Groundbreaking Polymer Insulating Layers Bring the Era of IoT Closer
“Thus far, thin insulating layers for electronic devices have used inorganic materials such as oxides. However, these substances have limited flexibility and, therefore, were difficult to apply to flexible electronic devices. In order to bring the Internet of Things (IoT) technologies closer to people’s everyday lives, it is foremost necessary to use wearable and flexible electronic devices. Considering the low capacity of batteries used for wearable devices, it is also essential to develop low-power electronic devices. The ultrathin polymer insulating layers developed in the recent research concurrently provide the mechanical flexibility and outstanding insulation that wearable electronic devices are looking for. Once this material is used for producing low-power flexible electronic devices and for a wider range of futuristic electronic appliances, the era of the IoT will be brought forward at a faster pace.”
Application for Futuristic Wearable and Flexible Electronic Devices Accelerates the Arrival of Dream Devices
As a substitute for solid, heavy material based on inorganic materials, low-power polymer insulating layers were developed for the use for futuristic wearable and flexible electronic devices, signaling the arrival of the era of the Internet of Things (IoT).
In collaboration with Profs. Im, Sung Gap and Cho, Byung Jin, Prof. Yoo, Seunghyup’s group at KINC successfully developed polymer insulating layers that can be down-scaled below 10nm, equivalent to 1/10,000 of a human hair. Published in Nature Materials, a sister journal of the world-famous scientific journal Nature, the developed polymer insulating layers exhibit insulating properties ideal for low-power soft electronic devices. This ultrathin layer prevents electric currents from flowing even when a strong electric field exists. Having participated in the joint research, Prof. Im, Sung Gap compares the developed polymer withstanding such a high field with a very thin plastic vinyl layer holding a huge amount of water without any leakage. The polymer layer can actually resist an extremely strong electric field, equivalent to millions of volts for one-centimeter thickness.
Ultrathin insulating layers are critical elements that enable the operation of transistors, a core unit device constituting most functional integrated circuits today. In general, transistors are comprised of three electrodes, a semiconductor, and an insulator. Among the three electrodes, one called a “gate electrode” plays the role of a knob in a faucet, switching on or off the electric current flowing through the semiconductor. The gate electrode works in such a way because the insulating layer existing between the gate electrode and semiconductor can change the latter’s conductivity. In particular, when the insulating layers become thinner, the semiconductor has stronger conductivity at the same gate voltage, ultimately making it possible to develop low-power devices.
For existing transistor devices, ceramic substances such as oxides have been used to produce high-quality ultrathin insulators. However, ceramic materials are highly susceptible to bending-induced cracks, which makes them inadequate for flexible devices. Against this backdrop, the joint research team turned to the initiated chemical vapor deposition (iCVD) and developed high-quality 10-nm-level polymer insulating layers that can operate transistors at a low voltage. Although the wearable devices available today mostly take the form of smart watches, the ultrathin layers are expected to help develop easily expandable or bendable futuristic electronic devices in the form of patches that attach to human skin, for example. Such devices will enable comprehensive, ongoing monitoring in the medical and healthcare sectors without resorting to heavy or bulky equipment. In addition, displays that can be bent or folded without compromising their outstanding performance are expected to bring a revolutionary transformation to the future display market.
Once technologies are further developed for the customized design of insulating layers for different uses, coupled with realization of creative devices to take advantage of the unique properties of those layers, the ultrathin insulating layers are expected to significantly contribute to the development of low-power flexible electronic devices.
Prof. Yoo, Seunghyup 2015 Annual Report