A Look at How GT Advanced Makes Sapphire Glass for Smartphone Displays

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Original poster
Apr 12, 2001
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Yesterday, the State of Arizona and GT Advanced announced that Apple is building a new 700-employee factory in Arizona to make sapphire glass. Apple will contract with GT Advanced, with that company owning and operating furnaces and related equipment at the facility.

Back in April, Pocketnow went to GT Advanced's factory in Massachusetts to find out how sapphire displays are made. It's likely that the facility in Arizona will use a similar process, though we do not yet know what Apple will use the sapphire for. A safe bet would be the company's rumored smart watch product -- many luxury watches use sapphire glass because of its durability.

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."
The new factory is expected to use next generation, large capacity furnaces with an emphasis on lower cost, higher volume sapphire glass manufacturing.

Apple currently uses small pieces of sapphire glass -- which provides superior durability and scratch resistance to other forms of glass -- to protect the cameras on the iPhone and on the home button for the new Touch ID-equipped iPhone 5s. A report from earlier this year suggested that future smartphones may use sapphire, a crystalline form of aluminum oxide, instead of more traditional forms of glass.

Article Link: A Look at How GT Advanced Makes Sapphire Glass for Smartphone Displays
 

Clubber

macrumors member
May 29, 2009
92
7
I don't think I've ever scratched my iPhone screens. I've dropped and shattered them but never scratched. Am I just lucky?
 

hiptobesquare

macrumors regular
Apr 20, 2003
177
8
Iowa
Sapphire glass is crystalline Aluminum Oxide...

I suppose it is fitting that Apple is getting into the transparent aluminum oxide crystal manufacturing business, considering that Scotty gave a 20th century engineer the formula for transparent aluminum, using a Mac Plus.



"Computer. Hello, Computer..."

"The keyboard... how quaint."

Quaint indeed now, with on-screen keyboards, and voice recognition and response. Scotty could actually converse with a Mac with dictation and voice commands, and iPhone's Siri. Majel Barret should have been the voice for Siri and Apple's Speech response. (Better than Siri or Vicki.)

Just imagine what another 30 years will do for technology... considering the last 30 years between the original 1984 Macintosh, and the ready-for-2014 iPad Air and next month's Mac Pro.
 
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macduke

macrumors G4
Jun 27, 2007
10,956
14,646
Central U.S.
I've had small scratches on a couple of my iPhones—one that was slightly annoying on my iPhone 5 before I swapped it out to have the sleep/wake button fixed. Overall though I think more people have problems with breaking the screen than scratches. I want to know if Sapphire makes it more shatter resistant? If I remember right from my Geology class and lab in college, crystalline structure makes it harder but not necessarily stronger? I think it's pretty easy to smash diamonds.

This would be great for the iPad if it does make it stronger too. Everyone on my team at work has a cracked iPad screen lol. Well not my boss anymore but she just got hers swapped recently. Though she did drop it again and dented the corner and slightly chipped the edge of the glass. And they even use cases. I can't figure it out. I only had a smart cover until selling my iPad 2 (waiting for the Mini Retina to ship).
 

Konrad9

macrumors 6502a
Feb 23, 2012
560
38
Sapphire glass is crystalline Aluminum Oxide...

I suppose it is fitting that Apple is getting into the transparent aluminum oxide crystal manufacturing business, considering that Scotty gave a 20th century engineer the formula for transparent aluminum, using a Mac Plus.

Image

"Computer. Hello, Computer..."

"The keyboard... how quaint."

Quaint indeed now, with on-screen keyboards, and voice recognition and response. Scotty could actually converse with a Mac with dictation and voice commands, and iPhone's Siri. Majel Barret should have been the voice for Siri and Apple's Speech response. Better than Siri or Vicki.)
She died in 2008 :\
 

BC2009

macrumors 68000
Jul 1, 2009
1,949
260
I don't think I've ever scratched my iPhone screens. I've dropped and shattered them but never scratched. Am I just lucky?
Yes , you are lucky. It usually takes me about 16 to 18 months before I get a noticeable scratch, but it is certainly possible. Most easily on the iPhone 4/4S with a slider case and getting a grain of sand caught in there and having it scratch the back. But I've even gotten micro scratches on the front. You can't see them in normal use, but if you turn off the display and hold the phone at angle they become visible. These invariably come from forgetting that my keys are in my left pocket and sliding my iPhone in there or from dropping the phone.

