JEOL Resourceshttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-DownloadsAir-Isolated Sampling of Solid-State Battery for TEMhttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/air-isolated-sampling-of-solid-state-battery-for-tem1ApplicationsThu, 23 Sep 2021 12:02:09 GMTA solid-state battery is made of cathode, anode and electrolyte. This type of battery doesn’t use liquid state electrolyte, so it tends to avoid the issues associated with leakage of electrolyte and ignition/explosion. Recently, silicon has been used as an anode material to improve the battery charge capacity (can store ten times more charge as compared to graphite anodes), but some challenges remain in terms of volume expansion during cycling, low electrical conductivity, and instability of the SEI (solid electrolyte interphase) layer caused by repeated volume changes of the Si material.<p>A solid-state battery is made of cathode, anode and electrolyte (Fig. 1). This type of battery doesn’t use liquid state electrolyte, so it tends to avoid the issues associated with leakage of electrolyte and ignition/explosion. Recently, silicon has been used as an anode material to improve the battery charge capacity (can store ten times more charge as compared to graphite anodes), but some challenges remain in terms of volume expansion during cycling, low electrical conductivity, and instability of the SEI (solid electrolyte interphase) layer caused by repeated volume changes of the Si material.</p> <p>For the purpose of observing structure and shape of anode silicon grains (charged 90 %), a TEM sample was prepared under air isolated condition.</p> <p style="text-align: center;"><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air-Isolated%20Sampling%20of%20Solid-State%20Battery%20f1.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=IgiweGxq3nmzL8xZbprIaEtDD7Q%3D" style="width: 713px; height: 384px;" /><br /> Fig. 1. The schematic of a structure of solid-state battery and charge/discharge</p> <h3>TEM Sampling Process under Air-Isolated Condition</h3> <p>A lithium battery sample was made under air-isolated conditions from start of preparation to observation to avoid reaction with air and potential oxidation (Fig. 2). For the sample transfer between instruments, a transfer vessel and slide cover holder were used. For the TEM sample preparation by FIB, an in-chamber manipulator (OmniProbe350, Oxford Instruments) was used. A cross section was first prepared by Ar-ion beam Cross-section Polisher (CP) to expose a large area showing the inner grain part of the battery, and subsequently decide the FIB processing area. JEOL air-isolated preparation methodology allows movement between all steps - CP process, SEM observation/analysis and TEM sampling - by using just one sample holder.</p> <p style="text-align: center;"><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air-Isolated%20Sampling%20of%20Solid-State%20Battery%20f2.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=463RIpHM64TJhkRUaai5MRiXzMQ%3D" style="width: 1437px; height: 756px;" /><br /> Fig. 2. Process of FIB TEM sample preparation under air-isolated condition</p> <h3>TEM sample preparation from CP-processed surface</h3> <p>A TEM sample of silicon anode material of charged all solid-state battery was made under air-isolated process which is shown in Fig. 2. Fig. 3 shows backscatter electron compositional (BEC) image and EDS map. This surface was prepared by CP. FIB process used this CP surface for choosing the correct position on the anode grain to subsequently prepare a thin TEM lamella (Fig. 4).</p> <p style="text-align: center;"><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air-Isolated%20Sampling%20of%20Solid-State%20Battery%20f3.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=SChYDHAxOpSj3OX1xiFhS%2FOsDbk%3D" style="width: 1139px; height: 444px;" /><br /> Fig. 3 SEM BEC image (left) and EDS map (right) of CP processed surface. The silicon grain position was found from SEM BEC image and EDS map. TEM lamella position is identified by the red line.</p> <p style="text-align: center;"><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air-Isolated%20Sampling%20of%20Solid-State%20Battery%20f4.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=D%2B%2FRGH4NFe1fBUF5aXwaW0Al%2FHo%3D" style="width: 1144px; height: 383px;" /><br /> Fig. 4 Images during FIB process of making TEM sample. Sample block (left) and TEM lamella (right). The sample block was made at the silicon grain position (left), and it was fixed to the FIB grid by using OmniProbe350, Oxford Instruments. After that, it was made into a lamella sample for TEM observation (right).