Reconfigurable "Electrostatically Doped" Transistors Could Mean Smaller, More Efficient Chips
By replacing point-of-manufacture atomic doping with electrostatic doping, these clever transistors can learn new tricks on the fly.
Researchers from the TU Vienna Institute of Solid-State Electronics and the Swiss Federal Laboratories for Materials Science and Technology have come up with a trick to reducing the footprints of modern microchips without sacrificing functionality: intelligent, controllable transistors for reconfigurable electronics.
"Unlike in conventional semiconductor technology, the logical operation of a particular circuit is not determined from the outset. We can reconfigure the function of a circuit according to our requirements," Masiar Sistani, PhD, explains of the team's work. "For example, you can make an addition circuit out of two very compact XOR [Exclusive OR] links using our technology. With conventional technology, you would have to produce two different circuits for these tasks and therefore take up a lot more chip area; with our technology, one can do both."
The trick lies in unusually flexible transistors, which do not need to be doped through the introduction of specific materials during the fabrication process but can be "electostatically doped" at will through the presence of an additional electrode. By switching the properties of the transistor, its behavior can be influenced — something that, in a traditional chip, can't be achieved after the fabrication stage.
Using these transistors, the team suggests, the number of components in a leading-edge chip can be reduced along with its footprint. The technology could also deliver efficiency and performance improvements, too. "In today's chips, you have different blocks that can perform very specific tasks," explains first author Lukas Wind.
"You have to constantly send information from one block to another. That takes time and costs energy." With the reconfigurable transistors, the same information could be processed in one place on the chip by changing the transistors' functionality on-the-fly.
"There is a lot of interest," claims Walter Weber, TU Vienna professor, of the semiconductor industry's reaction to the team's work and its potential for commercialization. "Of course, this is a significant step that cannot be implemented from one day to the next. But our approach does not require any new materials or processes; we use silicon and germanium, materials that are also used today."
The team's work has been published in the journal IEEE Transactions on Electron Devices under open-access terms.