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I. Introduction

What is the SEM-EDS? What does the SEM-EDS do? What are additional resources (link them here)

This Quick Start Guide builds on the SEC SEM Quick Start Guide, so it is assumed that the user first goes through and understands its contents.

II. Procedure

A. Sample Preparation For EDS

The analyzed surface should be clean and dry, well-polished, and have an electrically conductive coating (usually carbon) applied with the Leica EM ACE200 vacuum coater located on the ship. Typical sample preparations for EDS are polished thin sections, or polished grain mounts. Contact the Core Description technician for help with the vacuum coater and SEM-EDS, or the Thin Section technician for questions about EDS sample preparation.

B. Esprit Compact Software Startup

  1. Start ESPRIT Compact by clicking the program icon on the desktop or in the start menu. The login screen is displayed, prompting for username and password.
  2. Enter the username and password and click the login button. IMAGE OF THE DESKTOP ICON AND THE LOGIN POPUP <----set them up as main user
  3. Use the arrow icon on the bottom left corner of the EDS configurator to open the EDS Detector Configuration dialogue and set Pulse throughput and Maximum energy to Automatic. Check that the detector temperature status indicator is green.
  4. Note the input count rate (ICR) in the EDS detector configuration box. This should be between 1.0-10 kcps (thousand counts per second) at minimum, and instructions to adjust microscope parameters to increase counts are in the following section. If the input count rate is too low, try the following steps. 
    1. Verify that the SEM is operating with a working distance of 7-10 mm (Focus area of Nanoeye software)
    2. Adjust the position of the second condenser lens (CL2 in the EDS menu of the Nanoeye software)
    3. Consider increasing the accelerating voltage of the SEM, up to a maximum of 20 kV. Note that this may increase the undesireable effects of built-up electric charge, which diminishes image and EDS quality.
    4. Ask a technician for help with aligning the strip aperture and aligning the electron gun. Instructions will go in User Guide

C. SEM Imaging Prior To EDS

To prepare for EDS, the user will first use the Nanoeye software to collect a good image of the portion of the slide where they plan to conduct their EDS work, by following the instructions in the SEM SOP and using the following recommended settings and techniques:

  1. Choose an accelerating voltage of 10-15 kV, or a maximum of 20 kV for more counts or if high Z major elements are expected.
  2. Focus the microscope using SE (secondary electron) mode, before switching to BSE (back-scatter electron) mode for most geological applications. Obtaining a good focus on a highly polished thin section can be difficult; a helpful technique may be to focus on a piece of carbon tape, before moving to a small physical feature on the thin section.
  3. The optimal working distance for EDS analyses is 7-10 mm (visible in the Focus Area panel of the Nanoeye software). This will require lowering the specimen stage (increasing the Z value to a higher positive number) in the Nanoeye software stage controls by Z = +7-10 mm and adjusting the focus accordingly, until the specimen is in focus at a working distance of 7-10 mm. Note that the focal plane should be at approximately Z - height of sample [mm] = working distance [mm].
  4. Use a small spot size of 0-10%. This can be adjusted in the beam area using the Size(%) slider, or using the CL1 slider in the EDS menu.
  5. Detector sensitivity can be adjusted between preset values in the EDS menu, between 1 (least sensitive) and 5 (most sensitive)
  6. To increase the number of electron counts, the position of the second condenser lens can be adjusted down using the CL2 slider in the EDS menu. Aim for between 1.0-10 kcps (thousand counts per second).

The user should collect a good image of the region of the sample where they are planning to perform the EDS analyses. This image will form the basis on which EDS analyses will be uploaded into the database.

Recommended data storage structure

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D. Choose A Workspace

In ESPRIT Compact, there are three methods to capture electron microscope images, each which has their own section ("workspace") in the software. These are:

  • Objects:
  • LineScan:
  • Mapping:

The user must select the appropriate workspace that corresponds to the type of analyses they would like to do first. Multiple types of analyses may be conducted during the same session, provided that data are saved as you go along.

Picture of the top ribbon showing the different workspace buttons

E. Capture An Image

  1. Select a workspace based on the type of analyses you would like to perform (Objects, LineScan, Mapping).
  2. Optionally, Use the arrow icon in the bottom left corner of the Scan configurator to open the Scan Configuration menuimage
    1. Recommended settings:
      1. Image resolution: 512 pixels for Object and Line data acquisition, 1000 pixels for Map acquisition
      2. Dwell time (us): 8 us
      3. Line average: 1
  3. Optionally, click on the Capture dropdown arrow to set capture parameters and Image number of Automatic numbering
  4. Click on the Capture button to Capture an image
  5. Above the image, select Ch1/SE or Ch2/BSE according to what type of SEM image you wish to capture.image
  6. Right mouse click the image to change image parameters such as legend and brightness/contrast
    1. Right mouse click the image, then click Properties to change image legend
    2. Right mouse click the image, then click Histogram to change image brightness/contrast.image
  7. If a good image is not showing up, you may need to go into the Nanoeye software to change the SEM parameters, under the EDS pop-up menu:
    1. Detector sensitivity
    2. CL1, CL2 image
  8. Right click on the image to Save image (recommended), Copy image or Add image to report .

F. Acquire A Spectrum

For Object Scans

For Line Scans

For Mapping

G. Quantify A Spectrum

H. Save Data

III. Uploading Data to LIMS

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IV. Preventative Maintenance

Regularly

  • Check the energy-channel calibration as detailed in section 5.2 (pg. 43) of the Esprit Compact user manual.

IV. Credits

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V. Archived Versions

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