</p> <h3>TEM observation and confirmation of air-isolated condition</h3> <p>Fig. 5 shows BF-STEM image of TEM sample. The red line encompasses the targeted silicon grain. After TEM observation, the sample was exposed to air, causing a change due to oxidation (Fig. 6). This result indicates that the entire sampling processes was indeed performed under air isolated condition.</p> <p style="text-align: center;"><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air-Isolated%20Sampling%20of%20Solid-State%20Battery%20f5.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=ZKA9Fu9WsyMwI59pz4Gl0%2BpdvWQ%3D" style="width: 522px; height: 488px;" /><br /> Fig. 5 BF-STEM image. There were three layers in silicon grain inner part from the center to outside.<br /> It is speculated that the center part was a silicon single crystal, and the lithium density increases from the center to the outside.</p> <p style="text-align: center;"><img alt="" src="https://jeolusa.s3.amazonaws.com/resources_eo/Air-Isolated%20Sampling%20of%20Solid-State%20Battery%20f6.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=IjxZvQdv2nAZIaYlln8qk%2BqBZZQ%3D" style="width: 519px; height: 488px;" /><br /> Fig. 6 BE-STEM image after exposed to air.<br /> After observation, the sample was exposed to air. Then retaken TEM image shows that it has reacted with air.</p> <p style="text-align: right;"><em>Sample provider: Prof. Atsunori Matsuda Toyohashi Univ. of Technology</em></p> Argon Beam Cross Sectioninghttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/argon-beam-cross-sectioningOperation of CPTue, 20 Oct 2020 08:36:03 GMTThe new specimen preparation apparatus, the Cross Section Polisher (CP), utilizes a broad argon ion beam that eliminates problems associated with the conventional methods of specimen cross sectioning for SEM. The CP consists of a specimen chamber with a TMP vacuum system, an optical microscope for specimen positioning, and controllers for the vacuum system and a stationary ion beam.<p>The new specimen preparation apparatus, the Cross Section Polisher (CP), utilizes a broad argon ion beam that eliminates problems associated with the conventional methods of specimen cross sectioning for SEM. The CP consists of a specimen chamber with a TMP vacuum system, an optical microscope for specimen positioning, and controllers for the vacuum system and a stationary ion beam.</p> Argon ion slicing (ArIS): a new tool to prepare super large TEM thin films from Earth and planetary materialshttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/argon-ion-slicing-aris-a-new-tool-to-prepare-super-large-tem-thin-films-from-earth-and-planetary-materialsApplicationsTue, 20 Oct 2020 09:00:05 GMTTEM foil preparation techniques commonly used in geology, material science and cosmochemistry are argon ion milling, ultramicrotomy and the Focused Ion Beam (FIB) technique. In this study we report on Argon Ion Slicing (ArIS), a new gentle preparation method which enables for the first time to prepare super large continuous and relatively smooth electron-transparent thin films (up to 50,000 µm2) suitable for TEM use. So far Argon Ion Slicing was mainly applied on mono- or bi-mineralic samples in material science. We applied and improved this promising new technique on several geo-materials including two meteorite samples to prove the viability of ArIS on complex (polycrystalline, polyphase, porous) natural samples. The successfully obtained continuous electron-transparent thin films comprise an area of 44,000 µm2 for Murchison (CM 2) and 30,000 µm2 for the Allende (CV 3) meteorite samples, respectively. ArIS is a low-energy broad-ion-beam shadowing technique and benefits from an additional protection device (a copper belt). The sample portion directly beneath the belt is protected from the ion beam. The beam "slices off" the protruding sample parts on both sides of the belt and creates a large elongated wedge. Since the developing thin film is located almost parallel to the beam propagation direction, it is almost unaffected from any irradiation damage and a phase dependent preferred thinning is not observed. Rough sample edges were smoothened with a Cross section polisher prior to ArIS treatment, which turned out to be a crucial step to produce super large electron-transparent thin films.