An important breakthrough in transistor technology has been achieved at TU Wien: With the help of novel insulators, high-quality transistors can be produced using two-dimensional materials.
For decades, the transistors on our microchips have become smaller, faster and cheaper. Approximately every two years the number of transistors on commercial chips has doubled – this phenomenon became known as “Moore’s Law”. But for several years now, Moore’s law does not hold any more. The miniaturization has reached a natural limit, as completely new problems arise when a length scale of only a few nanometers is approached.
Now, however, the next big miniaturization step could soon become possible – with so-called “two-dimensional (2D) materials” that may consist of only a single atomic layer. With the help of a novel insulator made of calcium fluoride, scientists at TU Wien (Vienna) have created an ultra-thin transistor, which has excellent electrical properties and, in contrast to previous technologies, can be miniaturized to an extremely small size. The new technology has now been presented in the journal “Nature Electronics”.
Ultra-Thin Semiconductors and Insulators
Research on semiconductor materials needed to fabricate transistors has seen significant progress in recent years. Today, ultra-thin semiconductors can be made of 2D materials, consisting of only a few atomic layers. “But this is not enough to build an extremely small transistor,” says Professor Tibor Grasser from the Institute of Microelectronics at TU Wien. “In addition to the ultra-thin semiconductor, we also need an ultra-thin insulator.”
This is due to the fundamental design structure of a transistor: current can flow from one side of the transistor to the other, but only if a voltage is applied in the middle, creating an electric field. The electrode providing this field must be electrically insulated from the semiconductor itself. “There have already been transistor experiments with ultra-thin semiconductors, but until now they were coupled with ordinary insulators,” says Tibor Grasser. “There is not much benefit in reducing the thickness of the semiconductor when it still has to be combined with a thick layer of insulator material. There is no way of miniaturizing such a transistor any further. Also, at very small length scales the insulator surface turned out to disturb the electronic properties of the semiconductor.”
Therefore, Yury Illarionov, a postdoc in Tibor Grasser’s team, tried a novel approach. He used ultra-thin 2D-materials not only for the semiconductor part of the transistor, but also for the insulating part. By selecting ultra-thin insulating materials such as ionic crystals, a transistor with a size of only a few nanometers can be built. The electronic properties are improved because ionic crystals can have a perfectly regular surface, without a single atom protruding from the surface, which could disturb the electric field. “Conventional materials have covalent bonds in the third dimension – atoms that couple to the neighboring materials above and below,” explains Tibor Grasser. “This is not the case in 2D materials and ionic crystals, and so they do not interfere with the electrical properties of the semiconductor.”
The Prototype is a World Champion
To produce the new ultra-thin transistor, calcium fluoride was selected as the insulating material. The calcium fluoride layer was produced at the Ioffe Institute in St. Petersburg, where the first author of the publication, Yury Illarionov, is originally from before joining the team in Vienna. The transistor itself was then manufactured by Prof. Thomas Müller’s team at the Institute of Photonics at TU Wien and analyzed at the Institute for Microelectronics.
The very first prototype already surpassed all expectations: “For years, we have received quite a number of different transistors to investigate their technical properties – but we have never seen anything like our transistor with the calcium fluoride insulator,” says Tibor Grasser. “The prototype with its superior electrical properties outshines all previous models.”
Now the team wants to find out which combinations of insulators and semiconductors work best. It may take a few more years before the technology can be used for commercially available computer chips as the manufacturing processes for the material layers still need to be improved. “In general, however, there is no doubt that transistors made of 2D materials are a highly interesting option for the future,” says Tibor Grasser. “From a scientific point of view, it is clear that the fluorides we have just tested are currently the best solution for the insulator problem. Now, only a few technical questions remain to be answered. ”
This new kind of smaller and faster transistor should enable the computer industry to take the next big step. This way, Moore’s law of exponentially increasing computer power could soon come to life again.
Learn more: Ultrathin Transistors for Faster Computer Chips
The Latest on: Ultra-thin transistor
[google_news title=”” keyword=”ultra-thin transistor” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Ultra-thin transistor
- New phononics materials may lead to smaller, more powerful wireless deviceson May 9, 2024 at 2:23 pm
What if your earbuds could do everything your smartphone can do already, except better? What sounds a bit like science fiction may actually not be so far off. A new class of synthetic materials could ...
- “Magnetisation switching” can replace transistors, cutting energy demand from computing by an order of magnitudeon May 1, 2024 at 12:00 am
Globally, energy demand from computing is growing so fast the search is on to find fundamental ways to make it more efficient. “Magnetisation switching” has long been seen as a more efficient way than ...
- When Does a Conductor Not Conduct?on April 30, 2024 at 5:00 pm
This material’s ability to act as an efficient ‘switch’ makes it a promising candidate for application in new electronic devices such as transistors. The atomically thin (or ‘2D ... that could be used ...
- A better amorphous p-channel thin-film transistoron April 25, 2024 at 5:00 pm
Scientist in Korea are making fast p-channel amorphous thin-film transistors. “Research progress on p-type amorphous semiconductors has been notably sluggish,” according to the Pohang University of ...
- Opening up the potential of thin-film electronics for flexible chip designon April 23, 2024 at 5:00 pm
The mass production of conventional silicon chips relies on a successful business model with large 'semiconductor fabrication plants' or 'foundries'. New research by shows that this 'foundry' model ...
- 2D transistors can mimic a locust's brain to avoid collision— super-efficient tech could lower the energy costs of tomorrow's AIon April 22, 2024 at 10:46 pm
Researchers have created an ultra-low power 2D transistor to ... able to be duplicated by scientists with incredibly thin two-dimensional transistors, which also produce spikes analogous to ...
- Apple Watch Series 10 could use new display technology with this key benefiton April 9, 2024 at 4:06 pm
The rumor comes from The Elec, which reports that the Apple Watch Series 10 will use an upgraded OLED display with low-temperature polycrystalline oxide (LTPO) thin-film transistor (TFT ...
- Transistors explained – what they are and what they doon October 24, 2022 at 11:53 am
The transistors on microchips are made by building up layers of interconnected patterns on a silicon wafer. This manufacturing process is a highly intricate undertaking involving hundreds of ...
- New ultra-thin semiconductor could extend life of Moore’s Lawon November 21, 2016 at 8:27 am
Importantly, unlike graphene but similar to silicon, ultra-thin InSe has a large energy gap allowing transistors to be easily switched on and off, allowing for super-fast next-generation electronic ...
via Bing News