Researchers at TU Wien have Developed Adaptive Transistor Using Germanium

Transistors as we know them appear to be in for a big change, at least if the latest development by researchers at TU Wien has anything to say about it. The group of researchers have developed what they call an adaptive transistor, or in other words, a transistor that can do more than hold a 0 or a 1. This has huge implications and although they’re currently at a very early stage, the working proof of concept could allow for a whole new range of applications for microchips.

It would appear that the new transistors are tricky to manufacture, based on the explanation by the researchers “We connect two electrodes with an extremely thin wire made of germanium, via extremely clean high-quality interfaces. Above the germanium segment, we place a gate electrode like the ones found in conventional transistors. What is decisive is that our transistor features a further control electrode, which is placed on the interfaces between germanium and metal. It can dynamically program the function of the transistor”. The researchers are confident that this should be fairly straightforward to overcome, especially as their transistor doesn’t require any “doping”, something that is common with more complex transistors today.

Manufacturing issues aside, the new transistors are expected to be able to change between different types of traditional transistor types on the fly, courtesy of its unique design. “This is because germanium has a very special electronic structure: when you apply voltage, the current flow initially increases, as you would expect. After a certain threshold, however, the current flow decreases again – this is called negative differential resistance. With the help of the control electrode, we can modulate at which voltage this threshold lies. This results in new degrees of freedom that we can use to give the transistor exactly the properties that we need at the moment.”

The scientists believe that this would allow for fewer transistors in some applications, while at the same time, saving power and gaining performance. “Arithmetic operations, which previously required 160 transistors, are possible with 24 transistors due to this increased adaptability. In this way, the speed and energy efficiency of the circuits can also be significantly increased.” The longer term hope is that we’ll get to a point where the transistors can adapt by themselves as needed, assuming the right AI can be developed to take advantage of these new transistors.

These new transistors aren’t set to entirely replace the traditional transistors we use today, but should apparently be seen as a compliment, somewhat in the same way that FPGA’s can’t replace traditional processors, but are more and more seen as a compliment for certain applications. There are many applications where an adaptable processor on the fly can come in handy and if this project can be commercialised, it will likely be implemented in everything from simple MCU’s to advanced server processors. “Some details still need to be optimized, but with our first programmable germanium transistor we have proved that the basic idea really works. This is a decisive breakthrough for us”.