<p>TEM foil preparation techniques commonly used in geology, material science and cosmochemistry are argon ion milling, ultramicrotomy and the Focused Ion Beam (FIB) technique. In this study we report on Argon Ion Slicing (ArIS), a new gentle preparation method which enables for the first time to prepare super large continuous and relatively smooth electron-transparent thin films (up to 50,000 µm<sup>2</sup>) suitable for TEM use. So far Argon Ion Slicing was mainly applied on mono- or bi-mineralic samples in material science. We applied and improved this promising new technique on several geo-materials including two meteorite samples to prove the viability of ArIS on complex (polycrystalline, polyphase, porous) natural samples. The successfully obtained continuous electron-transparent thin films comprise an area of 44,000 µm<sup>2</sup> for Murchison (CM 2) and 30,000 µm<sup>2</sup> for the Allende (CV 3) meteorite samples, respectively. ArIS is a low-energy broad-ion-beam shadowing technique and benefits from an additional protection device (a copper belt). The sample portion directly beneath the belt is protected from the ion beam. The beam "slices off" the protruding sample parts on both sides of the belt and creates a large elongated wedge. Since the developing thin film is located almost parallel to the beam propagation direction, it is almost unaffected from any irradiation damage and a phase dependent preferred thinning is not observed. Rough sample edges were smoothened with a Cross section polisher prior to ArIS treatment, which turned out to be a crucial step to produce super large electron-transparent thin films.</p> Artifact-free Cross-sectionshttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/artifact-free-cross-sectionsOperation of CPTue, 20 Oct 2020 08:44:36 GMTThe Cross Section Polisher (CP) is a new cross-section sample preparation device that addresses some of the issues involved with preparing very small and relatively soft specimens for SEM analysis. The CP can easily prepare a cross section that is hundreds of micrometers in width and can preserve nanometer-level fine structures.<p>The Cross Section Polisher (CP) is a new cross-section sample preparation device that addresses some of the issues involved with preparing very small and relatively soft specimens for SEM analysis. The CP can easily prepare a cross section that is hundreds of micrometers in width and can preserve nanometer-level fine structures.</p> Carbon Coater (EC-32010CC)https://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/carbon-coater-ec-32010cc1Sample PreparationMon, 19 Apr 2021 11:12:39 GMTJEOL’s Carbon Coater is a sample preparation device that evaporates carbon to create a conductive thin film on the sample surface. Thin film conductive coatings are effective in eliminating charging with non-conductive materials. Carbon has an advantage over heavy metal coatings (Ex. Gold or Platinum) for X-ray applications (EDS/WDS), CL or backscatter electron imaging due to its inherent low absorption characteristics.<h2>THIN FILM CONDUCTIVE COATING FOR SEM IMAGING</h2> <p style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/prodshots/SP/Carbon%20Coater%20EC-32010CC.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=VoJcytriT9EqAEAw7zDYQ5iCG%2B0%3D" /></p> <p>JEOL’s Carbon Coater is a sample preparation device that evaporates carbon to create a conductive thin film on the sample surface.</p> <p>Thin film conductive coatings are effective in eliminating charging with non-conductive materials. Carbon has an advantage over heavy metal coatings (Ex. Gold or Platinum) for X-ray applications (EDS/WDS), CL or backscatter electron imaging due to its inherent low absorption characteristics.</p> <p>This device is simple to use with fully automated vacuum, pre-heat and evaporation sequences. Insert your samples, turn the unit on and the chamber will automatically evacuate. Press PREHEAT to degas the carbon rod, next press EVAPORATE. The unit will automatically evaporate the carbon to create the thin film. Once the carbon evaporation is completed the system automatically vents to atmosphere.</p> <p>Film thickness can be adjusted by changing the height of the sample stage.</p> <h3>Basic Specifications</h3> <table class="table"> <tbody> <tr> <th> </th> <th>Specification</th> </tr> <tr> <td>Pressure</td> <td>≤ 20 Pa</td> </tr> <tr> <td>Carbon Electrode</td> <td>1 set</td> </tr> <tr> <td>Evaporation Source</td> <td>Dedicated High Purity Carbon Rod (1mm diameter)</td> </tr> <tr> <td>Sample Stage</td> <td>64mm (diameter)</td> </tr> <tr> <td>Source to Stage Distance</td> <td>135mm to 165mm (adjustable)</td> </tr> <tr> <td>Vent time</td> <td>30 seconds</td> </tr> <tr> <td>Evacuation System</td> <td>Directly-coupled rotary pump, 135L/min</td> </tr> <tr> <td>Evacuation Time</td> <td>3 Pa in 10 minutes (no sample in chamber)</td> </tr> </tbody> </table> <h3>Composition</h3> <table class="table"> <tbody> <tr> <th> </th> <th>Number</th> </tr> <tr> <td>Carbon Coater</td> <td>1</td> </tr> <tr> <td>Rotary pump (135L/Min), includes power supply cable</td> <td>1</td> </tr> <tr> <td>Oil Mist Trap</td> <td>1</td> </tr> <tr> <td>Carbon Rod 90mm (length) x 1mm (diameter)</td> <td>5</td> </tr> <tr> <td>Vacuum Hose</td> <td>1</td> </tr> <tr> <td>Power Cable</td> <td>1</td> </tr> <tr> <td>Instruction Manuals for Carbon Coater and Rotary pump</td> <td>1</td> </tr> </tbody> </table> <h3>Option</h3> <p>Rotating and Tilting Sample Stage (EC-30030RTS)</p> <p>This stage is useful for samples with a significant amount of topography to aid in providing a uniform coating.