Since I got the iPhone 5s, I have been double checking my pockets before putting my iPhone 5s in them to make sure I have nothing that can scratch it. I don't like cases on my iPhone and the one time I used one (a slider case for iPhone 4s), the case was the thing that actually caused the scratch on the back glass.

Getting sapphire displays on iPhones would be a huge deal for those of us who hate using cases on our iPhones.
 

hiptobesquare

macrumors regular
Apr 20, 2003
177
8
Iowa
She died in 2008 :\
I know, but one would think there are enough voice samples from Star Trek and other recordings, to create a reasonable digital facsimile of her voice-print, for her to live on in the culture, as the voice of actual computers, as well as the voice of fictional star trek computers.

RIP Majel Barrett, Gene Roddenberry, DeForest Kelley, and James Doohan.
 

WaxedJacket

macrumors 6502a
Oct 18, 2013
582
818
Gorilla glass user and never had an issue with screen scratches. I constantly drop my phone too :eek:
 

paulsdenton

macrumors 6502
Oct 9, 2010
474
38
Barton, Vermont USA
Amazing stuff

Apple can't go wrong getting into the use of sapphire. It is an incredibly versatile product. For one thing it is awesomely hard, far harder than Gorilla Glass. I've never had a problem with Gorilla Glass but it is used by everyone and using a superior ingredient is consistent with Apple quality. Helps differentiate the Apple brand as superior (yet again).

It transmits light across the entire spectrum with no distortion. That's why it is used in the scanners at checkout counters; almost no read errors.

Less known is it's non-optical possibility, as substrate for chip manufacture. It has a low conductivity rate for electric current but a high transmission rate for heat. This obviously would allow it to conduct heat away from high capacity processors.

IMHO this is one of the materials that will find greater and greater use in the types of products that Apple now builds and may build in the future. maybe a transparent iPhone in our future!
 

Bowsa2511

macrumors regular
Oct 21, 2013
117
0
This is pretty fascinating, I didn't even know they could make them artificially! Here I thought they had to mine sapphires and then press them into screens
 

sishaw

macrumors 65816
Jan 12, 2005
1,147
19
Sapphire glass

Sapphire glass is very scratch resistant, but, as I know from my watch, it can chip, especially at the edge. I guess anything can get damaged given enough, or the right kind of, stress. At any rate, I'm curious as to whether this is for the phone screen, or as some have suggested, the camera lens or the iWatch (if it ever goes to market).


(kidding) Or maybe the 60-inch Apple TV?? (/kidding).
 

doug in albq

Suspended
Oct 12, 2007
1,449
244
This glass plant can only be for the windows of the upcoming Apple "spaceship" campus, nothing else makes any sense. :rolleyes:
 

bloggerblog

macrumors member
Jun 27, 2007
97
0
Harder material are more susceptible to cracking than soft.
I.e. Glass is more likely to crack when struck than say iron or plastic.
 

FirstNTenderbit

macrumors 6502
Jan 15, 2013
355
0
Atlanta
Apple can't go wrong getting into the use of sapphire. It is an incredibly versatile product. For one thing it is awesomely hard, far harder than Gorilla Glass. I've never had a problem with Gorilla Glass but it is used by everyone and using a superior ingredient is consistent with Apple quality. Helps differentiate the Apple brand as superior (yet again).

It transmits light across the entire spectrum with no distortion. That's why it is used in the scanners at checkout counters; almost no read errors.

Less known is it's non-optical possibility, as substrate for chip manufacture. It has a low conductivity rate for electric current but a high transmission rate for heat. This obviously would allow it to conduct heat away from high capacity processors.


IMHO this is one of the materials that will find greater and greater use in the types of products that Apple now builds and may build in the future. maybe a transparent iPhone in our future!
Used in an iWatch or something small where the sapphire can be thicker, it might be viable. As a display it would be fairly cost prohibitive. It's what, 3-4x more expensive than GGlass? Also I think cracking is a larger issue than scratches on mobile devices. <- just my opinion. That's where sapphire's hardness can be a detriment.

