Scanning electron microscopes Flashcards
1
Q
How does a SEM work
A
SEMs scan a beam of electrons across the specimen
This beam bounces off the surface of the specimen and the electrons are detected, forming an image
This means SEMs can produce three-dimensional images that show the surface of specimens
2
Q
Advantages of SEMs:
A
They can be used on thick or 3-D specimens
They allow the external, 3-D structure of specimens to be observed
3
Q
SEMs disadvantages
A
They give lower resolution images (less detail) than TEMs
They cannot be used to observe live specimens (unlike optical microscopes that can be used to observe live specimens)
They do not produce a colour image (unlike optical microscopes that produce a colour image)
4
Q
A
