The creators of organic light-emitting diode (OLED) displays are working hard to develop bigger, more flexible and completely transparent versions of the screens now found on the tiny screens of mobile phones. I'll grant them the bigger would be good, and there are probably good reasons for flexible - but I just can't quite understand the attraction of transparent. I mean, I really don't want anything digital interfacing with my eyeglasses and obstructing my view.
But then again, I'm the worst video game player ever. So maybe I'm not the target market here.
To date, the main problem with developing these roll-up, transparent screens isn't the screen so much as the transistors controlling the screen pixels. The current transistors - polycrystalline silicon - are just too, well, visible.
Researchers have a solution - in fact, they have three solutions. The question, according to this article from Technology Review, is which technique for creating see-through transistors will emerge as the standard.
Technology Review reports the three competing methods are:
- Use zinc-oxide and indium-oxide nanowires. This is the most recent break-through, developed by researchers at Purdue and Northwestern universities. This method actually creates smaller and better transistors than existing transistors. But, there's no way to control what happens when you dump the nanowires on a surface. So, cross your finger and hope one out of a thousand line up the way it needs to. Obviously, this doesn't bode well for mass manufacturing.
- Use thin films of zinc-oxide or indium oxide. Easy to fabricate, but with lower mobility.
- Use carbon nanotubes. These transistors are stronger than new nanowire transistors and have better electron mobility, but since they require a metal contact for connecting nanotubes to the electrodes, they aren't completely transparent.
At this point, it's a race to the standard. Transparency, electrical performance and flexibility, and the cost of manufacturing will determine the ultimate winner, according to one professor of materials science and engineering interviewed in this article.
Forget the Preakness. This is the race to watch.