One thing I personally wouldn't want. A sapphire display that made the device price raise substantially.

Bolded: wanted to give wikipedia a hat tip for your info.;)
 

Xenomorph

macrumors 65816
Aug 6, 2008
1,311
556
St. Louis
Anti-glare screen protectors improve the display quality (no glare) and protect against scratches.

The problem then is how easily glass shatters. There isn't much that can be done to protect against that.

Using sapphire means the device will become MORE susceptible to cracking or shattering.
 

mrfoof82

macrumors 6502a
May 26, 2010
574
13
Lawton, OK
Sapphire glass is tougher than Gorilla Glass, but it's also heavier.

Sapphire glass has a density of 3.98g/cm3, whereas Gorilla Glass has a density of 2.45g/cm3. Sapphire is 60% heavier. This might be able to be offset by using a thinner piece of sapphire, which would also improve the perceived quality of the display since the display is separated by less material.

If Apple does move to sapphire, on account of both weight (which needs to be compensated for elsewhere) and material cost, I'd expect it to be used only in higher-end devices.
 

Doc C

macrumors regular
Nov 5, 2013
204
131
Crystalline Structure is the issue...

From what I understand (admittedly, too little, so feel free to correct me), the issue with most metals is the crystalline structure. Apple bought into LiquidMetal Inc, via some convoluted contract and shell corporation and such. My understanding of the concept behind Liquid Metal is that they found a way to disrupt the crystalline structure of the metals so that strength as well as numerous other physical properties are improved - best to see the company website for full details as this isn't my area of expertise:

Liquid Metal Technologies

I wonder if Apple is working on, planning, or somehow thinking about a way of "doping" the crystalline structure of the sapphire in order to do a similar thing - that is, to minimize the tendency to shear while maintaining the durability and clarity.

Just a thought...


PS - I have no affiliation with the above company
 

staveb

macrumors member
May 13, 2009
55
0
Great presentation. I can't wait to have an iPhone screen made out of that stuff. Make sure to sell your shares in Zagg before this comes out for iPhone. :)

Why was the audio really bad at the beginning and the end, with a hauling wind muffling the audio? They shouldn't have released something with such poor audio buffering the piece in the front and back ends.
 

MVallee

macrumors 6502a
Feb 8, 2007
807
182
Ontario, Canada
Never had a scratch on any of my iPhone screens and haven't used screen protectors. Still any technology to help prevent scratches sounds good to me.
 

paulsdenton

macrumors 6502
Oct 9, 2010
474
38
Barton, Vermont USA
Used in an iWatch or something small where the sapphire can be thicker, it might be viable. As a display it would be fairly cost prohibitive. It's what, 3-4x more expensive than GGlass? Also I think cracking is a larger issue than scratches on mobile devices. <- just my opinion. That's where sapphire's hardness can be a detriment.

One thing I personally wouldn't want. A sapphire display that made the device price raise substantially.

Bolded: wanted to give wikipedia a hat tip for your info.;)
The hardness cuts both ways; this material is also used in armored vehicle windows.

I was first introduced to this amazing material some years ago when Cyrus Gregg showed me around the Saphikon plant in Milford, NH. At the time the Gregg family (Governor Hugh, US Senator Judd and Colonel William, who was deputy commander at the 1777 Battle of Bennington) owned Saphikon, it has since been acquired by St Gobain. The process was different then, they extruded the stuff in long ribbons in towers rather than in boules, as they do now. The process uses vast amounts of electric power, which is the reason it is so expensive.

Nevertheless, the cost keeps coming down as the utilization increases. It may never be as low in cost as any kind of glass, but it is a very superior product. I would pay a premium for it, but Apple would probably just build the cost in and offset it with savings or reduced margin. I really think we will see a lot more of this material in displays going forward.
 

richeyty

macrumors member
Jul 25, 2013
72
4
If this isnt a screaming alert in apples face, apple is doomed. This is exactly what they need.
 
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