Blogs, Rooftop, Solar

The Solar Technology Behind Apple’s iPhone 6

Apple is expected to unveil a new iPhone 6 this week with a thin sapphire screen that is incredibly scratch resistant.

And the company can thank the solar industry for that innovation.

The super-thin screen is made through a process called proton induced exfoliation or PIE invented by Twin Creeks Technologies. With PIE, high-energy protons are fired at a crystalline material like sapphire or silicon and lodge in the material at a depth of around 20 microns. When heated, the ions form bubbles which ultimately link together and cleave off a thin crystalline slab that can be used as a screen or as a substrate for LEDs or solar cells. Hyperion, Twin Creeks’ first system for harnessing PIE, was in development for several years and debuted in 2012.

You could almost think of it as an atomic-level meat slicer.

The advantages of PIE are fairly significant as James Montgomery described in 2012:

That impressive reduction in silicon usage has a cascading effect on reducing costs all along the solar PV manufacturing process, from other steps that can be dialed back or even eliminated (forming, shaping, resizing and texturing silicon) to reduction in other materials used (e.g. less silver paste). And getting wafer thinness down to around 20 microns has another benefit: the monocrystalline wafer is actually flexible, so all it needs is a good laminate to make modules, without all the rigid glass and EVA encapsulants or other expensive backings. All that adds up to eliminating as much as 50 percent of a cell/module makers’ capital spending costs (“capex”), or several dozen pieces of equipment, in a typical 100-MW solar manufacturing line. (That doesn’t include possible savings on the balance-of-systems side too. For example, new racking and wiring schemes that don’t have to deal with heavy glass-sandwiched modules.)

“We can make less than $0.40/W cells today,” CEO Siva Sivaram says, with $0.20/W for silicon and just $0.20/W for processing. Today’s rooftop solar PV panels take two years to pay back the power used to create them, he points out; “we can do it in 25 days.”

Ion implantation procedures had been studied for years, but had yet to live up to their full commercial potential. Hyperion was poised to be the breakthrough commercial system. The company employed some of the leading scientists in the field and they had been perfecting the technology for decades. The company also had a demo facility in Mississippi and a seasoned management team lead by Sivaram. (Disclosure: I was the outside marketing consultant. It was one of the most fun projects I ever worked on.)

So what happened? The timing was incredibly unfortunate. Hyperion debuted at the same time of a dramatic consolidation in the solar industry. Solar companies were closing factories and had very little interest in investing in new equipment. Capital equipment is one of the most challenging markets in the world. Customers will test equipment for months, if not years, before investing. A downturn in the market even makes it worse.

GT Advanced Technologies bought the assets for around $10 million later in the year. The Apple screens will be coming out of a plant in Arizona.

If Twin Creeks came out with Hyperion two years earlier or two years later, the story may have been different.

Using the system for cell phone screens in many ways makes more sense than solar. High-end cell phones are luxury items. Cost matters less if you can give consumers they’ve never had before. Solar is utilitarian: it’s all about dollars and cents. Cell phone screens are also passive.

Still, if the screens succeed with Apple, it may provide a foundation to expand Hyperion and bring it back to solar.