Competition for new materials: Silene overcame graphene?

Siliconene is considered to be more than graphene in future applications in electronic components. A few days ago, a team of Italian and U.S. researchers created the world’s first silicon-based transistor. This result will speed up the practical application of silicon.

Siliconene is a material made of single-atom-thick silicon, similar to graphene, which has been shown to have excellent electrical conductivity, but the preparation process is extremely difficult. This kind of transistor has enormous potential. For computer scientists, siliconene is a more interesting material than graphene. Seven years ago, silylene was only a dream for theorists. Driven by graphene heat, researchers speculate that silicon atoms may also form similar surfaces. And if they can be used to make electronic products, silicon film will enable the semiconductor industry to realize the ultimate dream of miniaturization.

Currently, the research team plans to refine the manufacturing process in order to produce longer-lived silicon-based transistors in the short term. There are still many difficulties that need to be overcome because silylene is very unstable when used in the real world, but scientists said: “This is a major breakthrough, and the first time that low-temperature manufacturing technology and silicon olefins are manufactured.” Researchers believe The application of siliconene in future electronic components will be easier than graphene. After all, the vast majority of chip designs are silicon-based.

Deji Akinwande, a nanomaterials researcher at Texas State University who is involved in making this transistor, said that although the performance of the device is still relatively common and the lifetime can only be measured in minutes, the confirmation of this concept has attracted much attention. Guy Le Lay, a materials scientist at the University of Marseilles in France, agreed with him. "No one expects to realize it in such a short time. After all, it is impossible to make a transistor from a material that does not exist at all," he said.

However, there has always been a huge challenge in the processing of silicon olefins in the laboratory. This kind of material cannot form blocky graphite like graphene, and then it is peeled off from the solid block with tape. Instead, the researchers acquired it by concentrating the silicon atom hot vapor in a vacuum chamber onto a transparent block of silver, which is a very complicated process. And unlike robust graphene, the individual siliconene is extremely unstable in the air and it is difficult to coat a light and thin surface on a more useful substrate, such as the inner wall of a transistor. Because of this, until last year, some researchers still questioned the existence of silylene.

As siliconene transistors go into reality, there is an increasing awareness that graphene is not suitable for transistor fabrication. Graphene is perhaps the best conductive material in the world, but it lacks a key feature. Unlike semiconductors used in computer chips, it lacks band gaps—the energy hurdles that electrons must jump through before they carry current. Bandgap allows semiconductor devices to shut down and perform "logical" operations.

In contrast, siliconene has a band gap. However, this kind of transistor can't be applied to the mobile phone in the short term: Because the exposed siliconene will degenerate in about 2 minutes. However, this time is enough to detect its characteristics. If you add a layer of coating on the silane transistor can extend its life. Akinwande had used PTFE to help phosphene film “live” for months.

However, not everyone is optimistic about the future of siliconene. “Now, there are many discussions about siliconenes, terpenes, and phosphenes. But they have a lot of problems.” Jari Kinaret of Chalmers University of Technology in Sweden said that he is also the head of the EU flagship project.