Latest Innovation: New Printing Method Paves the Way for Flexible Electronics
Latest Innovation: New Printing Method Paves the Way for Flexible Electronics
A team of researchers from the Institute for Basic Science (IBS), South Korea, has introduced an innovative dry transfer printing technique for flexible electronic devices. Led by Prof. KIM Dae-Hyeong, Dr. LEE Sangkyu (IBS Center for Nanoparticle Research), and Prof. KIM Jihoon (Pusan University), this method enables the transfer of high-quality electronic materials without damage, representing a significant leap forward in the field of flexible electronics.
Traditionally, high-quality electronic materials require high temperatures for crystalline structure and electrical properties, posing challenges for direct processing on flexible substrates. Existing transfer printing methods often involve toxic chemicals and risk mechanical damage during the transfer process.
To address these limitations, the research team developed a novel dry transfer printing method that meticulously controls stress within thin films. This approach allows metal and oxide thin films, processed at high temperatures, to be seamlessly transferred to flexible substrates without compromising their integrity. By fine-tuning sputtering parameters, the team managed stress types and magnitudes within the thin film, creating bilayer structures with optimized stress gradients. Additional tensile stress through external bending deformation enhances the strain energy release rate, ensuring reliable delamination by surpassing interfacial strengths between the thin film and substrate.
Dr. SHIN Yoonsu, first co-author, highlighted, "Our transfer method avoids toxic substances, minimizes device damage, and eliminates the need for extensive post-processing, resulting in significantly reduced transfer times. It's capable of transferring large areas and intricate micro-scale patterns, making it highly adaptable."
Moreover, the team demonstrated that greater stress gradients within thin films lead to substantial bending moments, transforming them from two-dimensional (2D) thin films into complex three-dimensional (3D) structures. The configuration of these 3D structures can be customized by adjusting adhesive layer patterns during the printing process, facilitating the creation of tailored structures to meet diverse application requirements.
Dr. LEE Sangkyu, corresponding author, emphasized, "The core of our research lies in developing a damage-free dry transfer printing technique that solely controls material properties, unlike previous methods. Moving forward, we aim to explore the fabrication of diverse 3D devices, leveraging this technology beyond simple 2D flexible battery devices demonstrated in our study."
Prof. KIM Dae-Hyeong underscored the broad applications of transfer printing technology in flexible electronics, optoelectronics, bioelectronics, and energy devices, noting, "Our method offers substantial advantages for producing high-density 2D and 3D functional thin film structures without damage, thereby catalyzing the development of next-generation electronic devices."