The explosion of electronics over the past several decades has been incredible; unimaginable even. If you had told computer scientists working with giant knobs on computers that filled an entire room that in just 50 years people would be downloading gigabytes of information from the sky on palm-sized telephones millions of times every single day, well, they’d probably believe you. But they’d be jealous as hell while waiting hours for their behemoth to figure out a single derivative.
Every single year – hell, every single week it seems – our technology gets smaller and faster. And it seems to be increasing at an exponential rate. At some point, scientists are going to figure out how to make computers using quantum mechanics rather than electrical circuits, but not yet. Until that time, there has to be a limit to how small and how fast we can make electronics on a silicon wafer. Surely, there must be a time when we’ve reached the edge of what is physically possible. And surely we must be coming up on that point.
But we’re not there yet.
Case in point, a new paper from the University of Wisconsin’s Say-That-Five-Times-Fast Chang Beom-Eom published in Nature Communications details a new way to use oxide gases and electron guns to draw nano-sized wires with the precision of single atoms.
An oxide is any compound that has oxygen atoms as a major component and there are literally millions of different combinations. And because of their electron shell structure, most of them are candidates for being important to the world of nano-electronics. However, all of these compounds have different molecular structures than silicon, making it nearly impossible to bind them together.
True, you potentially could use a substance other than silicon to create oxide electronics, but when an entire multi-billion dollar industry is using silicon wafers and chips already, it’s probably a good idea to stick with what’s already out there. Nobody wants to build an entirely new computer manufacturing infrastructure. It’s the same reason that car engines aren’t made out of ceramics instead of metal.
However, Eom has found a way around the issue to put three-atom-thick layers of electronically capable oxides onto silicon wafers. What’s more, he has shown that these oxides can be drawn on with an electron gun on a nanometer scale, with single atom precision, and that it can then be erased and drawn again.
It’s almost like a child breathing on a cold window and drawing on the fog, except that for the scale to be correct for a one-inch microchip, the window would have to be 200 miles wide.
So you want specifics, you say? Alright.
The new process allows the placing of three-atom-thick layers of lanthanum-aluminum-oxide in contact with strontium-titanium-oxide and then putting the entire structure on top of a silicon substrate. The interface of these two compounds creates an “electron gas,” which can be drawn on by an electron gun. The two oxide compounds must be totally pure, their crystalline structures must be matched exactly and the resulting sandwich must be tuned to the silicon wafer.
I’m sure all of that is even more difficult than it sounds. However, I do believe that the final incredible steps of high-density electronics have yet to be taken. This is going to be big. Um, I mean small. Really small.