Glass roll: Thin, flexible display glass can be spooled and used for roll-to-roll printing.
Corning’s flexible display glass is just 75 micrometers thick. VanDewoestine acknowledges that the concept of manufacturing durable electronics on flexible glass is counterintuitive. “People think manufacturing on flexible glass is impossible because they think about TVs getting broken by Wii remotes,” she says. The company is not saying how tough and strong the material is, but representatives say these properties should match those of thicker glass because the strength of glass is independent of its thickness.
Corning has sent out samples of the flexible glass to manufacturing partners to test on roll-to-roll manufacturing lines. VanDewoestine says the company’s partners are building electronic devices on the substrate; the company expects to reveal some of this work in scientific publications later this year, but is not currently disclosing any details.
Jennifer Lewis, professor of materials science and engineering at the University of Illinois at Urbana-Champaign, says she is excited about the potential for flexible glass. “This will enable a broader array of materials to be integrated into flexible electronics, and likely ones with better performance than could be achieved on plastic substrates,” she says.
But there is some skepticism about the compatibility of glass with roll-to-roll manufacturing. HP’s Taussig, who is developing roll-to-roll processes for plastic display backplanes, says: “Unfortunately, glass is brittle, so it is still susceptible to scratches, which can lead to cracks and catastrophic failure, which is the last thing you want in a roll-to-roll line.”
VanDewoestine says Corning is aware of such concerns and is addressing the problem by developing packaging that will protect the glass during transport and manufacturing. “The reason flexible glass works is that we make very pure glass with a damage-free surface, and then package it so that it remains defect-free,” she says. The packaging is similar in concept to the packaging the company uses to make glass optical fibers, which are about 125 micrometers wide and flexible.