Scanning Electron Microscope Images

[pandasarecute]

Would the resulting image by a scanning electron microscope be different if it scanned across the y-axis?

SEMs have deflecting coils that move the electron beam from left to right (x-axis) rapidly while traversing down the y-axis to cover the entire specimen.

Would the image you get after be different if it was moving the beam from up to down (y-axis) while slowly moving from left to right?

 

[QianCao227]

I think they are the same. You could try testing it by rotating the sample 90 degrees to see if you still get the same image. That's what my lab does with the AFM.

 

[K^2]

It could be. It really shouldn't be, but there are a whole lot of things that could be going on, from control systems not being perfectly in tune, to any small changes to the sample while you're scanning. For example, if the sample is heating/cooling while the scan is in progress, the expanding/shrinking of the sample will have different effect on the image depending on whether you're scanning in x or y direction.

I've never used an electron microscope, but I've played with a scanning tunneling microscope, and you could clearly see scan-lines on the final image, simply due to the way that z-hold circuit responded to changes in tunneling current.