JEOL Resourceshttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-DownloadsA Note on Magnificationhttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/a-note-on-magnificationIT200Mon, 02 Nov 2020 12:04:09 GMTSEM manufacturers can choose different output sizes for their images, making magnification a very deceptive number when comparing SEM micrographs from different SEM manufacturers. Because of this fact, the best way to compare images is to compare the length of the micron bar or field of view.<h4>JEOL Technical Note</h4> <p>Magnification is defined as the ratio of the size of the rastered area on the sample to the size of the rastered area of the output, as is shown in Figure 1. Traditionally, the output size was defined as a Polaroid 4x5 film size by all vendors and results were easy to compare. However, since images are now collected digitally and can be output at various sizes, this “output size” is ill-defined. SEM manufacturers can choose different output sizes for their images, making magnification a very deceptive number when comparing SEM micrographs from different SEM manufacturers. Because of this fact, the best way to compare images is to compare the length of the micron bar or field of view.</p> <p class="caption" style="text-align: center;"><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/A%20Note%20on%20Magnification%20fig1.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=qwBAKbK5vdFXBnMuqKvDTHaPuWU%3D" /><br /> <strong>Figure 1</strong>: A small raster on the specimen leads to a large magnification for the same output size.</p> <p>The SEM images of hematite from two different SEM manufacturers below illustrate this point. The left image is from a JEOL SEM and has a magnification labeled as 75,000 X with a 100 nm micron bar. The right image is from another SEM manufacturer and has a magnification labeled as 150,000 X with the exact same length 100 nm scale bar (highlighted in red). This shows that the enlargement of the sample is identical in the two images, even though the magnification value stated by the other SEM manufacturer is twice that of the JEOL image.</p> <p class="caption" style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/A%20Note%20on%20Magnification%20fig2.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=ee9XnW4z%2FNODAGjnIrjYn%2B%2Bz9%2Fg%3D" /><br /> <strong>Figure 2</strong>: SEM images of hematite with the same enlargement of the sample despite having different magnification values stated. Left image: From a JEOL SEM Right image: From a different SEM manufacturer</p> Air Isolated Transfer Systemhttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/air-isolated-transfer-systemIT200Mon, 02 Nov 2020 12:16:34 GMTThere are a number of applications where scientists and engineers are faced with air or moisture sensitive samples that require imaging and analysis using a scanning electron microscope (SEM). Applications include: components in rechargeable batteries, fuel cells, and catalysts among others. Any exposure to oxygen or moisture in the air can completely alter or destroy the structure of these highly reactive materials. JEOL has built a special air-lock system that can handle the transfer of air-sensitive specimens to be imaged in the SEM without atmospheric exposure.<h4>Latest Innovation in our FE SEMs</h4> <h3>SMART – POWERFUL – FLEXIBLE</h3> <p>There are a number of applications where scientists and engineers are faced with air or moisture sensitive samples that require imaging and analysis using a scanning electron microscope (SEM). Applications include: components in rechargeable batteries, fuel cells, and catalysts among others. Any exposure to oxygen or moisture in the air can completely alter or destroy the structure of these highly reactive materials. JEOL has built a special air-lock system that can handle the transfer of air-sensitive specimens to be imaged in the SEM without atmospheric exposure.</p> <p class="caption" style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air%20Isolated%20Transfer%20System%201.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=xkpdwzMtMpoQzXu0bEdfuNq5TUI%3D" /><br /> The sample can be prepared, mounted on the holder, and covered with a cap while inside a glove box. The cap seals and isolates the sample from the environment.</p> <p class="caption" style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air%20Isolated%20Transfer%20System%202.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=pNIu1zuAhMeq0w%2FJQiRX3%2Bm9R%2Fg%3D" /><br /> The sample holder (w/cap) is then removed from the glovebox and transferred into the load lock of the SEM. After the airlock is evacuated, the user can open the cap and put the sample into the FE-SEM without air exposure.</p> Aperture Angle Control Lenshttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/aperture-angle-control-lensIT800Mon, 02 Nov 2020 12:32:11 GMTThe ability to increase the probe current for fast microanalysis, while still maintaining a small spot size and small volume of excitation for high resolution, has been the holy grail of microanalysis in SEM. One of the unique features of JEOL’s FE-SEMs is the patented Aperture Angle Control Lens (ACL). This lens automatically optimizes for both high resolution imaging at low probe currents and high spatial resolution X-ray analysis at high probe currents with a seamless transition between the two.