Yesterday, New Hampshire-based materials manufacturing company GT Advanced announced a multi-year agreement with Apple to provide steady supply of the sapphire glass, a crystalline form of aluminum oxide known for its superior durability and scratch resistance. Apple relies on this pricey gemstone to protect the iPhone 5s’s Touch ID sensor and has been using it for camera lens cover on all iOS devices since the iPhone 5.
The strategic supply agreement is valued at more than half a billion dollars in cutting-edge equipment and some folks have combed through Apple’s patent filings for a clue to building next-generation iDevices with sapphire glass covers instead of Gorilla Glass.
Here’s a video tour of GT’s manufacturing process behind making the scratch-resistant, tougher-than-Gorilla-Glass sapphire displays for smartphones…
The video was recorded by Pocketnow, which toured GT’s Massachusetts factory six months ago and was given a unique peek behind the curtain by Jeff Nestel-Patt of GT Advanced Technologies.
The process is relatively straightforward, the publication wrote back in April:
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.”
A sapphire-made smartphone display cover is 2.5 times stronger than Gorilla Glass and tougher “than almost any material except for diamonds,” leading the author to describe it as “a practically un-scratchable display coating”.
Here’s the clip.
The GT Crystal Systems facility shown in the clip is located in Salem, Massachusetts, but GT has acknowledged in yesterday’s media release that it will “produce the material at an Apple facility in Mesa, Arizona”.
GT says it’s accelerated the development of a next generation, large capacity ASF furnaces (see the image top of post) to deliver “low cost, high volume manufacturing of sapphire material”.
The State of Arizona yesterday confirmed Apple is building a new 700-employee Arizona plant, which an Apple spokesperson confirmed will “make components for Apple products” and run on 100 percent renewable energy “from day one”.
The terms of the agreement include a $578 million Apple pre-payment to GT for the “furnaces and related equipment” to be used at the upcoming Mesa facility. GT will then reimburse the iPhone maker over five years, starting in 2015, so Tim Cook & Co. are basically buying these advanced furnaces in advance.
Similarly, Apple prepays billions to Foxconn for the manufacturing equipment and then bills CEO Terry Gou, which is basically a form of long-term reimbursement. Interestingly enough, Apple recently filed for a patent on a new kind of a sapphire lamination process which results in a protective coating that’s just 1mm thick.
The patent application titled ‘Sapphire Laminates’ suggests Apple has developed manufacturing processes to make the expensive gemstone a viable option for the mass production of consumer electronics devices, describing the lamination of sapphire sheets, as well as sapphire-on-sapphire or sapphire-on-glass applications.
Specifically, Apple mentions using two 0.55mm sheets, one to protect against a screen getting scratched and the other against screen breakage.
Some industry watchers speculate the Apple-GT relationship has a lot to do with the rumored iWatch project.
Billed as the industry’s lowest cost sapphire producer, GT Advanced aims to sell smartphone sapphire covers for less than ten bucks a screen versus the industry-standard $30 per-display going rate back in April 2013.
By comparison, Gorilla Glass is $3 per display.