This is about as interesting as pointing out the fact that an ultrasound picture of a baby isn't an "actual picture", since we use sound instead of light to make the image.
The first one was built in 1981, but one could have been built in the 1950s. Piezoelectric crystals were known. Raster scanning circuits were known. Feedback circuits for controlling the height were known. The tricks for making one-atom sharp points were not known, but the earliest STMs just stretched out a tiny platinum wire until it broke, and sometimes you got a one-atom point.
Hobbyists have built STMs. It's simpler than building a 3D printer.
For really cool stuff, check out the CO functionalized tip AFM coming out of IBM in Zürich: https://www.zurich.ibm.com/st/atomic_manipulation/pentacene....
The AFM I used was mainly for teaching the concepts, so they wanted simple, cheap, low risk => strong NaOH was out.
The technique back then was, somehow, cutting at about 45° angle and twisting the pliers to make this angle go to zero while cutting/pulling. Then you had to put the tip in the machine and do test images to see whether the tip was good. Usually it wasn't, so you tried again. Finally you got a perfect tip, and maybe got two or three good images before you messed up the tip (from being a noob).
Getting pictures of atoms is nice, but sometimes you want to image molecules, especially organic ones (tricky to do in a STM).
Also, what would the shape of the tip look like if you drew it? I'm wondering what kind of general angles the surface has. Is it like a cone with a single atom at the tip? What kind of slope?
A good tip could be just about anything, from a nice cone to really jagged. One problem was any of the methods one has to view the tip can't actually resolve the single atom that is doing the imaging.
Dumb question .. I get that the needle scans a surface and you get the quantum tunneling effect between the atom you are "looking at" and the tip of the needle. What I don't get is how one figures out depth. For each X,Y position, do you just keep going down until you touch something, and then move up, and go to the next position? If so, apart from the issue with 1 atom tip, I imagine the next problem would how to increment X and Y by 1 atom.
P.S. I think some of the marketing put out on these things really confuses the issue. Sure .. it gets people excited about science but it gives people the wrong intuition. As a non-physics person, I got a lot out of this article.
This means that you're getting a "pseudo-height" map - if you had a surface with 2 types of atoms, both the same size, but with different tunneling barriers, you would see them appear to be different sizes.
High RF gains are easier to get than DC gains; you can filter out everything but the frequency of interest and reduce noise. That's basically how radios amplify weak signals. But I don't think you can run an STM on RF.
Ultrasounds also are pictures, but not photographs.
 https://physics.aps.org/featured-article-pdf/10.1103/PhysRev... (open access)
I do know how an ultrasound image works, and I had some basic knowledge about scanning tunneling microscopes, but this article - and the many links in it - were definitely worth my time reading.
I'm also curious -- but I wonder, would this allow for imaging anything that a scanning electron microscope can't?
Also, I think they were analog chips, not digital. I'm not sure. This was a co-op job in my first year at college at the IBM plant on Cottle Road, and I was never fully in touch with the big picture. I think they were making big-ass hard drives, and the chips I was working on were part of the circuitry that amplified the raw signal from the read-write head, but those details were way above my pay grade.
It was an MCU, which many might call a SoC these days, but with all the timers and serial i/o and the A/D and D/A converters and PWMs - the 8-bit family (HC11) was probably around 50K transistors in an 80-pin QFP.
The HC11 had a 6809(enhanced) core. I think the 6809 was ~9K transistors, but I seem to recall that ours was a bit bigger than that. Still ~3/4 of the die was "not-CPU".
Also be sure to check out IBM's STM gallery for some more amazing images.
A beautiful symbol of prowess, intelligence, creativity and humanity. I don't think anyone should underestimate the impact that a video like that can have on a child (or even a curious adult!)
Say, a dolphin's echolocation might let him "see" a diver using sound - http://i.imgur.com/CS6wkNV.png , which would still be considered an image, even though it's using sound.
Anyway that's just semantics, and an STM is still a damn impressive piece of kit.
What's with the synthesizer hate? That seems random.
Some people feel very strongly that sound should only be produced by natural (non-GMO) organic means, such as rubbing horsehair on catgut, banging sticks on skins or yelling painfully loud.
They're still sore about Moog.
(He was pulling your leg, and so am I. Mostly. Synthpop ... well, least said, soonest mended.)
Knowing DNA was helical from the fiber diffraction images (not crystallography- they were working with DNA fibers, not crystals) was actually "obvious". A helix forms a distinctive cross pattern, this can be (and was) predicted easily from diffraction theory applied to a helical structure.
How To Make Something One Atom Thick
A great example is people who "discovered" lost cities under the sea. They saw regular patterns of lines on the seafloor in Google Earth and interpreted them as ancient roads or walls. But they were only seeing artifacts from ships that had sailed back and forth in straight lines collecting data. If they had looked both at those sonar scans and some other data for the same location, they would have only seen the lines on one image and been able to conclude that they were either an artifact of the sonar or below the level of sensitivity of the other instrument.