<h4>JEOL FE-SEM – Innovative Design</h4> <h3>SMART – POWERFUL – FLEXIBLE</h3> <p>The ability to increase the probe current for fast microanalysis, while still maintaining a small spot size and small volume of excitation for high resolution, has been the holy grail of microanalysis in SEM. One of the unique features of JEOL’s FE-SEMs is the patented Aperture Angle Control Lens (ACL). This lens automatically optimizes for both high resolution imaging at low probe currents and high spatial resolution X-ray analysis at high probe currents with a seamless transition between the two. This is essential for rapid analysis and optimized image quality and is particularly true for low kV microanalysis. The ACL works by taking into account effects of all aberrations (such as spherical aberration and diffraction limitations) on spot size and optimizing the convergence angle accordingly in an automatic fashion.</p> <p class="caption" style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Aperture%20Angle%20Control%20Lens%201.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=56JfhP6Ry9Li%2BZMAxfH0O2aEtG0%3D" /><br /> <strong>Figure 1</strong>: Beam current density on a Gaussian plane. ACL optimization at high beam currents for (a) image resolution, and (b) analytical resolution. Nano gold images and EDS analysis completed at 5 kV, 20kX, and 73 nA.</p> <p>When the SEM is optimized for the smallest spot size (largest convergence angle) there is some beam tailing that produces X-rays from areas “not in the spot”. For low beam current applications this is insignificant. The best analytical data comes from the smallest convergence angle. Therefore, when the ACL is optimized for image resolution, the resulting high current image (large convergence angle) has somewhat ‘hazy’ background but shows great resolution. However, when the ACL is optimized for analytical work the ultimate resolution is slightly decreased, yet the analytical signal is no longer affected by the beam tailing resulting in smaller analytical signal delocalization (Figure 1).</p> <p>The automatic optimization of the ACL maintains high resolution imaging at a wide range of accelerating voltages and probe currents, from a few picoamps to hundreds of nanoamps. This beam resolution allows very fast acquisition (using high beam current) of EDS or WDS data at low kV with high spatial resolution.</p> <p class="caption" style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Aperture%20Angle%20Control%20Lens%202.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=akuyudLp3M6XMnDLaIedPWu%2BDMo%3D" /><br /> <strong>Figure 2</strong>: EDS map of nickel pillars on ITO which has sub-25nm resolution. The map was taken at 8kV with 5 nA of beam current.</p> <p>Implementation of the ACL function allows collection of very fast EDS maps at high spatial resolution using low kVs. One such example is shown in Figure 2. This is an EDS map of nickel pillars on ITO with sub-25nm resolution. The map was collected at 8 kV using a beam current of 5 nA.</p> <p>The ability to deliver high beam current also impacts WDS and CL (cathodoluminescence) analyses where large beam currents are needed for sufficient signal to noise collection. In the JEOL FE-SEMs, the ability of the ACL to keep the spot size small when the beam current is high results in efficient WDS mapping with high spatial resolution even at lower kV's. This is also true for CL analysis – high spatial resolution of CL collection requires a combination of high current/low voltage/small spot size.</p> <p>Shown in Figure 3 is an example of slip planes in diamond imaged with panchromatic KE Centaurus CL detector at 2 kV.</p> <p class="caption" style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Aperture%20Angle%20Control%20Lens%203.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=JKMVFD18wtaeusdXwPVsfM6TAwY%3D" /><br /> <strong>Figure 3</strong>: CL image of diamond grains collected with KE Centaurus CL.</p> Automated Imaging Solutions for SEMhttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/automated-imaging-solutions-for-semIT500Wed, 03 Jan 2024 16:50:43 GMTJEOL now offers both simple and advanced automation solutions, giving users the capability to develop protocols that fit their exact imaging needs. When paired with best-in- class AI-driven auto-function technology (auto focus, auto astigmatism correction, auto brightness/contrast), JEOL’s automation solutions are fast, reliable, reproducible, and applicable to a wide range of applications.<p>Automation of routine imaging in Scanning Electron Microscopy (SEM) has gained significant popularity over recent years. Automation provides users with additional levels of flexibility, including unattended and remote operation, as well as repeatability of their measurements. This ability maximizes productivity and sample throughput and significantly lowers the level of expertise required to proficiently operate SEMs. JEOL now offers both simple and advanced automation solutions, giving users the capability to develop protocols that fit their exact imaging needs. When paired with best-in- class AI-driven auto-function technology (auto focus, auto astigmatism correction, auto brightness/contrast), JEOL’s automation solutions are fast, reliable, reproducible, and applicable to a wide range of applications.