/r/electronmicroscopy

Photograph via snooOG

A place to discuss all things electron microscopy including but not limited to:

  • Transmission Electron Microscopy (TEM)
  • Scanning Electron Microscopy (SEM)
  • Energy-dispersive X-ray Spectroscopy (EDS)
  • Electron Backscatter Diffraction (EBSD)
  • Electron Energy Loss Spectroscopy (EELS)

A place to discuss all things electron microscopy including but not limited to:

  • Transmission Electron Microscopy (TEM)
  • Scanning Electron Microscopy (SEM)
  • Energy-dispersive X-ray Spectroscopy (EDS)
  • Electron Backscatter Diffraction (EBSD)
  • Electron Energy Loss Spectroscopy (EELS)

Cool pictures are welcome as long as they are on topic. Questions, advice, and microscopy related discussions are most definitely encouraged.

/r/electronmicroscopy

2,583 Subscribers

4

HOW TO PREPARE FIBRE SAMPLES FOR SEM

As part of a project, I am required to study the microstructure of a fibre. I have searched the internet but couldn't find methods for specimen preparation for fibres. If you have any experience or knowledge regarding this , kindly help me.

Thanks in advance

7 Comments
2024/03/15
13:22 UTC

3

Refurbished Philips TEM on sale.

Hi we are a 25yo electron microscopy experienced company in EU, we have a refurbished CM in one of our facilities, it is working and I can show you pictures and videos. We are not using it and so we decide to sale it. We can properly prepare it for a safe shipping everywhere. Anyone interested?

2 Comments
2024/03/11
06:06 UTC

5

Beam Alignment on Zeiss Evo 10

Hey guys! Quick question

I've been working with a Zeiss Evo 10 for about a year now, this is my first time doing electron microscopy, my background is in materials engineering. The scope is a spectacular machine, full of capabilities, but i'm having trouble mantaining an aligned beam.

Depending on the operating conditions, (kV, Spot size, even magnification), when checking the emission image you can find the beam in various positions. Sometimes it needs a little touch up (easily fixable with the auto functions), sometimes you can't get an image and end up finding the beam is nowhere to be seen, and needs a full physical alignment of the apertures to get an image again.

We're on out third filament (the first blew out at 60 hours, aprently by user error), the second one was changed out at around 150 hours because it had been badly aligned and showed a strange distortion on its crossection on the sides. We're on the third one, at around 110 hours of use, and it should be aligned correctly.

As we keep pushing the limits of the scope, I find myself trying to "fight" the machine. We've had this conversation with tecnical support, and they say the scope has "auto calibration" functions, and that we should't worry about it, but in some cases it's quite difficult to get a decent image with a magnification of 5000X (10μ), even with metals at 20kV.

I understand that sample preparation could also be an issue, but for now it has been ruled out.

I'd love to hear from you guys, specially if you're working with some variation of this Zeiss product. I think a reference of how much can i ask from the microscope in any given scenario could be a lot of help. If there are any other questions or need more information, please let me know. Thanks!

4 Comments
2024/02/17
20:12 UTC

7

Cryo-EM softwares

Hi! I'm learning cryo-EM and I'm having a difficult time understanding how softwares like gctf and ctffind works. Can anyone please explain it in simple words? Thanks a ton!

3 Comments
2024/02/10
19:45 UTC

7

Is coronavirus spike protein visible on negative stain electron microscopy?

I have expressed native, and S2P stabilized spike protein in an eukaryotic expression system. I am trying to find an inexpensive assay to show that 2P substitution keeps the spike protein in a pre-fusion state. Could negative stain electron microscopy show the difference between S2P stabilized spike and native spike protein?

2 Comments
2024/01/27
22:49 UTC

3

Bio sample still charging even with a 8-14nm carbon coating, could it be section compression?

I image biological samples on grids on a FESTEM from Zeiss at 30kV.

We have a Frankenstein sputter coating/evaporating manual machine with finicky current controls. I use a carbon rod coating and have been getting anywhere from 8-14nm coatings. Even 23nm coatings don't help.

Previously imaged samplengrids hold up against the beam but these new sample grids will charge quickly and leave a black square on the sample instead of a normal white square.

Could it be due to my sections not always expanding when exposed to chloroform? It's a 99.999% purity but there is a lot of air space in the bottle now. Even on those that did expand charging is still present? What could it be?

7 Comments
2024/01/27
01:00 UTC

4

FEI Phenom

Hi all,

We received an old desktop SEM of FEI Phenom (gen 1) from a company. A couple of months ago, we could measure some samples. Then it was shut down for a couple of months. This week, we wanted to start it again and try to measure some samples.

