WHY THIS MATTERS IN BRIEF
As silicon based transistors, the bed rock of today’s modern computing platforms, near their theoretical limits we will see the birth of several new types of computing platforms that will dominate the decades to come.
We are always being told that Moore’s Law is breaking, but increasingly today it’s breaking not because we’re at the technical limits, for example researchers recently demonstrated their latest 1nm transistor and virus sized computer architectures, but because we’re at the economic limit because every time the chip manufacturers step down a size it costs them anywhere between $15Bn to $30Bn in new investment.
Now, to demonstrate the point, a team at Columbia University have taken another big step on the road to creating atomically precise, reproducible transistors made from single molecules that can operate at room temperature, and the breakthrough will be a major milestone in helping us realise a new era of molecular electronics. Or to put it another way, an era of molecule sized electronics.
The team created a two-terminal transistor with a diameter of about 0.5 nanometers and a core that consisted of just 14 atoms, and the device can reliably switch from insulator to conductor when charge is added or removed, one electron at a time, something known as a “Current blockade.”
The research was published in the journal Nature Nanotechnology.
“With these molecular clusters, we have complete control over their structure with atomic precision and can change the elemental composition and structure in a controllable manner to elicit certain electrical response,” says Latha Venkataraman, leader of the Columbia research team.
Now, as a follow up step the researchers plan to design better and improved molecular cluster systems with better electrical performance, such as higher on/off current ratio and different accessible states, and increase the number of atoms in the cluster core, while maintaining the atomic precision and uniformity of the compound.
Elsewhere other studies into creating atomic scale and molecular scale transistors have used Quantum Dots, nanoscale semiconductor crystals of nanometre dimensions with distinctive conductive properties that are determined by its size, to produce similar effects, but the dots are much larger and aren’t uniform in size making it a problem to reproduce them in a repeatable manner – something that’s crucial if the technology is ever going to be mass produced.
All this said though the ultimate size reduction for any transistor would ultimately be transistors made up of just a single atom, which would mean they’re less than 0.1nm in size, but at the moment using current technology they’d require ultra-cold temperatures of -196C in order to cancel out some of the electronic “leakage” effects which, at the moment, cripple the technology.
As for what comes next, when we hit the maximum theoretical limit of Moore’s Law, in other words transistors that are only one atom in size? Well, this is where we will then start to see computing “branch” into new forms with not one but many new forms of computing platform emerge such as Chemical Computing, DNA Computing and Molecular Computing, which could be both, for example, be built using the incoming breed of Molecular Assemblers, and the current leader of the pack Quantum Computing… In the future computing platforms won’t be silicon based, and they won’t be “one” type, they will be ubiquitous, and varied.
Get ready for the next revolution.