</p> <h2>Simple Automation with Simple SEM</h2> <p>Simple SEM, JEOL’s latest advancement in automated imaging solutions, is a fully-integrated interface for creating and implementing imaging routines (Figure 1) without the need for programing experience. Users have the ability to develop custom automated workflows, including acquisition of SEM images and EDS data at a series of magnifications and locations on the sample surface and with varying operating conditions (accelerating voltage, probe current). Simply checking a box enables JEOL’s best-in-class auto-functions, with the added flexibility to control how often these functions are utilized within the workflow. Once routines are created, they are automatically saved and can be quickly implemented by simply selecting the area(s) on the sample that the user wants to characterize directly from a live image or ZeroMag view.</p> <p>Simple SEM is available as part of the standard software package on JEOL’s JSM-IT210, JSM-IT510 and JSM-IT710 SEM models.</p> <p style="text-align: center;"><img alt="Figure 1. Simple SEM is fully integrated within JEOL’s SEM control software, creating an intuitive environment for users to develop automation workflows without any need for programing experience." src="https://jeolusa.s3.amazonaws.com/resources_eo/Automated%20Imaging%20Solutions%20for%20SEM%2001.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=u5liPJoFw7B3RHGeMBBkk4ASV%2FA%3D" /><br /> <strong>Figure 1.</strong> Simple SEM is fully integrated within JEOL’s SEM control software, creating an intuitive environment for users to develop automation workflows without any need for programing experience.</p> <p><strong>Compatible Instruments:</strong> JSM-IT210, JSM-IT510, JSM-IT710HR<br /> <strong>Options:</strong> integration with JEOL EDS</p> <h2>Advanced Automation with Python and C#</h2> <p>For customers with more unique or challenging imaging demands, JEOL continues offers advanced external SEM control using Python or C# (Figure 2). This gives users the flexibility to fully develop and customize imaging protocols and interfaces, optimize acquisition at any operating conditions, automate image processing, and even integrate machine learning (Figure 3).</p> <p style="text-align: center;"><img alt="Figure 2. JEOL offers full external microscope control using Python and C#, allowing users to develop custom interfaces and automation programs. A full library of functions is available upon request." src="https://jeolusa.s3.amazonaws.com/resources_eo/Automated%20Imaging%20Solutions%20for%20SEM%2002.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=0xg%2FOlL0MI8DNbF6BFEiq3Iw1Pw%3D" /><br /> <strong>Figure 2.</strong> JEOL offers full external microscope control using Python and C#, allowing users to develop custom interfaces and automation programs. A full library of functions is available upon request.</p> <p style="text-align: center;"><img alt="Figure 3. External control allows users to develop custom interfaces and programs and integrate complex automation routines." src="https://jeolusa.s3.amazonaws.com/resources_eo/Automated%20Imaging%20Solutions%20for%20SEM%2003.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=B7phd2jhNxYfnxUBgKf%2FwClFhsc%3D" /><br /> <strong>Figure 3.</strong> External control allows users to develop custom interfaces and programs and integrate complex automation routines.</p> <p><em>External control with Python (3.5.1 or later) and C# available with all current JEOL SEM models. Additional compatible SEM models are available upon request.</em></p> Can I Trust My Quantitative EDS Data?https://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/can-i-trust-my-quantitative-eds-dataIT200Mon, 02 Nov 2020 17:48:37 GMTScanning electron microscopes (SEM) coupled with an energy dispersive X-ray detector (EDS) are used extensively to provide insight into a sample’s chemical makeup. This SEM-EDS technique can provide information on the elements present, their relative concentrations and spatial distribution over very small volumes (micron and some instances nanometer scale).<p>NOTES ON STANDARDLESS QUANTITATIVE EDS IN SEM</p> <p>Scanning electron microscopes (SEM) coupled with an energy dispersive X-ray detector (EDS) are used extensively to provide insight into a sample’s chemical makeup. This SEM-EDS technique can provide information on the elements present, their relative concentrations and spatial distribution over very small volumes (micron and some instances nanometer scale).</p> <p style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Can%20I%20Trust%20My%20Quantitative%20EDS%20Data%201.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=iHeVhLBcmf2p1U5phWwmVO7q5BE%3D" /></p> <p>EDS, in general, is considered a semi quantitative elemental analysis technique. We are often asked how reliable are the quantitative results using SEM-EDS. This is a pretty broad question as it is dependent on a variety of factors including the sample matrix and morphology in addition to instrument considerations.</p> <p>So… what can be detected and how much? Modern systems are capable of detecting elements from Be to U. Detection limits are typically considered to be ≥1% for low atomic number elements (F to Be) and ≥0.1% (1000 ppm) for higher atomic number elements.