By Michael Fisher | April 3, 2013 6:46 PM
If you followed our coverage from MWC in Barcelona, you might remember a demo by Jeff Nestel-Patt of GT Advanced Technologies, showcasing a smartphone display 2.5 times stronger than Gorilla Glass that was, for all intents and purposes, impervious to scratches. If you missed that video, maybe you caught our article from last week discussing sapphire’s importance to the future of the mobile industry. If you missed both of those, then you’re still in luck – because this piece right here trumps them both.
You see, it turns out that the GT Crystal Systems facility at which much of the aforementioned sapphire is manufactured sits just up the road from Pocketnow’s Boston offices in Salem, MA. So Jeff, being the nice guy that he is, invited us for a visit to get a feel for just how sapphire smartphone displays are made. And since we like science and smartphones, and really like it when those two fields intersect in a way we can photograph, we packed our camera and went for a ride.
An important thing to note is that GT Crystal Systems isn’t as focused on producing sapphire displays as it is on selling the technology that enables other companies to do it. The core of that technology is the company’s special furnaces: there are about 60 at the Salem facility, each of them a 2100-degree chamber of hot, hot innovation.
The process is relatively straightforward: a sapphire seed, about the size and shape of a hockey puck, is placed at the bottom of a single-use molybdenum barrel called a crucible. The crucible is then filled with a mixture of condensed corundum -a crystalline form of aluminum oxide- and a material called “crackle,” sapphire material left over from previous runs. The full crucible is then placed inside the furnace, where it sits atop the “finger,” a small liquid helium-cooled platform that prevents the sapphire seed from melting too early. The furnace is sealed, the air is evacuated, and the temperature is brought up to 2100 degrees Celsius to allow the materials to melt together. (The video says 2200, but that’s wrong. It’s 2100, for all you making-sapphire-at-home hobbyists.) The material is put through a series of cooling cycles over the next 16 or 17 days, during which time the sapphire slowly crystallizes from bottom to top. The end result is this: a 115kg cylindrical section of industrial sapphire called a “boule.”
Making a smartphone display out of this material is also pretty simple. A rectangular section of specific dimensions is cut, polished, and sliced to the appropriate thickness. A few hole punches later, voila: you’ve got a thin, light screen protector harder than Gorilla Glass – tougher, even, than almost any material except for diamonds: a practically un-scratchable display coating.
Accessory applications like that are already in the works from other companies, but GT Advanced is also hoping to coordinate with OEMs to include sapphire screens on smartphones right out of the box. Cost remains a big factor, but the gap is narrowing rapidly. Whereas several months ago, sapphire displays cost about $30 per smartphone, the company told us that current figures are more like $15, with next-generation technology coming in the next 12-18 months to bring that figure down further – to less than ten bucks a screen. It’s not the $3 per display that Gorilla Glass is said to cost, but it’s definitely much closer.
You’ll see other companies pushing sapphire smartphone screens much more aggressively under their own brands at first, but get ready for a general sapphire awareness campaign coming soon. GT Advanced is committed not just to creating more sapphire material, but creating more capacity for other companies to produce it, by selling its furnaces to them. That should drive the costs down while pushing availability up – which means that sooner rather than later, we might all be able to carry our smartphone in the same pocket as our keys, coin change, and even a handful of beach sand, without worrying about scratching our screen to death. That’s a future we can all get behind.
While you ponder the possibilities, make sure to check out our video tour of GT Crystal Systems, and leave a comment with your thoughts on the future of scratch-proof displays down below.