</p> <table class="table"> <tbody> <tr> <td>Rotation Speed</td> <td>50 ± 10 rpm</td> </tr> <tr> <td>Tilt Angle</td> <td>Horizontal to 90° (manual)</td> </tr> <tr> <td>Sample Holder</td> <td>4 stub(12.5 mm diameter) 1 stub (32 mm diameter)</td> </tr> </tbody> </table> <h3>Basic Installation Requirements</h3> <p>Clean, dry, dust free environment.<br /> Preferred footprint: 500mm (W) x 550 mm (L)</p> <table class="table"> <tbody> <tr> <th> </th> <th>Room/Space Requirements</th> </tr> <tr> <td>Temperature</td> <td>20 ± 5°C (59~77 °F)</td> </tr> <tr> <td>Humidity</td> <td>60% or less</td> </tr> <tr> <td>Power</td> <td>Single Phase AC 100V, 50/60 Hz, 1.4kVA</td> </tr> <tr> <td>Ground</td> <td>Grounding Terminal (one, 100Ω or less)</td> </tr> <tr> <td>Main Unit</td> <td>350mm (w) x 420mm (d) x 440mm (h); ~18 kg</td> </tr> <tr> <td>RP</td> <td>170mm (w) x 487.5mm (d) x 249.5mm (h); ~27 kg</td> </tr> </tbody> </table> Clean Cross Section Preparation with the SM-09010 Cross Section Polisherhttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/clean-cross-section-preparation-with-the-sm-09010-cross-section-polisherOperation of CPTue, 20 Oct 2020 08:55:10 GMTThe cross section polisher (CP), which is supported by the patented technology developed by JEOL, makes a cross section perpendicular to the surface of a specimen. This is suitable for measurement of multi-layered structures.<p>The cross section polisher (CP), which is supported by the patented technology developed by JEOL, makes a cross section perpendicular to the surface of a specimen. This is suitable for measurement of multi-layered structures.</p> Cross Section Specimen Preparation Device Using Argon Ion Beam for SEMhttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/cross-section-specimen-preparation-device-using-argon-ion-beam-for-semOperation of CPTue, 20 Oct 2020 09:27:40 GMTScanning Electron Microscopes (SEMs) have been used for various applications, such as research and development and failure analysis. There are many cases where not only observation of a specimen surface – but also observation of a cross section – is important. Preparation of a cross section depends on the specimen structure, observation purpose, and materials. Various preparation methods are put into practice: cutting, mechanical polishing, microtome, and FIB (Focused Ion Beam) are the major methods. In this discussion, we evaluate a new cross section specimen preparation method using an argon ion beam (hereinafter called the Cross-section Polishing or CP method). We have found that this method is extremely useful for observation of layer structures, interfaces, and crystalline structures of metals, ceramics, and composites. Here, we introduce examples of applications to various types of specimens.<p>Scanning Electron Microscopes (SEMs) have been used for various applications, such as research and development and failure analysis. There are many cases where not only observation of a specimen surface – but also observation of a cross section – is important. Preparation of a cross section depends on the specimen structure, observation purpose, and materials. Various preparation methods are put into practice: cutting, mechanical polishing, microtome, and FIB (Focused Ion Beam) are the major methods. In this discussion, we evaluate a new cross section specimen preparation method using an argon ion beam (hereinafter called the Cross-section Polishing or CP method). We have found that this method is extremely useful for observation of layer structures, interfaces, and crystalline structures of metals, ceramics, and composites. Here, we introduce examples of applications to various types of specimens.</p> Designing Better Batteries Through Innovative Microscopy Characterizationhttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/designing-better-batteries-through-innovative-microscopy-characterization1ApplicationsFri, 11 Dec 2020 11:06:31 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="" src="https://jeolusa.s3.amazonaws.com/resources_eo/663/Designing%20Better%20Batteries%20fig1.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=UGZt9mnJTziwKTROSHqosJsMh2k%3D" style="width: 1322px; height: 748px;" /><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="" src="https://jeolusa.s3.amazonaws.com/resources_eo/663/Designing%20Better%20Batteries%20fig2.