LEO 1530 Thermally-Assisted Field Emission (TFE) Scanning Electron Microscope (SEM)

Operating Instructions

  • Logging in:
  • Check that Green “on” button on the front panel of the instrument is lit up. If not, turn on green button on the front panel, and the PC next to the benchtop.
  • Log into SUMS. using the computer to the right The SEM monitor will power up.
  • Double click on the SmartSEM Interface Icon on the desktop
  • Log in using “User Name” and Password.
Inserting a sample Manually (No macros)
  • Turn on the chamberscope by left clicking on the chamberscope icon.
  • Vent the chamber by clicking on “Vac” in the Status Bar at the bottom of the LEO UIF (User Interface) then clicking on the “Vent” which pops up.
  • Answer “yes” to the pop up window.
  • Put samples already attached to the sample holder into the chamber, making sure it is secure on the stage. May need to twist the sample holder to get it lined up.
  • Close door and hold shut.
  • Click on “Vac” in the Status bar, and click on the “Pump” which pops up.
  • The sample can be moved under the lens and positioned using the x and y axis adjustment of the joystick or the encoders. The sample is under the final lens when the Chamberscope image shows the sample in focus, or the leading edge shows the same brightness and contrast as the metal strip on the front of the lens.
  • Adjust the sample height using the joystick’s z- adjustment.

 

Turning on the Beam
  • The system reaches “Vac” ready (a green checkmark next to “Vac” in the Status Bar) at 1.5e-5 torr, shown on the “vacuum” control tab of the SEM Vacuum Status Panel [ctrl+G]) then click on “EHT” in the Status bar and select “EHT On” to turn on the beam. The beam cannot be turned on until the vacuum reaches this level. Check the voltage setting under the “Gun” tab of the SEM Vacuum Status Panel.
  • The Status bar will display a blue bar with the comment “Running up”.
  • Record the values for vacuum, EHT and current for your session on the paper log sheet.
  • Once the EHT is on, turn off the chamberscope ; check that Signal A is set to a detector. (InLens is best at <20 kV; only SE is possible at 20 kV and above.)  If “Signal A = –” then press the “Detector .  Select” icon,twice. (This icon will toggle detectors.) Or, select a detector from the “Detection” drop down menu.

 

Finding the Sample
  • In the pulldown menu, choose Stage, then Navigation; check to see that you are on the sample stage, as shown in the schematic
  • Set the Mouse to “Mag/Focus” by clicking  (The Left button [LB] will be equal to Magnification, and the Middle button [MB] will be equal to Focus)
  • To Adjust Mag, click and hold down the LB and move left to right to increase mag, and right to left to decrease mag.
  • To adjust Focus, click the MB and hold it down and move left to right to focus closer to the lens, and right to left to focus farther from the final lens.
  • Lower the mag to the minimum, 68X, at least. Pressing the MB while clicking on will  automatically set the microscope to the lowest mag.
  • Focus using the MB

 

Adjusting the Beam (Things to look for to be sure the beam is aligned)
  • Focus the image at a mag slightly higher than you want to use for your final picture.
  • While changing the focus (moving the mouse left to right and right to left while holding down the middle mouse button after left clicking on the “mag/focus button” . Does the Image:

 

“Shift or Translate” (not stationary when focus is changed in and out)

  • Focus the Image to the best possible setting.
  • Middle Click on the Stigmation/Alignment Icon 
  • This will turn on the focus wobble, and set the mouse to LB=x-aperture align, and MB=y-aperture align and the SEM Control Panel will pop up.
  • Do the Aperture Alignment by using the mouse button assignments, or by using the Navigation panel (Nav Box) on the SEM Control Panel Aperture tab. The object of alignment is to stop the “Wobble.” If the image is shifting up and down, use the y-aperture alignment assigned to the MB, or use the up and down arrows on the Nav Box. Adjust until movement in either the up or down direction is minimized or stopped. IF the image displays movement in the left, right directions then the user should make adjustments using the x-axis alignment assigned to the LB of the mouse, or use the left or right arrows on the Nav Box. Go back and forth until the shift, movement, or translation are minimized or completely stopped. Once this is accomplished turn the wobble off.

