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Breakerspace SEM Tutorial

Overview

The Breakerspace has two scanning electron microscopes (SEM), a ThermoFisher Phenom XL and Phenom Pure.

SEMs use a focused beam of electrons to image materials at much higher magnification than can be achieved with an optical microscope, with our instruments able to resolve features as small as 100 nm in optimum conditions.

Our Phenom XL has a large 100x100 mm sample stage, a low vacuum mode for non-conducting samples, can perform energy dispersive spectroscopy (EDS), and also has a tensile stage for in-situ observation of mechanical experiments. The Phenom Pure can observe a single sample on an 18 mm or smaller stub, under either low or high vacuum, and has a cold-stage for observation of frozen samples. Both instruments have backscatter (BSD) and secondary electron (SED) detectors.

Index:

Standard operating protocol:

Instrument startup:

Operation:

Instrument shut down:

Compatible materials and sample prep:

If you have any questions about whether a material is appropriate to characterize in the Breakerspace, please ask before bringing it to the lab.

Sample prep basics:

Solid sample prep (basic)

Detailed operating instructions:

Sample loading:

Characterization:

Customize: When your sample is loading, this is a good time to visit Settings/Customize and change the Label and Location fields to a name and folder that are relevant to your project

NavCam: When you first load a sample into the SEM you see your sample(s) on the NavCam. This is an optical image of the sample stage that can be used for navigation once you are in SEM observation mode. If you will rely on the NavCam image for navigating your sample(s), it is helpful at this stage to make sure the brightness, contrast, and focus are all acceptable in key areas of your sample. If you wish, you can click the camera icon in the NavCam to save the NavCam image to a file.

LiveSEM view: Once you click “Move to SEM” add image you will be in the LiveSEM view. Here you can adjust brightness, contrast, and focus, as well as changing magnification. The recommended UI setup is to leave the scroll wheel set to change magnfication, hold down the right mouse button and move the mouse cursor horizontally to change focus, and to use auto brightness/contrast. A full set of keyboard and mouse shortcuts can be found in Settings/Phenom/Help. Detailed operating instructions and a full UI overview can be found starting on page 20 of either the XL or Pure manual.

Gallery: The gallery will show you all images in the active folder. In addition to reviewing the images, you can add dimensions and notes. If you annotate the images the annotated versions need to be saved as new files.

Acquisition: Press the camera icon on the left side of the screen to acquire an image. Images will be saved in the resolution and with the averaging specified in the Operational Settings/Acquisition menu. Pay attention to acquisition times, and take some test images first. Higher averaging settings swill increase signal to noise, and result in cleaner images, but longer acquisition times. If there are issues related to charging, such as drift, they will be more visible in longer acquisitions, so higher averaging is not always better or needed.

EDS: Energy dispersive spectroscopy (EDS), available on the Phenom XL, allows you to perform elemental analysis and save out full reports, included map images, images and data of captured spectrum, and a CSV files with raw data. Recommended settings for EDS are 15kV acceleration voltage and map beam intensity. Click the square to stop data collection before navigating to a different section.

Live EDS: Live EDS mode, (Phenom XL only) lets you perform quick elemental analysis on a spot on your sample, without generating any files or documentation. It is useful for quick spot checks. Recommended settings for EDS are 15kV acceleration voltage and map beam intensity. Click the square to stop data collection before navigating to a different section.

For a more complete description and instructions on how to use any of these features, please see the XL or Pure manuals.

Sample unloading:

Common failure modes:

Manufacturer’s manuals:

Exercises: