Er is een revolutie op komst in hoe processoren gaan werken. De oude manier bereikt langzaam maar zeer zeker zijn plafond en de limiterende factor is hitte. Om dit te overkomen zou de productie van processoren weg van koper moeten gaan en als beter alternatief photonics gebruiken.
Voordeel hiervan is dat photonics geen weerstand kennen en dat is a) sneller en b) geen hitte en c) minder stroom. De Holy Grail voor processoren dus.
En dat is onderzoekers nu gelukt, en wel in Einhoven. Hup Holland.
Hexagonal structure
“The crux is in the nature of the so-called band gap of a semiconductor,” says lead researcher Erik Bakkers from TU/e. “If an electron ‘drops’ from the conduction band to the valence band, a semiconductor emits a photon: light.” But if the conduction band and valence band are displaced with respect to each other, which is called an indirect band gap, no photons can be emitted - as is the case in silicon. “A 50-year old theory showed however that silicon, alloyed with germanium, shaped in a hexagonal structure does have a direct band gap, and therefore potentially could emit light,” says Bakkers.
Shaping silicon in a hexagonal structure, however, is not easy. As Bakkers and his team master the technique of growing nanowires, they were able to create hexagonal silicon in 2015. They realized pure hexagonal silicon by first growing nanowires made from another material, with a hexagonal crystal structure. Then they grew a silicon-germanium shell on this template. Elham Fadaly, shared first author of the Nature paper: “We were able to do this such that the silicon atoms are built on the hexagonal template, and by this forced the silicon atoms to grow in the hexagonal structure.”
Het is uiteraard een heel verhaal, je kan het nalezen op Nature.com of hier: https://www.tue.nl/en/news/news-overview/08-04-2020-eindhoven-researchers-present-revolutionary-light-emitting-silicon/