Jump to content

LabAdviser/314/Microscopy 314-307/Technique/Holo/Off-axis ETEM: Difference between revisions

← Older editNewer edit →
VisualWikitext
Jenk (talk | contribs)
DCH-Employees-701, NLAB-Employees-701, NLAB-LabmanagerAllUsers, NLAB-Nlab307-labadviser-users-34891
789 edits
No edit summary
Jenk (talk | contribs)
DCH-Employees-701, NLAB-Employees-701, NLAB-LabmanagerAllUsers, NLAB-Nlab307-labadviser-users-34891
789 edits
Line 26: Line 26:
# Insert your holder. First reset the holder such that the compustage is at x,y,z = 0,0,0, and both α and β tilt is at zero degrees. The insertion of the holder is similar to normal, by first parking the holder in the air-lock vent cycle (10min). Afterwards, rotate the holder to 12 o’clock and insert the holder slowly (the vacuum from the column will slowly pull it in)
# Insert your holder. First reset the holder such that the compustage is at x,y,z = 0,0,0, and both α and β tilt is at zero degrees. The insertion of the holder is similar to normal, by first parking the holder in the air-lock vent cycle (10min). Afterwards, rotate the holder to 12 o’clock and insert the holder slowly (the vacuum from the column will slowly pull it in)
# Find the specimen and ensure the beam is centered (Beam Alignment)
# Find the specimen and ensure the beam is centered (Beam Alignment)
# If needed (alignment is way off): Load the appropriate TEM alignment, e.g. 300 kV TEM. This is done by going to Alignment tabAlignmentFlapoutload the alignment file for the correct keV, e.g. Main_300kV. Select one particular alignment and the press Ctrl+A for selecting all and then move them from “Available” to “Selected” by clicking on the Apply button.
# '''If needed (alignment is way off)''': Load the appropriate TEM alignment, e.g. 300 kV TEM. This is done by going to Alignment tab → Alignment → Flapout → load the alignment file for the correct keV, e.g. Main_300kV. Select one particular alignment and the press Ctrl+A for selecting all and then move them from “Available” to “Selected” by clicking on the Apply button.
# If needed: Load the FEG register for TEM for the electron energy chosen in step 5 above. This is done by going to Gun tabFEG RegisterChoose the correct registerClick on Set
# '''If needed''': Load the FEG register for TEM for the electron energy chosen in step 5 above. This is done by going to Gun tab → FEG Register → Choose the correct register → Click on Set
# Make sure that the size of C2 aperture is set to 150 µm. Go to Mono tabApertureC2adjust and play with multifunctional knobs MFx and MFy on the left and right control panels for centering the chosen C2 aperture.
# Make sure that the size of C2 aperture is set to 150 µm. Go to Mono tab → Aperture → C2 → adjust and play with multifunctional knobs MFx and MFy on the left and right control panels for centering the chosen C2 aperture.
## lower C2 aperture can be used, however some of the beam is not passed through and can have an impact on the holograms.
## lower C2 aperture can be used, however some of the beam is not passed through and can have an impact on the holograms.
# Adjust the monochromator so that is does not interfere with the image
# Adjust the monochromator so that is does not interfere with the image
## Translational alignment of the monochromator: Go to the Monochromator panel click on shift and play with MFx and MFy to center the monochromator around the beam
## Translational alignment of the monochromator: Go to the Monochromator panel → click on shift and play with MFx and MFy to center the monochromator around the beam
## Strength of the monochromator: While in the monochromator panel, unclick the shift (yellow to grey) and click the focus button. Adjust the strength of the monochromator with the intensity (Mono = -30 -40 is usually the range).  
## Strength of the monochromator: While in the monochromator panel, unclick the shift (yellow to grey) and click the focus button. Adjust the strength of the monochromator with the intensity (Mono = -30 → -40 is usually the range).  
### The dose can further be reduced at lower Mono values, e.g. -100 or lower (adjust for different samples, however you need enough electrons to obtain good holograms. Test this when reconstructing if needed)
### The dose can further be reduced at lower Mono values, e.g. -100 or lower (adjust for different samples, however you need enough electrons to obtain good holograms. Test this when reconstructing if needed)
# Insert the OneView (CMOS) camera. Make sure the BM-Ultrascan is retracted. Go to the Oneview PC Microscope Display Click the Camera Icon “Insert”.  
# Insert the OneView (CMOS) camera. Make sure the BM-Ultrascan is retracted. Go to the Oneview PC → Microscope Display → Click the Camera Icon → “Insert”.  
# Open the display of the camera: Click TEM Imaging/Holography “View”
# Open the display of the camera: Click TEM Imaging/Holography → “View”
# Depending on the resolution, two different routes are needed. For medium resolution, I advice using Lorentz mode, which uses a weaker Lorentz lens and switches off the twin-pole object lens. For high-resolution, use the conventional HR-TEM mode.
# Depending on the resolution, two different routes are needed. For medium resolution, I advice using Lorentz mode, which uses a weaker Lorentz lens and switches off the twin-pole object lens. For high-resolution, use the conventional HR-TEM mode.
Retrieved from "https://labadviser.nanolab.dtu.dk//index.php?title=LabAdviser/314/Microscopy_314-307/Technique/Holo/Off-axis_ETEM"