</p> <p>One of the most common techniques used for quantitative EDS analyses is a method often described as Standardless quantitative EDS. With this method, the user does not use physical standards but instead uses a ratio of peak intensities to determine the relative abundance of the elements detected. The peak intensities are corrected for background and matrix effects and the results are then normalized to 100% based on the elements detected. This normalization can hide errors in the analysis results. With that said, if all criteria are met, one can expect around ±2% to ±5% relative for major components. However, this error can increase significantly for particles or rough surfaces.</p> <p>So, what are the criteria to consider when performing EDS quantitative analysis? Several assumptions are made with this technique regardless of whether the quantitative method is ‘Standardless’ or with physical standards. First, the sample is polished and flat. It is also homogeneous and infinitely thick relative to the beam interaction volume. If the sample is not homogeneous with respect to the beam interaction volume, the results may vary based on the contribution of neighboring components (Figure 1).</p> <p class="caption" style="text-align:center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Can%20I%20Trust%20My%20Quantitative%20EDS%20Data%202.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=BtDfGCccxIm7elmvNbElmv209jg%3D" /><br /> <strong>Figure 1</strong>: A: Homogeneous sample within the beam scattering volume. B: Heterogeneous sample, a particle within the scattering volume will contribute to EDS quantitative results</p> <p>On the other hand, it may be particles or inclusions that you are trying to identify and quantify. By placing the beam on the particle, you may get a contribution from the surrounding matrix if the scattering volume is larger than the particle itself. For non-uniform materials it is good practice to collect spectra from several different areas and average the results.</p> <p class="caption" style="text-align:center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Can%20I%20Trust%20My%20Quantitative%20EDS%20Data%203.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=b3qC0e1VkfJ62zHvLYKBlM60vDQ%3D" /><br /> <strong>Figure 2</strong>: A: X-rays are blocked from reaching the detector by sample topography. B: Rotating the stage presents the region of interest in sight of the EDS detector allowing the X-rays to be detected.</p> <p>Only those X-rays that are within line of sight to the EDS detector are collected. If the sample has significant topography, the X-rays can be blocked entirely and not reach the detector. Or, in some instances, low energy X-rays may be absorbed by the sample matrix more than higher energy X-rays contributing to error in the quantitative results.</p> <p>When dealing with a topographic sample, it is important to understand the sample position with respect to the EDS detector position. It is often possible to position the region of interest so that it has direct line of sight to the detector (Figure 2).</p> <p class="caption" style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Can%20I%20Trust%20My%20Quantitative%20EDS%20Data%204.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=NZHYugmVDjNyUDZIVQdScSM6KuQ%3D" /><br /> <strong>Figure 3</strong>: Example of C X-ray Intensity Map of Ink on Paper taken from EDS detector position 2. The ink is raised on surface of paper and the result is a shadow where C X-rays are blocked by the topography of the sample from reaching the detector.</p> <p>Finally, the accelerating voltage must be high enough for efficient excitation of the X-ray lines for the elements present in the sample and there should be sufficient probe current to generate a statistically significant X-ray count rate. What is typical is to choose an accelerating voltage that is 1.5 to 2 times higher in energy than the energy of the X-Ray lines that is of interest. For an unknown sample, 15kV to 20kV is recommended. Deviation from any of these conditions will contribute to errors in the quantitative analysis results.</p> <p class="caption" style="text-align:center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Can%20I%20Trust%20My%20Quantitative%20EDS%20Data%205.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=LRgblLX28XR7oK0SiJ9FWwpRTiw%3D" /><br /> <strong>Figure 4</strong>: Example: EDS Standardless Quantitative Results – Gold Alloy</p> <p style="margin-left: 40px;">Acquisition Condition<br /> Volt : 20.00 kV<br /> Live time : 203.01 sec.<br /> Real Time : 244.76 sec.<br /> DeadTime : 17.00 %<br /> Count Rate : 11546.00 CPS</p> Choose the Right SEM − Analysis Editionhttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/choose-the-right-sem-analysis-editionIT500Wed, 23 Jun 2021 13:12:28 GMTThe holy grail of nanoscale analysis with EDS is to quickly analyze any features which can be imaged in the SEM. However, for nanoscale features this is complicated by that fact that X-ray spatial resolution is typically larger than SEM imaging resolution. Figure 1 shows EDS maps from an integrated circuit cross section at 15kV and 6kV using a W SEM and an FE SEM, as well as the approximate X-ray signal depths at those voltages.