No. There are too many other variables, such as electron emitter type, sample type, vacuum level, electron optics, emission current, beam current, condenser lens setting...
Dear Ian ,
THANKS. I KNOW BUT AS YOU KNOW IN THE UNDER SCANING ELECTRON MICROSCOPY IMAGES OFTEN THERE IS QUANTITIES SUCH AS magnification, accelerating voltage, working distance, and Resolution , SO IT IS INTERESTING FOR ME THAT KNOW RELATIONSHIP BETWEEN THEM BY FORMULA.
SO SEARCH THIS FORMULA .
REGARDS,
ABBAS
The single most powerful "knob" the user has to increase resolution is spot size.
Start your session at low magnification, large spot size and high scan rate to efficiently find what it is you are interested in. Then gradually increase magnifcation, reduce spot size and decrease scan rate.
If you drop too small in spot size the signal-to-noise ratio becomes too low to properly focus and stigmate on the target at a reasonable scan rate.
There are generalities that exist regarding the parameters and whether they will increase or decrease resolution, but each microscope is different and different samples require different parameters. For example in the FEG-SEM I could achieve a similar resolution on a gold/carbon specimen at 30kV at 5mm WD, as I could with a Si sample at 0.5kV decelerated at 1.5mm WD - a whole host of other parameters have to be varied as well. But if I put the gold/carbon sample in my W-SEM at 30kV 5mm the resolution would be worse, and the Si sample would not even produce an image.
It does not make sense to try and produce a formula to bring these together.
Dear Ian ,
please see page 135 of the book:Electron Microscopy and Analysis, Third Edition ,by Peter J. Goodhew , John Humphreys, Richard Beanland .
Abbas,
they are theoretical equations for an SEM of a given specification, as it says on p.140. These equations would not give the expected results in a different SEM. They are useful, however, to learn about the effect on one parameter as a result of varying another.
You might find these pages helpful
http://www.ammrf.org.au/myscope/sem/introduction/
An image in one of the SEM micrograph shows "S3400 15.0KV 67.3mm x 6 SE". Can anyone say me what does it mean ? How much magnification should I consider? shall i consider 6X as the magnification factor??
Binsu Babu Yes. S3400 is microscope model (here Hitachi S3400), 15 kV is accelerating voltage, 67.3 mm is working distance (WD), which by the way is very large (distance from pole piece where electrons enter chamber to your specimen) so my guess that together with very low magnification 6x is that it is an overview micrograph of the whole sample, whatever it is. Also, SE means it is from secondary electrons.
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