Performing STEM alignment using the Ronchigram

[@Sbuda22]

Nick, great job. Thank you. I will be doing imaging on a probe and image corrected microscope and your video has given me a bit of confidence.

[@NicholasRudawski]

You're welcome; just be aware that Ronchigrams look a lot different in a Cs corrected instrument. We just acquired one here so once it is up I'll have to make a video about alignment with a Cs corrected STEM.

[@dianchenggeng4739]

Hi, Nick, thanks so much for your sharing. I pretty enjoy your video!

[@NicholasRudawski]

Hi Diancheng: you're welcome, glad you enjoy my videos!

[@aravindabhat8813]

Hi Nick , how to adjust the tilt ( which button we need to activate to adjust the tilt , ) and what is the use of Rotation objective and rotation Intensity options in STEM alignment

[@tingjuly9253]

Thanks so much, I learned a lot from your detailed explanation. It will be better if you can put the image of corresponding operation buttons

[@NicholasRudawski]

Hi Ting, glad you found it useful; please see this video I did with the Talos: kzbin.info/www/bejne/ZmGri4J3h6yHj6M It's not the same S/TEM in the Ronchigram video (that was a JEOL 2010F), but I do go over what knobs/settings I'm adjusting.

[@ShivaShukla4u]

Hi Nicholas, very nice and informative videos you have. Can you share a video on image diffraction pattern rotation calibration.

[@NicholasRudawski]

Thank you; doing a video on rotation calibration is a great idea, I will do that for my next video.

[@RottenStrawburry]

Hi, Nike. Can I ask why the area choose should be amorphous?

[@NicholasRudawski]

Hi Shao: if the sample is crystalline it is much harder (though not impossible) to check that the expansion/contraction is concentric; you also will not see any rings, so it will be harder (though, again, not impossible) to correct the astigmatism. Amorphous is just much easier.

[@aravindabhat8813]

Hi Nick , how to adjust the tilt ( which button we need to activate to adjust the tilt , ) and what is the use of Rotation objective and rotation Intensity options in STEM alignment

[@NicholasRudawski]

Hi Aravinda: to activate the tilt, it depends on what microscope you are using. Are you using an FEI S?TEM? If so, you have to select rotation center from the direct alignments list and then the multifunction knobs will control beam tilt (this will be the same regardless of choosing rotation center (objective) or rotation center (intensity). If you are not using an FEI S/TEM, what S/TEM do you have? On the JEOL 2010F used in this video, I seem to recall the tilt control was not named something very obvious.

[@jessieq8720]

@@NicholasRudawski Hi Nick, thanks for the videos which are extremely helpful! Since you mentioned here, would you mind explaining what's the difference btw rotation center (objective) and rotation center (intensity)? Thanks again!

[@NicholasRudawski]

@@jessieq8720 Hi Jessie: sorry for the late reply, and glad you find the videos helpful. When you select either of the "rotation center" options, your MF knobs control beam tilt, so in this sense the options are identical. The only difference between the two options is what is being wobbled. If selecting the "intensity" option, the C2 lens is wobbled, while if selecting the "objective" option, the objective lens is wobbled. Since I deactivate the wobbling when doing this alignment and then manually wobble the C2 lens with "Focus", you could use either option and the result would be the same. I hope this helps.