Introduction

The Zeiss SEM is the SEM in the metrology bay of the cleanroom. While we have our own SEM (the Vega3 TESCAN SEM), sometimes its convenient to use the cleanroom one since you don't need to take your samples out of the cleanroom. The problem is that it is an incredibly popular piece of equipment, so understanding how to use quickly, efficiently, and safely is critical. The consensus from our group is that this training/certification is appreciably more difficult than the CHA training/certification (at least for most users). If you know how to use our SEM, most (but not all) of this should be familiar

If you are getting trained/certified, the most important advice is in bold. Rico will ask you about this stuff!

Before training, watch the YouTube video Rico sends you. It has good advice, and seeing the process before training goes a long way.

Also, Rico asks to leave the tool boxes outside of the SEM bay. So just take your sample with you. 

The certification will involve two measurements: top-down and a cross-section. 

Sample Mounting and Exchange

1. The first thing you need to do when you reach the tool is log into the software. The previous user should have logged out. Your login will be created by Rico after you get certified.
2. Next, you can vent the chamber by clicking the "Sample Exchange" button (there's also a button on the hard panel for this). Partway through the vent process, there will be a dialog box. Click "Ignore". While the chamber vents (~3 minutes), it is a good time to mount your sample on a chuck.
3. Once the chamber is vented, slowly pull the chamber door away from the column. You can tell the chamber is vented if there is separation (*not* gap) between the door and the column. At about 4in separation, check that the stage is centered. If yes, proceed opening, if not, use the joystick to move the stage to the center and then open. If there is a sample chuck (there shouldn't be), take it off by removing it from left to right. If you meet unexpected resistance, make sure the stage is rotated to the 0° position.
4. Insert the chuck with your sample on it by sliding it in from right to left (if you are looking directly at the column from the door). Make sure the flat side of the chuck is on the left side.
5. Close the door of the chamber slowly. Evacuate the chamber by clicking the dropdown dialog next to the "Sample Exchange" process and clicking "Resume". There's also a button on the hard panel for this. This does three things in a certain order. It evacuates the chamber, raises the stage to 20mm, and turns on the electron beam (Electrical High Tension = EHT). For the first few seconds of evacuation, firmly push the door closed to ensure a good seal and to prevent contamination of the chamber.

Adjusting the Stage and Acquiring the Image

1. You need to change the stage. In the "Stage Navigation" window, select the type of chuck you are using from the dropdown dialog box. The names are pretty intuitive.
2. Set the height of the stage based on the samples on it.
3. Acquire/align your sample. Do *not* say "find" the sample. Changing the detector to be "TV" use the xy-joystick to position the sample. Switch to "Aux", and adjust the position a bit more. Check the positioning by changing back to "SE2". The detector may have started on the "In-Lens", but you can switch off of it.
4. Raise your sample. DO NOT USE THE JOYSTICK. Instead, use the z-axis box in the sample navigation window. Type in a number, press enter, and hover your mouse over the "Stop" button. This is to prevent the samples from crashing into the column. The stage should stop at the z-position you specify, but you hover to stop it in case you specified a number that is too large. Be careful of other samples that are loaded (hint for the cross-section part of certification).
5. Now you need to "Acquire your sample (again?)". Use the x-y joystick (at minimal magnification and some rough coarse focus if needed) to find the sample and features you are interested in.

Finding Your Features

1. Once you are in position, magnify until you have reached a scale similar to the size of your feature (a bit larger if you need to search). You can use the "Center" macro to quickly move your samples if needed. Adjust the focus (coarse) once so you have an easier time finding your features. At this point, you may need to find features.
2. If you are looking at a side profile or cross section of your sample, you will need to tilt the stage. You should know the angle needed from the type of chuck you need, but keep in mind that the stage has a -10° to +60° range of motion. You may need to rotate the stage by 180° if this is the case.
3. If needed, scan the surface for features in a matrix pattern. Rico will ask you to do this. To more easily find the features, you'll probably need to be magnified out a bit.
4. If you find something close to your feature size, the scale bar will not be accurate unless you zoom in on the feature. Do this if you need to measure.
5. Once you have acquired your features, you can play with the focus and stigmation until the sample is in focus. If needed, switch the detector to the "In Lens". Make sure to be magnified close enough to be able to focus (using WD) on your features. 
6. Repeat as necessary.
7. You can also use Scan Rotate know to rotate the image, not the actual stage. Press down on the knob and rotate to needed image. If press down again - it remembers the original position and will return the image to that. 

Unloading Your Samples

Unloading is much the same as loading, with a few differences.

1. Check to see if there is appropriate "Clearance" between the samples and the cone. If your samples are close to the nose cone, you do not have clearance!
2. If you don't have clearance, lower your sample and the chuck a few millimeters to ensure you have clearance. Don't worry if the stage is still tilted at this point.
3. If you have clearance, proceed with the "Sample Exchange" as detailed earlier in this guide. This does three things: First, it turns off the electron source. Second, it lowers the stage to 10mm and fixes the tilt/translation. Third, it finishes lowering the stage and vents the chamber. When you have hit the "Sample Exchange", move your cursor to "Stop" button just in case. 
4. Remove your samples similarly to how you loaded them. If the chuck does not come out, you likely have a problem with the rotation of the stage. Use the stage navigation panel to rotate the stage to 0°.
5. If the next user is waiting for the equipment, ask them if they want you to leave the chamber vented. If not, evacuate the chamber as detailed previously, fill out the logbook and log out of the tool.
6. Images will be saved in the "Image" folder. Transfer them into the Z-Drive and then get them onto the flash-drive from outside the cleanroom. 
7. Sign out of the SEM using the LabAccess Computer.