| 학회 | 한국재료학회 |
| 학술대회 | 2018년 봄 (05/16 ~ 05/18, 삼척 쏠비치 호텔&리조트) |
| 권호 | 24권 1호 |
| 발표분야 | 1. 마이크로 LED 제작 및 응용기술(Micro LEDs: fabrication and applications)-오거나이저: 이인환 교수(고려대) |
| 제목 | Stretchable micro-LED display based on transfer printing method |
| 초록 | Highly deformable, stretchable displays have been intensively investigated for their new potential applications such as smart clothing and electronic healthcare monitor. Stretchable polymeric or organic light-emitting diode (OLED) displays based on elastic composite electrodes, comprising silver wires or carbon nanotubes, and stretchable electroluminescent displays based on conductive hydrogel have been demonstrated. These approaches exhibit attractive and inspiring features, but they have important drawbacks such as demanding special encapsulation, complicated fabrication processes, extremely difficult alignment for large area, and high-resolution pixels. Alternative approach is the use of micro-sized inorganic LED, which is more robust, longerlived, and compatible with conventional fabrication processes. Recent work has shown the fabrication of micro-LEDs on a stretchable rubber. However, the display was passive matrix type, which sequentially addresses each pixel in a row–column scheme with a high rastering frequency, requires high power consumption (to overcome the ohmic losses), and high resolution (which limits the display size). These limitations restrict the application range of PM displays. Here, we integrated a stretchable, active matrix (AM)-type inorganic LED display driven by thin film transistors (TFTs) fabricated from single crystal Si, which would achieve large-size displays with rapid response time and low power consumption. The micro-LEDs and Si-TFTs were moved from source wafers to a rubber substrate by triple successive transfers with a soft roller stamp and high overlay alignment. To improve the electromechanical stretchability, the LEDs and TFTs were interconnected with each other using serpentineshaped metallic thin films. The roll-based transfer enables integration of heterogeneous thin film devices on a rubber substrate with preserving excellent electrical and optical properties of those devices, comparable to their bulk properties. The electron mobility of the integrated Si-TFTs is over 700cm2/Vs, and this is attributed to the good interface between the Si channel and the thermally grown SiO2 insulator. The light emission properties of the LED are of wafer quality. The resulting display stably operates under tensile strains up to 40%, over 200 cycles, demonstrating the potential of stretchable displays based on inorganic materials. |
| 저자 | 안종현 |
| 소속 | 연세대 |
| 키워드 | micro-LED; stretchable display; active matrix |
