Smartphones, which have become an indispensable presence in our daily lives, are luring the attention of consumers with their constant upgrades in display resolution. This is largely attributable to the size of image pixels which continue to get smaller and smaller. On a more microscopic level, this is driven by new materials that deliver greater performance while enabling more compact form factors. As such, smartphone performance is being maximized as devices are developed with oxide semiconductors that contain novel properties in place of conventional silicon materials.

The Oxide & Quantum Materials Laboratory led by professor Son, Junwoo at the Department of Materials Science & Engineering, POSTECH, is committed to the research of oxide semiconductors created through metal-oxide combinations. The periodic table places metals on the left and oxygen on the right: when metals mix with oxygen, highly robust oxides with ionic bonds are formed. This process also accompanies the generation of novel properties that conventional silicon semiconductors with covalent bonds are barely able to deliver. These properties can be applied across many devices to develop next-generation semiconductors or low-energy-consuming devices capable of demonstrating breakthrough performance.

The Lab generally focuses on three types of oxide materials. First, researchers work with oxides that mix with tin metals; these oxides are transparent and enable electrons to move rapidly, which makes them the ideal material for high-resolution displays, image sensors and high speed electronic devices. Second, they focus on titanium-based oxides that exhibit a spontaneous polarization and thus create ferroelectricity which is required to develop non-volatile memory devices. Last but not least, they take great interest in vanadium-based oxides that switch from insulator to conductor within an extremely short timeframe, rendering them appropriate for high-performance switching devices or ultra-sensitive sensors.

The vacuum equipment established by the Lab allows researchers to stack extremely thin oxide layers at the atomic level and observe them in real time through high-energy electron beam. This process can be compared to the stacking up of Lego blocks: a variety of oxide materials are built up to the thickness and number of layers defined by their design. It is at the nanometer level that materials are synthesized and desired properties are maximized to help conduct basic research on novel materials and consequently develop high-performance materials. These findings have been published in such internationally-acclaimed journals as the ‘Nature Materials’ and ‘Nature Communications’.

The Oxide & Quantum Materials Lab is building on these research achievements to perform joint research with Samsung Electronics, LG Electronics, Samsung Electro-mechanics and other Korean businesses. As the Lab was chosen by the National Research Foundation of Korea to undertake its collaborative Basic Research Lab (BRL) grant and create a strong basic research foundation in so doing, the Lab now aims to fulfill its role helping to resolve the challenges posed to the nation’s materials and components industry. Researchers at the Lab are working together in line with the shared philosophy that ‘it is new materials that have a critical impact on the properties of devices’, with a goal of bringing a dramatic improvement in device performance by focusing on materials rather than on the devices themselves.