Sample Preparation Equipment Documents

A 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.

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.

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.

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.

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.

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.

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.

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 JEOL Soft X-ray spectrometer (SXES) allows researchers to analyze Li.

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, 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.

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.