<script> /* * rwdImageMaps jQuery plugin v1.6 * * Allows image maps to be used in a responsive design by recalculating the area coordinates to match the actual image size on load and window.resize * * Copyright (c) 2016 Matt Stow * https://github.com/stowball/jQuery-rwdImageMaps * http://mattstow.com * Licensed under the MIT license */ ; (function(a){ a.fn.rwdImageMaps=function(){ var c=this; var b=function(){ c.each(function(){ if(typeof(a(this).attr("usemap"))=="undefined"){ return} var e=this,d=a(e); a("<img />").on('load',function(){ var g="width",m="height",n=d.attr(g),j=d.attr(m); if(!n||!j){ var o=new Image(); o.src=d.attr("src"); if(!n){ n=o.width} if(!j){ j=o.height} } var f=d.width()/100,k=d.height()/100,i=d.attr("usemap").replace("#",""),l="coords"; a('map[name="'+i+'"]').find("area").each(function(){ var r=a(this); if(!r.data(l)){ r.data(l,r.attr(l))} var q=r.data(l).split(","),p=new Array(q.length); for(var h=0;h<p.length;++h){ if(h%2===0){ p[h]=parseInt(((q[h]/n)*100)*f)} else{ p[h]=parseInt(((q[h]/j)*100)*k)} } r.attr(l,p.toString())} )} ).attr("src",d.attr("src"))} )}; a(window).resize(b).trigger("resize"); return this} } )(jQuery); </script> <p>The holy grail of nanoscale analysis with EDS is to quickly analyze any features which can be imaged in the SEM. However, for nanoscale features this is complicated by that fact that X-ray spatial resolution is typically larger than SEM imaging resolution. Figure 1 shows EDS maps from an integrated circuit cross section at 15kV and 6kV using a W SEM and an FE SEM, as well as the approximate X-ray signal depths at those voltages.</p> <p style="text-align: center;"><strong><img alt="" class="img-responsive" data-gjs-type="image" draggable="true" loading="lazy" src="https://jeolusa.s3.amazonaws.com/resources_eo/JEOL%20Analysis%20SEM%20Comparisons%20FE.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=duF%2FCUCiG3RtDqxt%2BSWglqbOvhA%3D" usemap="#AnalysisMap" /><br /> Figure 1</strong>: EDS maps (same count rate/total time) from IC cross section at 15kV and 6kV using a W SEM and an FE SEM.</p> <p><map name="AnalysisMap"><area coords="337,4,770,148" href="https://fast.wistia.com/embed/channel/121ptvxx1o" shape="rect" /> <area coords="791,4,1230,151" href="https://fast.wistia.com/embed/channel/xe5ehq9rf7" shape="rect" /></map><script> $('img[usemap]').rwdImageMaps(); </script></p> <p>The W SEM is suitable for analysis of larger structures (hundreds of nm). Lowering kV allows for a smaller X-ray signal depth within the sample and thus higher X-ray spatial resolution (see the O and Al maps). If ultra-high X-ray spatial resolution is needed to resolve ~50nm layers (see the Ti maps), then an FE SEM is the best option, since FE emitters maintain a very small spot size even at low kV. Table 1 shows a comparison of some relevant parameters between thermionic tungsten emitters and Schottky field emission emitters.</p> <table class="table"> <tbody> <tr> <th>Parameters</th> <th>Thermionic Tungsten</th> <th>Schottky Field Emission</th> </tr> <tr> <td>Brightness (A cm<sup>-2</sup>sr<sup>-1</sup></td> <td>10<sup>5</sup></td> <td>10<sup>7</sup>-10<sup>8</sup></td> </tr> <tr> <td>Energy spread (eV)</td> <td>1-3</td> <td>0.5-0.6</td> </tr> <tr> <td>Life time</td> <td>~100 h</td> <td>~3 years or longer</td> </tr> </tbody> </table> <p style="text-align: center;"><strong>Table 1</strong>: A comparison of parameters between thermionic tungsten and Schottky field emission emitters.</p> Cryo Block for SEMhttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/cryo-block-for-semIT200Fri, 15 Sep 2023 11:00:00 GMTCryo-SEM imaging is a powerful tool in studying the structures of electron beam and vacuum sensitive materials. These materials include: fragile biological structures such as fungi, plants, cells, etc. as well as soft or volatile samples and even liquids. Cryo-SEM offers some clear advantages by rapidly freezing a sample prior to imaging, thus maintaining the sample as close as possible to its natural state. Long dehydration and chemical fixation steps can be avoided. Inhibiting dehydration helps maintain delicate structures without shrinkage. Moreover, volatile or even liquid samples are stabilized under the electron beam. Cryo fracturing techniques allow for study of the internal microstructure of these types of vulnerable materials as well.<h3>SMART – POWERFUL – FLEXIBLE</h3> <p>Cryo-SEM imaging is a powerful tool in studying the structures of electron beam and vacuum sensitive materials. These materials include: fragile biological structures such as fungi, plants, cells, etc. as well as soft or volatile samples and even liquids. Cryo-SEM offers some clear advantages by rapidly freezing a sample prior to imaging, thus maintaining the sample as close as possible to its natural state. Long dehydration and chemical fixation steps can be avoided. Inhibiting dehydration helps maintain delicate structures without shrinkage. Moreover, volatile or even liquid samples are stabilized under the electron beam. Cryo fracturing techniques allow for study of the internal microstructure of these types of vulnerable materials as well. A few of the disadvantages are that for efficient freezing, the sample size must be small and the price may not be in everyone’s budget for a state-of-the-art cryo system with freezing station, cold stage, vacuum transfer system etc.</p> <p class="caption" style="text-align:center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Poor%20Man's%20Cryo-SEM%201.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=oEkLBSoy8YUCLOFyw7uz5vvaIgg%3D" /><br /> <strong>Figure 1</strong>: Polymer screws isolate cryo-stub from holder</p> <p>A low cost alternative to a complete cryo-system that has been demonstrated to provide good results for many applications is a simple Cryo Block. The technique is a simple and cost effective means of looking at fully hydrated materials or other electron beam and vacuum sensitive samples. It involves pre-freezing a Cryo Block in liquid nitrogen and then contact freezing the sample prior to placing it in the SEM. The advantage of this technique is that it is simple, cost effective and the sample will in situ freeze dry in the SEM. The disadvantage is that there is no temperature control and the sample will in situ freeze dry inside the SEM.