Friday June 14, 2013
Here’s carbon tape putting on a show again.
This is the most commonplace part of scanning electron microscope imaging - and in my opinion, one of the most consistently cool-looking. We use carbon tape because it’s conductive, and stops electric charge from building up on the samples we’re looking at - it give the charge somewhere to go. If charge builds up, it ends up deflecting the electrons that we’re trying to bounce off our sample, so the electrons never bounce back to our detector. The result? "Charging", a phenomenon where your sample rather spookily goes gradually dark. And begins to try to escape - the image goes skittering darkly across the screen, and trying to take a decent image requires a determined chase, and some luck with the timing. So conductive carbon tape is our friend. And did I mention that it looks pretty cool?