Yes, my mistake, it was indeed the pole piece. Not something that’s supposed to be in close proximity like with an AFM. If I had broken an AFM tip it would’ve been less of a problem, because those are expected to wear out every so often.
It was a few years ago, but I remember that we were doing e-beam lithography, and that did make it necessary to move the stage around. I think the idea was that our circuit was pre-drawn using software, after which we could just put the diagram into the SEM computer and it would scan around and draw the pattern we wanted. But in order to set this up, it was necessary to precisely locate the initial position of the stage in (x, y, z) so that our pattern would be drawn at the correct location on the silicon. And this meant we had to actually move the stage around, instead of just using the optics to focus on different parts. And due to things like differences in the wafer housing thickness, and other users who had moved the stage, that included moving it up and down.
ETA: All this was done before turning on the electron beam itself, since that would’ve started burning up the resist. The initial setup was done using a low-power optical microscope inside the SEM.
Yes, my mistake, it was indeed the pole piece. Not something that’s supposed to be in close proximity like with an AFM. If I had broken an AFM tip it would’ve been less of a problem, because those are expected to wear out every so often.
It was a few years ago, but I remember that we were doing e-beam lithography, and that did make it necessary to move the stage around. I think the idea was that our circuit was pre-drawn using software, after which we could just put the diagram into the SEM computer and it would scan around and draw the pattern we wanted. But in order to set this up, it was necessary to precisely locate the initial position of the stage in (x, y, z) so that our pattern would be drawn at the correct location on the silicon. And this meant we had to actually move the stage around, instead of just using the optics to focus on different parts. And due to things like differences in the wafer housing thickness, and other users who had moved the stage, that included moving it up and down.
ETA: All this was done before turning on the electron beam itself, since that would’ve started burning up the resist. The initial setup was done using a low-power optical microscope inside the SEM.