</p> <p>The supplies you’ll need are a thermos container or something suitable to put a small amount of liquid nitrogen in, a Cryo Block and cryo-glue or clamps to fix your sample to the stub.</p> <p>The sample preparation procedure is as follows:</p> <ol> <li>Immerse the Cryo-Stub in liquid nitrogen and let it equilibrate</li> <li>Once fully cooled, remove the Cryo-Stub and quickly contact freeze your sample and place inside the SEM</li> <li>Image as normal. It is helpful to insulate your cooled brass block from the basic holder –simple teflon screws or spacers would provide such insulation.</li> </ol> <p class="caption" style="text-align:center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Poor%20Man's%20Cryo-SEM%202.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=ywxfnmpfd2fS5GNe71Z8KwKgRJo%3D" /><br /> <strong>Figure 2</strong>: Orchid- Stigma anther</p> <p class="caption" style="text-align:center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/Poor%20Man's%20Cryo-SEM%203.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=VOzIDRf435NWKhxQMmSOvdZez7w%3D" /><br /> <strong>Figure 3</strong>: Sour cream</p> CryoNotehttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/cryonoteCRYO ARM™ 300Sun, 13 Feb 2022 17:08:15 GMT“Visualize the truth” is a hope of researchers who use various measuring equipment. Researchers who use electron microscopes as well have a desire to observe the real structure. But actually, in experiments using electron microscopes, many problems arise: They include damage regions of the specimen when it is cut for the size suited to observation, artifacts due to the staining that is applied to enhance image contrast, deformation caused by substitution of water to resin for withstanding vacuum exposure, and thermal damage to the specimen with electron-beam irradiation. As a result, the visualization of the real structure in the microscope image becomes increasingly difficult. One recommended solution is to cool the specimen, that is, “Cryo” techniques. This “Cryo Note” introduces some of the diversified cryo-techniques. We sincerely hope your challenge to observe the “real structure” will be solved by “Cryo” methods.<p>“Visualize the truth” is a hope of researchers who use various measuring equipment. Researchers who use electron microscopes as well have a desire to observe the real structure.</p> <p>But actually, in experiments using electron microscopes, many problems arise: They include damage regions of the specimen when it is cut for the size suited to observation, artifacts due to the staining that is applied to enhance image contrast, deformation caused by substitution of water to resin for withstanding vacuum exposure, and thermal damage to the specimen with electron-beam irradiation. As a result, the visualization of the real structure in the microscope image becomes increasingly difficult.</p> <p>One recommended solution is to cool the specimen, that is, “Cryo” techniques. This “Cryo Note” introduces some of the diversified cryo-techniques. We sincerely hope your challenge to observe the “real structure” will be solved by “Cryo” methods.</p> <p>This CryoNote includes:</p> <ul> <li>Cryo History</li> <li>A wide range of Cryo-techniques</li> <li>Freezing</li> <li>Sectioning / Fracturing</li> <li>Etching (Ice sublimation)</li> <li>Cryo-TEM</li> <li>Freeze Substitution</li> <li>Freeze Replication</li> <li>Cryo-SEM</li> <li>Low-Vacuum SEM and Cooling with Peltier element</li> <li>Cryo-FIB</li> <li>Cooling CP (Cryo-CP)</li> </ul> Designing Better Batteries Through Innovative Microscopy Characterizationhttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/designing-better-batteries-through-innovative-microscopy-characterizationIT800Thu, 10 Dec 2020 16:05:01 GMTScanning Electron Microscopes (SEM) support the development of new LIB technologies with morphological observation at the micrometer to nanometer scale, as well as the chemical analysis needed to create high-performance coatings and powders. Ultra-low voltage imaging combined with signal filtering in the SEM allows direct imaging and analysis of battery constituents (anode and cathode) with nanometer resolution. Additionally, one of the important aspects of the analysis is the ability to probe chemistry of the constituents at nm scale (Fig. 1). JEOL FESEM offers the ability to perform microanalysis with energy dispersive spectroscopy (EDS) at extremely low voltages to pinpoint localized makeup of the specimens and, in particular, low atomic number materials such as carbon and fluorine. Moreover, the unique JEOL Soft X-ray spectrometer (SXES) allows researchers to analyze Li.<p>Lithium ion batteries were commercially introduced in 1991, presenting new analytical challenges in the quest to improve on the quality, safety, and lifespan of this fastest growing battery chemistry. The basic structure of Lithium ion batteries (LIB) contains as many as 10 different thin films that are synthesized to form at least that many solid−solid interfaces. These interfaces consist of thin layers of cathode material, insulating barriers, anode materials, metal current collectors, and the electrolyte. These various components are in the form of powders, sheets, and fluids and require assessment before and after assembly and after repeated charge/discharge operations.