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=%2FZlKTTsxfchVNGEY4HHfT1DE%2Bk4%3D" style="width: 1368px; height: 539px;" /><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> Direct Scanning Electron Microscopy Imaging of Ferroelectric Domains After Ion Millinghttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/direct-scanning-electron-microscopy-imaging-of-ferroelectric-domains-after-ion-millingApplicationsTue, 20 Oct 2020 09:16:50 GMTA method for directly observing the ferroelectric domain structure by scanning electron microscopy after argon ion milling has been established. Its advantages are exemplified by exposing the domain structure in three widely used ferroelectric ceramics, BaTiO3, (Na,K)NbO3, and Pb(Ti,Zr)O3. Stable high-resolution images revealing domains with widths <30 nm have been obtained. The domain contrast is caused by electron channeling and is strongly dependent on the sample tilt angle. Owing to a strain- and defect-free surface generated by gentle ion milling, pronounced orientation contrast is observed.<p>A method for directly observing the ferroelectric domain structure by scanning electron microscopy after argon ion milling has been established. Its advantages are exemplified by exposing the domain structure in three widely used ferroelectric ceramics, BaTiO<sub>3</sub>, (Na,K)NbO<sub>3</sub>, and Pb(Ti,Zr)O<sub>3</sub>. Stable high-resolution images revealing domains with widths <30 nm have been obtained. The domain contrast is caused by electron channeling and is strongly dependent on the sample tilt angle. Owing to a strain- and defect-free surface generated by gentle ion milling, pronounced orientation contrast is observed.</p> Handle with care – preparing sensitive sampleshttps://www.jeolusa.com/RESOURCES/Sample-Preparation/Documents-Downloads/handle-with-care-preparing-sensitive-samplesApplicationsThu, 23 Sep 2021 12:45:38 GMTHere we look at three types of samples that require a more precise cross sectioning technique than traditional methods: Lithium Ion battery, pharmaceutical tablet, and Zn thin film. For each, scientists need to examine a very thin multilayered “sandwich” of different materials.<p>Scientists use the ultrahigh resolution and magnification range of electron microscopy to observe nanoscale details of both surfaces and internal structures of a wide range of materials. When preparing a cross section of a sample to reveal the internal structure, they need to consider the properties of the samples and be aware of their potential to crumble or melt or change due to exposure to air. Some samples are composites with layers of different materials, both hard and soft, and they can also range in sensitivity to temperature and exposure to air.</p> <p>Creating a pristine cross section to see internal structuring for such samples is not as simple as cutting with a sharp razor blade, polishing with sandpaper, or using a microtome. None of these options work without smearing or crumbling of coatings and complex internal layers, and also adding artifacts. For this purpose, JEOL developed an <a href="https://www.jeolusa.com/PRODUCTS/Sample-Preparation-Tools/Cross-Section-Polisher">ion beam milling system</a> that could create pristine samples of coated papers, powders, and metals, plus a cooled ion beam milling system with special handling for air-sensitive samples like lithium ion batteries.</p> <p>Here we look at three types of samples that require a more precise cross sectioning technique than traditional methods: Lithium Ion battery, pharmaceutical tablet, and Zn thin film. For each, scientists need to examine a very thin multilayered “sandwich” of different materials.</p> <h3>Temperature and Air-Sensitive Lithium Ion Batteries</h3> <p>The basic structure of Lithium Ion batteries (LIB) contains as many as 10 different thin films and 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. Researchers who are correlating electrochemical behavior to what is physically happening within the cell need to study the 3D microstructure of the battery components as well as the interfaces formed between those layers.</p> <p>For Lithium ion battery materials that potentially react and degrade upon exposure to air, it is indispensable to have <a href="https://www.jeolusa.com/PRODUCTS/Sample-Preparation-Tools/Cross-Section-Polisher/Lithium-Ion-Battery-Sample-Preparation">techniques to prevent the exposure of the specimen</a> to the atmosphere during sample preparation, and even in introduction to the electron microscope. For that purpose, JEOL has established a <a href="https://www.jeolusa.com/BLOG/designing-better-batteries-through-innovative-microscopy-characterization2">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</a> (such as in a glove box) to the designated specimen preparation equipment (broad ion beam polishing equipment, Cryo Cross-section Polisher), and subsequently into the SEM through a specimen exchange chamber without exposing the specimen to the atmosphere.