However, after switching on the power supply with UPS the SEM won't start. We can hear the pre-vacuum pump working and making noise for approximately 1 min. We can see the light of the camera for 1 second.

According to the manual, the power light of SEM should be then on green, but we don't see any light.

The working of pre-vacuum and camera light let us know that SEM receives supply, so it is not on fuses.

The problem with this Phenom version is that Thermo Scientific is no longer supporting this version. I thought maybe some experts here could help us.

I hope a reaction to my first post on Reddit.

ibnhayyan58

7 Comments
2024/01/25
08:35 UTC

2

EBSD preparation for martensite steel

Has anyone experience in surface prep of martensite steel for EBSD? I've had good results with electropolishing, but can't use that currently, so I'm trying ion milling. Should around 6 kV be fine? Or would it be better to resort to vibration polishing with silica?

Edit: Solved. I did ion milling at 70 deg incidence (max with the setup I used). With 5 kV for 15 min, the surface was still rubbish. After 6 kV for 40 min, I got beautiful EBSD patterns! Thanks for your input!

7 Comments
2024/01/22
17:32 UTC

3

PhD in (S)TEM/Solid-state-physics - programming skills?

I want to do a PhD in (S)TEM/Solid-state-physics. The project is about imaging magnetic materials. I have no experience with TEM, do I need programming skills? My programming skills are not really good.

6 Comments
2024/01/21
05:34 UTC

7

Working Distances Using STEM.

Hello!

I have a question that has come up from users and I had to admit my naiveté. It involves the use of STEM and immersion mode on our Thermo Apreo 2S to image nanoparticles.

Will the image quality improve with smaller working distance or will it improve by lowering the stage closer to the detector? I know resolution would improve with the sample closer to the pole piece due to less beam divergence, but we'd see a decrease in signal reaching the detector. I'm sure it varies from application to application, but was curious if someone could share their experience.

Thanks!

12 Comments
2024/01/10
12:55 UTC

6

Gold sputter protocol for SEM

Can anybody share their sputtering protocols?

What is the suggested current, time and work distance for biological materials, mostly small invertebrates (Drosophila, Anopheles, Aedes, etc.) that were processes for SEM (fixed, dehydrated and critical point dried)

I am refurbishing an old Blazer - SCD 040 Sputter machine. I am having trouble standardizing a gold sputter protocol. For a 5nm thickness, the instructions suggest 15mA at a working distance of 50nm about 30secs. With this configuration I am still getting a lot of interference and charge-up when analyzing my samples. I played around with the settings and tried again but now the thickness is too thick and easily visible even at 30k mag. I know gold particles can be visible at around 45-60k mag, and I want to take images at around 40k mag.

Thick gold coating. Small particles are visible

Any help or suggestions would be greatly appreciated.

Interference caused by charge-up

8 Comments
2024/01/05
13:30 UTC

2

Reference mag for other brands besides Zeiss? Polaroid 055?

Hello everyone,

We have just found that our old reference magnification has been set incorrectly by the old technician. The Zeiss technicians have corrected it. They set it to 'polaroid 055' to resemble the old Polaroid print outs from before. However they explained that the reference magnification is only used for the image as shown on screen. Our automatic scalebar is always correct.

My question is what settings or reference magnification do your other brand instrument s use? Do you guys just go with default settings?

This will mean that all of our prior images have the incorrect magnification on them and that our paper will be incorrectly stating the magnification of our images.

Any and all help will be greatly appreciated.

1 Comment
2024/01/04
16:53 UTC

3

Old JEOL scopes maintenance

We have two old JEOL scanning electron microscopes (840 and 845A) which work great usually. We are looking for a company that would do maintenance contracts that which include PMs twice a year. As this scope is older JEOL no longer will service them and most of the people who worked on them when they were first in use are now mostly retired (to show how old the scopes are!) These scopes have stage automation and EDS attached to them. We use these scopes every day to look at various types of samples.

So far the places I have contacted either won't service the scopes, are in another country, or don't want to travel to where we are located (Upper mid-west USA). Does anyone know of anyone who may service these instruments? We are looking at one day upgrading to something newer but we need grants to do that.

6 Comments
2024/01/03
19:40 UTC

3

Where do you get the consumables from?

Which supplier is everyone using?

9 Comments
2023/12/08
06:11 UTC

1

Identifying Source of Noise.

13 Comments
2023/12/07
23:24 UTC

4

Register SEM for hobbyist use

Hi, it is a lure to own an out of date SEM as a hobbyist, the price is sometimes cheaper than an old car. But in US, some state require to register the SEM to radiation office. Is it possible to register it use a residential address, my garage? Because of the thick wall,,We know the x ray radiation even at 30KV from SEM is close to the background noise. Do the register require some shielding for your house placing the SEM? How much fee to pay annually for your register?