 

Check the Focus, and then the Stigmation.
“Smear and tear” (go out of focus unevenly) Stigmation Adjustment

  • If the answer is “yes” Focus in and out finding the point at which the image is between the smear and the tear. A middle point in the focus where the image isn’t stretched in any particular direction. Adjust the stigmation (stig) by left clicking on the “Stigmation/Alignment” Icon  . This will set the LB to x -axis stigmation, and the MB to y-axis stigmation.
  • Use these two buttons to make adjustments: clicking on them, holding the button down, and moving back and forth, left to right, in order to better focus the image.
  • Select Mag/Focus, adjust focus back and forth, checking the image for smearing and tearing. If it is gone then you are done; otherwise repeat the steps from the beginning until the image reaches its best focus.

 

Recording an Image
  • After the image has been adjusted to your satisfaction, left click on the Freeze/Unfreeze icon . A blue dot will appear in the lower righthand corner of the screen, indicating that the image is no longer live.
  • Right click on the screen background; a box called “Properties” pops up with an arrow to the right. Drag the mouse over the box, to the right to see the options for saving your image: TIFF, BMP, JPEG.
  • Pick your preferred format, and click on it. A large control box will pop up with three tabs. Under the first tab, your image directory is listed. Save files here, by giving the image a file name, then clicking on the “Save File” button. Under the Settings tab, you may change the “Image Number” and number of characters that may be used to assign a file name. [Also, Grey and Palette should be selected.] Under the Data tab, instrument parameters that may be included in the image file are listed. Click on the parameter, to include it with the file.
    • Alternatively, images may be saved by choosing File on the menu bar, then Save Image. The large control box will again appear on the screen, and a file name may be entered.
    • Unfreeze the image after the image has been recorded by pressing the Scroll Lock button on the keyboard.

 

To Log Off During the Day:
  • Turn off the EHT; leave the Gun ON, unless you are the last user of the day.
  • Remove sample from chamber (See “Inserting sample” above). Leave chamber under vacuum.
  • On the “File” Pull down Menu, select Log Off or click on the x in the upper right hand part of the SEM UIF
  • Answer “Yes” to the question.

 

To Log Off as the Last User of the Day:
  • Close the EM Server by clicking the red X in the right corner.
  • Turn off the PC by going to the Windows’ Start menu and clicking “Shut down”.
  • Choose “Shut Down the Computer”
  • Answer “yes” to the question

 

When the Screen Displays “It is safe to turn off your computer” press the Yellow “standby” button on the front panel of the SEM.

 

LEO Keys

The following keys are shortcut keys and have special meaning

<F2> Toggles Tool Bar on/off
<F2 + SHIFT> Hysteresis removal
<F3> Closes all windows except the Tool Bar and Status Bar
<F3 + SHIFT> Toggles PC Plane ON/OFF
<F4> Step to next Magnification Table entry, or Undo Center Feature Magnification
<F4 + SHIFT> Exit from Magnification Table mode.
<F5>, <F5 + SHIFT> User defined macros
<F6>, <F6 + SHIFT> User defined macros
<F7>, <F7 + SHIFT> User defined macros
<F8>, <F8 + SHIFT> User defined macros
<F9> Keys help (displays this information)
<F11>, <F11 + SHIFT> User defined macros
<F12>, <F12 + SHIFT> Aborts Stage Movement.
<TAB> Toggle coarse/fine
<CTRL + TAB> Performs Center Point
<CTRL + SHIFT + TAB> Performs Center Feature
<HOME> Resets Beam Shift to zero.
<SCROLL LOCK> Toggles Freeze/Unfreeze
<PAUSE> Causes currently executing macro to continue
<*> Performs Find Image function.
<CTRL + 2> Loads Second Image Window from display
<CTRL + A> Switches Annotation panel ON
<CTRL + B> Display Toolbar View dialog
<CTRL + D> Toggle Data Zone ON/OFF
<CTRL + E> Calls the Export TIFF dialog
<CTRL + F> Starts Auto Focus fine
<CTRL + SHIFT + F> Starts Auto Focus coarse
<CTRL + G> Switches SEM Control Panel ON
<CTRL + I> Switches SEM Status Panel ON
<CTRL + M> Switches to Annotation and inserts Point to Point Marker
<CTRL + O> Calls the Import TIFF dialog
<CTRL + P> Performs the Print Image function.
<CTRL + S> Performs Auto Astigmatism Correction
<CTRL + SHIFT + S> Performs Auto Astigmatism Correction with Auto Focus
<CTRL + T> Calls Text Annotation
<CTRL + V> Displays the Vacuum status information
Keypad <+> Faster Scan
Keypad <-> Slower Scan