenses) in conjunction with a Through-The-Lens (TTL) detection system to provide the user with ultimate imaging and analytical performance. The hybrid electrostatic/electromagnetic lens minimizes magnetic field effects at the sample and is relatively impervious to stray magnetic fields. The lens is characterized by low values for the spherical and chromatic aberration coefficients. Moreover, the proven Aberration Correction Lens (ACL) technology automatically maintains small probe size for both imaging and microanalysis.