Glass thinner than a human hair is now strong and flexible enough to be used in a wide variety of high-tech applications. The technology group SCHOTT is one of the few companies in the world that develops and manufactures ultra-thin glass for cutting-edge features in smartphones of the future, including cover glasses, substrates for flexible OLED displays and wearables, camera systems, novel micro batteries, processors and fingerprint and bio-sensors.
By using innovative materials and its own proprietary down-draw technology, SCHOTT can reliably produce ultra-thin glass as thin as 25µm today. These glasses offer many advantages over other materials such as plastic or silicon, support the trend toward miniaturisation and make exciting concepts possible in the race to develop smartphone technologies of the future.
Hardened ultra-thin glass is scratch-resistant and bendable up to a radius of a few millimeters and doesn’t show any signs of fatigue. Furthermore, it has excellent barrier properties and protects against environmental influences. This makes it an ideal substrate or encapsulant for OLEDs that ultimately make bendable or foldable displays possible. This then opens the door for manufacturing flexible smartphones or so-called wearables, in other words devices that can be worn as bracelets or be integrated into textiles.
Capacitive fingerprint sensors are becoming increasingly important for secure identification of smartphone users. To achieve the highest recognition accuracy, they require covers that are as thin as possible that must also be very strong. Ultra-thin glass from SCHOTT has a uniquely high dielectric constant; therefore the sensor signal is attenuated only very slightly on the way to the finger. SCHOTT is currently the only company that manufactures chemically hardened ultra-thin glass that offers four times higher strength than unhardened base glass. Thanks to their high optical quality, such glasses can be used in smartphone cameras: as chemically hardened cover glass or IR-cut filters for CMOS image sensors.
Ultra-thin glass also withstands the increasing heat generation of high-performance processors in smartphones better than plastics that are currently being used in chip packaging. Even the thinnest glass does not bend during use and thus makes extremely flat device types possible. Ultra-thin glass also represents a promising alternative to silicon as a substrate material for penetrations and for distributing data streams between processors, memory chips and other components. The unique high-frequency electrical properties of glass allow for data to be transported with lower electrical losses and thus longer battery runtimes for smartphones.
Laser-engineered ultra-thin glass can increase current data transfer rates by a factor of up to eight and is thus the material of choice as a substrate for space-saving chip packaging. Micrometer-thin glass is also an ideal substrate for novel thin-film batteries and contributes directly to higher performance. These next gen micro-batteries supply electricity to even the smallest autonomous devices or sensors. Potential fields of application include, for example, wearables, small security cameras, but even more importantly, the IoT.
“Thanks to these exciting future trends in the electronics industry, our developments in the area of ultra-thin glass are meeting with ever greater interest. We are in close contact with development and industry partners and see relevant growth potential for SCHOTT,” says Dr. Ruediger Sprengard, Director of New Business for Ultra-Thin Glass at SCHOTT Advanced Optics.