A topic a bit off the beaten path, but relevant all the same; some clever chaps from the Michigan Technological University (MTU) have managed to create a transistor that doesn’t require the use of a semiconductor to conduct electricity. Why is that important? I’m glad you asked…
I’m no electrical engineer, but I know that without semiconductors and our development of silicon semiconductors, transistors would not be at the refined state that they are at now. The basic idea behind using semiconductors in transistors is that it allows a transistor to switch from a conducting state to an insulating state, and vice versa, using just an electrical signal; this is pretty much the basis for electronics as we know it, but as MTU physicist Yoke Khin Yap explains, 10 to 20 years from now, we will reach a physical limitation of how small transistors will be able to be made due to the semiconductor, which by and large are made of silicon.
However, according to Yap another MTU physicist, John Jaszczak, and their team, they’ve discovered a way to create a transistor that does away with the need for silicon semiconductors, which would open the door for even smaller transistors.
As Yap explains: “The idea was to make a transistor using a nanoscale insulator with nanoscale metals on top. In principle, you could get a piece of plastic and spread a handful of metal powders on top to make the devices, if you do it right. But we were trying to create it in nanoscale, so we chose a nanoscale insulator, boron nitride nanotubes, or BNNTs  for the substrate.â€
Too much information? I’ll let Mr. Yap break it down a little further: “Imagine that the nanotubes are a river, with an electrode on each bank. Now imagine some very tiny stepping stones across the river. The electrons hopped between the gold stepping stones. The stones are so small, you can only get one electron on the stone at a time. Every electron is passing the same way, so the device is always stable.â€
In this way, Yap and his team has managed to create a transistor without the need for a semiconductor and isn’t restricted by the physical limitations of a semiconductor like silicon; when a large enough voltage is applied, the transistor conducts, and when the voltage is low or zero, the transistor goes back to insulating. Perfect.
Furthermore, one big downside to silicon semiconductors is that they lose a lot of energy to heat making them quite inefficient, the phenomenon of which is called ‘leakage’. This technique of jumping electrons across gold dots is known as quantum tunneling and does away with the leakage seen in silicon semiconductors making this new transistor much cooler and avoids the energy losses due to heat.
This is extremely exciting stuff, and while it is only the first step to doing away with silicon semiconductors, the possibility of creating even smaller, more efficient transistors which would in turn allow even more transistors to be used in devices like smartphones has huge implications. This could mean a whole new age of computing and should be cause for huge excitement for the technology community.
I know I’m excited. Are you?
Source: MTU News via Overclockers Club
