Transmission electron microscopy of bulk specimens over 10 µm in thickness

Abstract

We succeeded the observation of microstructures in bulk-sized specimens of over 10µm in thickness by employing a technique that combines transmission electron microscopy (TEM) with energy-filtered imaging based on electron energy-loss spectroscopy (EELS). This method is unique in that it incorporates the inelastically scattered electrons into the imaging process. Using this technique, bright and sharp images of dislocations in crystalline silicon specimens as thick as 10µm were obtained. A calibration curve to determine foil thickness of such a thick specimen was also derived. This method simply extends the observable thickness range in TEM. If combined with tilt series of observation over a significant range of angle, it will disclose three dimensional nanostructures in a µm-order block of a specimen, promoting our understanding of the controlling mechanisms behind various bulky material properties.

Three-Dimensional Imaging of a Long-Period Stacking Ordered Phase in Mg₉₇Zn₁Gd₂ Using High-Voltage Electron Microscopy

“…It is noted that the precipitate is highly enriched in solute elements of Zn and Gd, in contrast to the α-Mg matrix. Fine bright straight lines seen around the precipitate are solute-segregated stacking faults (SFs) 8) , which appear as atomic number (Z) contrasts. Correspondingly, electron diffraction shows weak streaks in the [0001]* Mg direction.…”

“…According to the literature, the maximum observable limit for electrons accelerated at 1 MV is as thick as 15 μm for Al 6) and 8 μm for Si 7) . Recently, Sadamatsu et al succeeded in imaging dislocations in Si as thick as 10 μm using HVEM equipped with an in-column type energy lter 8) . Thus, HVEM is a promising technique to visualize interior structures of a thick specimen.…”

In Situ Observation of Liquid Solder Alloys and Solid Substrate Reactions Using High-Voltage Transmission Electron Microscopy

“…From the TEM viewing screen, a Cu 6 Sn 5 grain was selected. To enhance the image contrast in the thick (500 nm) sample, an in-column omega-type filter was used to filter the plasmon contributions to the image [21,22]. The sample was tilted to a low-index zone axis of this grain and selected area electron diffraction (SAED) patterns were obtained.…”

Imaging the Polymorphic Transformation in a Single Cu6Sn5 Grain in a Solder Joint

“…The thick lamella sample (Figure 1a) was characterised using a JEM-1300NEF (JEOL, Akishima, Japan) at an accelerating voltage of 1250 kV. This HV-TEM at the Research Laboratory for High Voltage Electron Microscopy, Kyushu University, is equipped with an in-column omega-type energy filter and this has the advantage of allowing thicker specimens to be imaged at higher contrast [19,20]. The beam induced heating on Cu 6 Sn 5 is about 0.5 times less (see Appendix A) in the case of high voltage compared to conventional low voltage TEM, allowing for proper observations on the metastable sample.…”