</p> <p style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_sp/Handle%20with%20care%20%E2%80%93%20preparing%20sensitive%20samples%2001.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=ev54mChh6%2Fmn7ZLzZ3kK9qEuw4Q%3D" /><br /> Backscatter SEM image of Lithium Ion Battery Cross Section prepared with JEOL Cross Section Polisher</p> <h3>Complex Layers in Pharmaceutical Tablets</h3> <p style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_sp/Handle%20with%20care%20%E2%80%93%20preparing%20sensitive%20samples%2002.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=Iu17oTpgAi0YaTylaxdvW8hCDHM%3D" /><br /> Cross section processed (a) at room temperature and (b) -120°C.</p> <p>To help ensure the proper functions of pharmaceutical tablets, such as sustained or enteric release that influence the effect of the medicine on the body, it may be necessary to observe the tablet’s structure and components. Cross sections of tablets are generally very difficult to prepare due to the fragility and softness of the materials. Preparation damage might cause sample deformation such as peel-off of the coating layers after razor blade cutting or mechanical polishing. Using broad argon ion beam milling instead creates high quality cross sections. Since some tablets contain substances with low-melting point such as starch and beeswax, thermal damage in the process might cause sample deformation. In this case utilizing <a href="https://www.jeolusa.com/PRODUCTS/Sample-Preparation-Tools/Cross-Section-Polisher">liquid nitrogen (LN2) cooling during the ion milling is preferred</a>.</p> <h3>Structural Details and Crystallographic Orientation of Thin Films</h3> <p style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_sp/Handle%20with%20care%20%E2%80%93%20preparing%20sensitive%20samples%2003.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=ICoA%2BOc64hv547YiaGI7dD6W8SA%3D" /><br /> Zn coating on steel prepared at RT (left) and using cooling (right). The image shows preserved thin-film/substrate and crystallographic integrity.</p> <p>Examination of materials cross sections often provides essential information about the crystal structure, layer or film thicknesses, existence of voids or cracks and other properties that might impact materials performance and reliability. Cross-sectional observation is especially essential in thin film technology to examine layer thickness, deposition integrity (voids/adhesion), as well as film growth and crystallographic orientation. Currently various methods are used to prepare specimen cross sections for scanning electron microscope (SEM) observation. Mechanical methods of cutting and polishing are widely used, particularly for metallographic sample preparation. However, mechanical polishing presents several problems: a) in composite materials with different hardness values, the polished surface becomes uneven as the softer components are cut faster and more easily than the harder components; b) in soft materials, particles of hard abrasive can be buried in the material being polished; c) in materials with voids, the edges of the voids can stretch and deform; e) for metals, due to the strain caused by mechanical polishing on the polished surface, the information about the crystal structure by means of electron back-scatter diffraction (EBSD) becomes difficult or impossible to obtain; f) fine features like hairline cracks and small voids can get smeared shut and will not be recognized as such.</p> <h3>Conclusion</h3> <p>Only broad ion beam milling with consideration for sample properties can produce clean cross sections for electron microscopy. The pristine samples provide microstructural information, and, when analyzed with SEM-EDS, produce data with high spatial resolution with phase and chemical mapping.</p> <p>Ion milling is one of the only reliable techniques to get a clear sense of different layers as well as interfaces between layers – all without artifacts.</p> <p style="text-align: center;"><img alt="" class="img-responsive" src="https://jeolusa.s3.amazonaws.com/resources_sp/Handle%20with%20care%20%E2%80%93%20preparing%20sensitive%20samples%2004.jpg?AWSAccessKeyId=AKIAQJOI4KIAZPDULHNL&Expires=2145934800&Signature=um7u28eOW1ZPJnF88BGgtPVS6mY%3D" /><br /> Schematic of cooling broad ion beam polisher (JEOL IB-19520CCP Cross Section Polisher)</p>