Sample Coating for SEM October 20, 2020 JEOL Smart Coater, Sample Preparation 0 Modern day Scanning Electron Microscopes (SEMs) are capable of imaging at ultralow voltages or low vacuum modes to handle even the most non-ideal sample types without the need for extensive sample preparation. Low voltage, with its inherent low beam penetration into the sample, allows us to examine fine surface morphology. The added advantage to low voltage imaging is the ability to look at nonconductive samples and minimize charging artifacts. Low vacuum, on the other hand, allows us to look at and analyze non-conductive and outgassing samples at higher voltages required for other analytical techniques such as X-ray Analysis (EDS/WDS), Cathodoluminescence (CL) or Electron Backscatter Diffraction (EBSD). Thus, we have the tools to analyze many sample types with minimal to no sample preparation. A question often asked is with the versatility of today’s SEMs, is there any reason to add a conductive coating when preparing samples for the SEM? And if I add a conductive coating, what do I coat it with? There are a lot of options. For full details: Attached files often contain the full content of the item you are viewing. Be sure and view any attachments. TN-Sample Preparation - Coating.pdf 391.41 KB Related Articles New Cross-Section Sample Preparation Method Applied to Microstructural and Chemical Investigation of Steel Coatings using FE-SEM Steel strips coated with Al-43.5Zn-1.5Si (Galvalume) alloy exhibit superior corrosion resistance as compared to Zn galvanized steel strips. The continuous hot-dip coating process used to produce such coatings entails a metallurgical reaction between the steel strip and Al-Zn-Si liquid alloy that leads to formation of an intermetallic compound layer at the steel-coating interface. Formability of the coated strip depends strongly on the morphology, dimensions (thickness) and chemical nature of this intermetallic layer. Proper characterization of the intermetallic layer structure and chemistry and the nucleation sites on the steel surface is therefore of paramount importance for the development of formable Galvalume coated steel strips. This requires preparation of artifact free cross-sectional samples. Such samples can be obtained using JEOL Cross-section Polisher (CP). Unlike mechanical sample preparation techniques that introduce significant amount of strain and possible artifacts due to preferential etching of various constituents, the CP uses a broad Ar beam and a rocking stage that minimize possible preferential etching and produces strain free cross-sections. In this paper, SEM images as well as chemical (EDS) data characterizing the interface layer between the steel strip and the Galvalume coating prepared using Cross-sectional Polisher are presented. Handle with care – preparing sensitive samples 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. Ion beam sputter coating with CROSS SECTION POLISHER™ CROSS SECTION POLISHER™ (CP) is an SEM specimen preparation device that utilized broad Ar ion beam to produce artifact-free cross-sections. The same principle can be employed not only for ion-milling but also deposition of thin layer to the specimen surface, in particular conductive coating for followup observation of a non-conductive specimen in an SEM. Pristine Sample Preparation Using Broad Ion Beam Traditional mechanical preparation of specimen surfaces suffers from various artifacts, such as scratches and embedded polishing media, that obscure the original microstructure, crystallographic information and precise layer thickness measurements. Broad ion beam polishing using the JEOL cross-section polisher (CP) offers pristine surface preparation with minimal artifacts. CP is a tabletop instrument that is ideally suited for preparation of a variety of environmentally-sensitive and beam-sensitive materials, including metals, polymers, ceramics and composites. The instrument includes both cryo-preparation (down to LN2temperature) and air-isolated transfer and preparation environment. Argon ion slicing (ArIS): a new tool to prepare super large TEM thin films from Earth and planetary materials 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 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. Carbon Coater (EC-32010CC) JEOL’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. Showing 0 Comment Comments are closed.