</p> <p><strong><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/663/Designing%20Better%20Batteries%20fig1.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=UGZt9mnJTziwKTROSHqosJsMh2k%3D" /><br /> Fig. 1.</strong> EDS map of LiB cathode at 1.2kV, 6nA, 10kX. The map shows distribution of C, F, Co and O. Taken with JEOL FESEM.</p> <p>Scanning Electron Microscopes (SEM) support the development of new LIB technologies with morphological observation at the micrometer to nanometer scale, as well as the chemical analysis needed to create high-performance coatings and powders. Ultra-low voltage imaging combined with signal filtering in the SEM allows direct imaging and analysis of battery constituents (anode and cathode) with nanometer resolution. Additionally, one of the important aspects of the analysis is the ability to probe chemistry of the constituents at nm scale (Fig. 1). JEOL FESEM offers the ability to perform microanalysis with energy dispersive spectroscopy (EDS) at extremely low voltages to pinpoint localized makeup of the specimens and, in particular, low atomic number materials such as carbon and fluorine. Moreover, the unique <a href="https://www.jeolusa.com/PRODUCTS/Elemental-Analysis/Soft-X-ray-Emission-Spectrometer">JEOL Soft X-ray spectrometer (SXES)</a> allows researchers to analyze Li.</p> <p>“A significant thrust of the current research is focused on correlating electrochemical behavior to what is physically happening within the cell,” Dr. Ahmed Al-Obeidi (Ionic Materials, Woburn, Massachusetts) says. “In order to do that, one often needs to study the 3D microstructure of the battery components as well as the interfaces formed between those layers. Broad beam ion milling is a robust way to obtain clean cross sections that provides microstructural information which, when combined with EDS, enables high spatial resolution with phase and chemical mapping. LIB composed of ceramics, metallic foils and polymers present a complex system that is difficult to get an artifact-free cross section of using more traditional mechanical cross-sectioning techniques.” Ion milling is one of the only reliable techniques to get a clear sense of different layers as well as interfaces between layers (Fig. 2).</p> <p><strong><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/663/Designing%20Better%20Batteries%20fig2.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=%2FZlKTTsxfchVNGEY4HHfT1DE%2Bk4%3D" /><br /> Fig. 2.</strong> Backscatter image of LIB cross-section prepared with JEOL CP polisher.</p> <p>Moreover, for the evaluation of lithium ion battery materials that potentially react and degrade upon exposure to air, it is indispensable to have techniques to prevent the exposure of the specimen to the atmosphere. For that purpose, JEOL has established a designated workflow that includes a common air-isolated transfer vessel that is used to transfer a specimen that has been prepared in an inert gas environment (such as in a glove box) to the designated specimen preparation equipment (broad ion beam polishing equipment, <a href="https://www.jeolusa.com/PRODUCTS/Sample-Preparation-Tools/Cross-Section-Polisher">Cryo Cross-section Polisher</a>), and subsequently into the SEM through a specimen exchange chamber without exposing the specimen to the atmosphere, so that it can be observed using the FE-SEM (Fig. 3). In the example here, specimens of a lithium-ion battery positive electrode material containing LiCoO2 are first observed without being exposed to the atmosphere, and then the same location is observed after exposing the specimen to air. There are no deposits observed on the unexposed specimens, but when the same locations are observed after exposure to air, the deposits are observed. This demonstrates the effect of the transfer vessel for preventing specimen exposure to the air.</p> <p><strong><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/663/Designing%20Better%20Batteries%20fig3.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=vevwO5JmHB668Y0xJWSF%2F6KNMJs%3D" style="width: 1451px; height: 417px;" /><br /> Fig. 3:</strong> LiCoO<sub>2</sub> particles in positive electrode before and after air exposure. Clearly, air exposure introduces various artifacts affiliated with specimen reactivity with atmospheric oxygen.</p> <p>The combination of the air-isolated specimen preparation and transfer workflow and exceptional data fidelity make <a href="https://www.jeolusa.com/PRODUCTS/Sample-Preparation-Tools/Cross-Section-Polisher">JEOL FE SEMs</a> uniquely suited to meet requirements of the LIB research needs. ‘We sent our samples to get imaged over several weeks, and they were unbelievable – really beautiful images – JEOL has a very skilled team and powerful imaging capability. All of the SEMs that we had access to (until now) didn’t have an inert transfer method, which is important for electrochemical or chemically active materials, and JEOL instrumentation offers are the necessary solutions’, says Dr. Ahmed Al-Obeidi. Ionic Materials are awaiting delivery this month of the IT800 FE SEM and the Cryo Cross-section Polisher.