Silicon carbide: coming soon to a chip near you
Japanese crystal magic
New Japanese research into silicon carbide growth could revolutionise the electronics industry. A team of scientists has developed a method of making near-perfect silicon carbide crystals.
Silicon carbide has long been touted as a replacement for pure silicon in electronics. The crystal carries current much more efficiently than pure silicon, and is more robust: it can operate at much higher temperatures or under intense radiation. It can also withstand higher voltages.
But until now, attempts to manufacture flawless crystals large enough to use in electronics have failed
This breakthrough could pave the way for far more efficient electronic devices, and for devices that would operate in conditions too harsh for pure silicon: in fuel regulators inside jet engines, for example, or out in space.
The traditional growing process introduces defects - tunnels running through the crystals - that make them useless in electronics applications, according to Nature.com. Around 50 per cent of the crystals have these flaws - making production far too expensive to be a viable commercial proposition.
The team at Toyota Central Research and Development Laboratories in Nagakute, led by Kazumasa Takatori, have found a way to practically eliminate the flaws. Using their method they can grow crystals up to seven cm across with fewer than one percent of the flaws in conventionally produced crystals. The team has accomplished this by growing their crystals in stages.
They direct the growth of the crystal so that at the start of each stage, growth - by vapour deposition - is allowed only on the cleanest crystal surface.
Takatori says that silicon carbide is "one of the most excellent materials for high-power electronic devices". He and his team are working to refine the production process and are confident that they will be able to commercialise the technology. ®