Thanks

Free-electron

4 Comments
2023/12/07
19:38 UTC

3

FIB/SEM and STEM work

With experience in FIB work and STEM, I was wondering if anyone needs any work done with these techniques? Whether you have your own tools or not, I would be interested to help out with preparation and imaging. Might be a shot in the dark, but please let me know if you need any help with these techniques. Thank you!

4 Comments
2023/12/06
01:39 UTC

1

Edge Detection for counting on SEM images

6 Comments
2023/11/21
13:28 UTC

5

Need help fixing oval-shaped beam align on Hitachi S4700 SEM

Recently our SEM has been having beam align issues even when the aperture and stigma aligns are set properly. I haven’t been able to find a setting in the software to make the beam align more circular. How do we fix this? Is this something we can fix ourselves or would it require a technician to service the SEM?

5 Comments
2023/11/15
19:37 UTC

3

Sample previously poorly sputter coated with gold, options to improve coating?

I will be receiving a sample that was previously poorly coated with maybe 3nm of gold. What would be some options to improve the coating? What would the result be if I were to carbon coat over the existing gold coat?

1 Comment
2023/11/06
15:19 UTC

2

Finding flaws/mistakes in research papers having SEM images.( Can be mistakes in evaluation of SEM)

Hi everyone! I got an assignment where I have to find a paper in which there are mistakes in SEM image (technique) or we are not getting the complete information i.e. there is some ambiguity in the interpretation/ evaluation of the data. Are there still questions that remain unanswered. Did the authors discuss the data for technique fully? Also, if there is some ambiguity in the acquisition/synthesis/preparation of the data for SEM. I am very new to this technique. Plus, how to critique it is difficult for me at this level. It has to be of RSC/ACS/Wiley from past 5 years only. Please help!!

2 Comments
2023/11/05
18:38 UTC

6

Fast and lossless compression

Hi all. We all have a problem with handling high amounts of data being generated with novel detectors. Me and my supervisor designed a fast and lossless compression algorithm for diffraction and cryo-EM data and released the code under MIT license. Would be happy if you could test and share your thoughts. In our case we could compress up to 2000 frames of 512 by 512 16-bit diffraction data in just one second and using one core of the laptop. Here is the paper: https://scripts.iucr.org/cgi-bin/paper?S205327332300760X

0 Comments
2023/10/28
15:39 UTC

4

FIB lithography of Aluminium nanostructures

Hey guys, I have this pickle I am struggling with for few weeks now and I would appreciate any advice.

I am trying to fabricate plasmonic antennas by SEM/FIB out of 30 nm Al layer deposited on 50 nm thick SiNx TEM membrane substrate. So far I have been struggling due to the low sputtering yield of aluminium. The problem is that due to the sputtering yield of SiNx being higher than aluminium's, before the aluminium is removed (even the residual grains etc), elsewhere in the milled area, the SiNx membrane gets already removed and there is a punctured hole in the membrane, which then messes up the EELS measurement in STEM. Has someone had the honour of nanostructuring Al films? And would you please give me any advice how to solve the issue? Perhaps different milling strategies of the FIB beam would solve the issue?

9 Comments
2023/10/11
20:21 UTC

15

The Open-source Scanning Electron Microscope Project

Hello there, sorry for not posting an update for a long time. I have made progress with building the DIY SEM, I am planning to start an Open Source Scanning Electron Microscope Project and am open to collaborate, I am receiving funding for materials and am given the equipment needed by a local college. Please DM me or mail me at meshnet31@gmail.com if interested.

6 Comments
2023/10/02
12:29 UTC

2

Electron Tomography Facilities?

I have a project that may need to incorporate electron tomography. I have tried to see what facilities are available with that equipment for collaboration but have not had much luck finding one. Does anyone know of a facility/university with that equipment? Preferably in California or the west coast (U.S.)

15 Comments
2023/09/26
18:27 UTC

2

Another job opening in biological EM

0 Comments
2023/09/22
21:41 UTC

7

SEM Recommendations

We're planning to buy a SEM for our glass research facility. Torn between having a desktop and floor type. Currently looking at Hitachi, Jeol and Thermofisher. What are your thoughts and recommendations?

29 Comments
2023/09/21
10:17 UTC

1

Third-Party EDS Repair

I am wondering if anyone knows of a third-party or independent electronics business that could repair my ca. 2010 Ametek/EDAX Apollo X EDS SSD detector?

Edit: I’m in the US

3 Comments
2023/09/13
18:43 UTC

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