</p> EBSD Analysis of Materials Utilizing High Temperature Protochips Aduro System in FE-SEMhttps://www.jeolusa.com/RESOURCES/Electron-Optics/Documents-Downloads/ebsd-analysis-of-materials-utilizing-high-temperature-protochips-aduro-system-in-fe-semIT800Mon, 02 Nov 2020 12:51:01 GMTIn recent years with the advances in both EBSD and FE-SEM technology there have been renewed efforts at analyzing nanostructured materials at high temperatures using dedicated specimen holders and sub-stages. Although the techniques for EBSD analysis of bulk materials using heating stages have been well established [1], the requirements for nanostructured materials preparation and analysis obviously differs from bulk materials and can benefit from a miniaturized heater with smaller sample/higher temperature capacity capability [2].<p>Natasha Erdman<sup>1</sup>, Masateru Shibata<sup>1</sup>, Dan Gardiner<sup>2</sup> and Benjamin Jacobs<sup>2</sup></p> <p><sup>1</sup> JEOL USA Inc., 11 Dearborn Rd, Peabody MA USA<br /> <sup>2</sup> Protochips Inc., 616 Hutton St. Suite 103, Raleigh NC USA</p> <p>In recent years with the advances in both EBSD and FE-SEM technology there have been renewed efforts at analyzing nanostructured materials at high temperatures using dedicated specimen holders and sub-stages. Although the techniques for EBSD analysis of bulk materials using heating stages have been well established [1], the requirements for nanostructured materials preparation and analysis obviously differs from bulk materials and can benefit from a miniaturized heater with smaller sample/higher temperature capacity capability [2].</p> <p>We have performed initial testing of a Protochips Aduro heating and electrical biasing system using a JEOL JSM-7100FT/LV FE-SEM microscope. The holder was redesigned from the original holder configuration to allow smooth transition from flat specimen experiments to 70 deg tilt required for EBSD acquisition, with no geometrical restrictions in terms of standard EBSD working distance selection or EBSD camera insertion. The holder can be inserted seamlessly through the load-lock loading mechanism, while the existing microscope stage has an adapter that connects to electrical feedthroughs that can apply a bias for heating or electrical experiments. The small heating element on the Aduro system enables fast thermal ramp rates and high thermal stability, so the specimen size is limited to approximately 50 μm and smaller, sufficient for powders and other nano-material host specimens.</p> <p>Our initial set of experiments was performed using an electrical contact, where a thin film of Au (400Å) was deposited on to of existing Ti layer (100Å). The initial Au film structure showed nano-grained material with grain size on the order of 20-100 nm (Fig. 1a). The specimen was tilted to 70deg; a small electrical current was passed through the specimen (14.5 mA) until the sufficient amount of current induced a break in the film and a significant change in Au grain structure (Fig. 1b). Fig. 2 shows the EBSD map of the break area taken at 20kV. This set of data demonstrated the potential of this holder to induce structure transformation which can be characterized via EBSD analysis.</p> <p>In this paper we will present additional examples of materials analyzed via FE-SEM and EBSD, for example Cu/Ag alloy powder, which has demonstrated dramatic transformation under increased temperature conditions (Fig. 3). Our data shows that the Protochips Aduro heating and electrical biasing system with its fine control of the temperature, the ability to reach temperatures as high as 1200 ºC and electrical biasing capability, has proven to be a viable alternative to traditional bulk holders for the analysis of nanostructured materials using EBSD.</p> <p>[1] GGE Seward, S Celotto, DJ Prior, J Wheeler, RC Pond, In situ SEM-EBSD observations of the hcp to bcc phase transformation in commercially pure titanium, Acta Materialia, 52, 821-832 (2004)<br /> [2] LF Allard, M Flytzani-Stephanopoulos, SH Overbury, Behavior of Au Species in Au/Fe2O3 Catalysts Characterized by Novel In Situ Heating Techniques and Aberration-Corrected STEM Imaging, Microscopy and Microanalysis, 16, 375-385 (2010)</p> <p class="caption" style="text-align:center;"><strong><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/EBSD%20Analysis%20of%20Materials%201.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=6PD2bNOwkXMozE5HvEA6308d62Q%3D" /><br /> Figure 1</strong>. Au (400A) film on Ti – electrical contact. (a, left) before and (b, right) after electrically induced break (image rotated 90 deg from the original orientation).</p> <p class="caption" style="text-align:center;"><strong><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/EBSD%20Analysis%20of%20Materials%202-3-4.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=gwDLH4F8exPWIdEeAWx%2B1lbSbBQ%3D" /><br /> Figure 2</strong>. EBSD data collected after electrically induced break. Top - image quality map, bottom – IPF (ND) map. 15kV, 6nA.</p> <p class="caption" style="text-align:center;"><strong><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_eo/EBSD%20Analysis%20of%20Materials%205.png?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=jdTHB8ZuTawiBKBDHhwG9VoReZA%3D" /><br /> Figure 3</strong>. Transformation of Cu/Ag powder under temperature (increasing from left to right 500->650->800->1200C). Note grain coalescence and growth as a result of elevated temperature and eventual result of a ‘molten’ ball of the alloy. Upon quenching, the ball develops faceting.</p>