| 학회 | 한국재료학회 |
| 학술대회 | 2018년 봄 (05/16 ~ 05/18, 삼척 쏠비치 호텔&리조트) |
| 권호 | 24권 1호 |
| 발표분야 | F. 광기능/디스플레이 재료 분과 |
| 제목 | Monolithic Flexible Vertical GaN MicroLEDs for Transparent Biomedical Stimulator |
| 초록 | In the upcoming internet of things (IoT) era, visual IoT platforms have attracted significant attention which can be used to visual communication in hyperconnected society. Flexible inorganic microLEDs have been considered as a key technology in visual communication, because of their excellent electrical/optical properties, long lifetime, fast response time and high stability in severe environments. Despite of several previous researches about flexible microLEDs, GaN flexible vertical microLEDs (f-VLEDs) on plastics have not yet been realized, due to the difficulty of GaN vertical interconnection. In this report, We demonstrate a high-performance flexible GaN f-VLED array through a simple LED fabrication process. XeCl excimer laser separated GaN LED chips from the transparent sapphire substrates. The freestanding microLED chips were isolated by biocompatible polymer layers, and vertically interconnected by using silver nanowires. Flexible transparent GaN VLED device was conformally affixed to a human fingernail with high irradiance of 30 mWmm-2. The lifetime of f-VLEDs was experimentally measured by the high accelerated stress test (HAST) and theoretically expected by the finite element analysis (FEA) simulation. Furthermore, the periodic bending/unbending test was used to investigate excellent mechanical durability of f-VLEDs. The wireless power supply system on human skin has been successfully transferred electrical energy to the f-VLED. Finally, the monolithic GaN f-VLEDs successfully emitted blue light onto a living mouse brain without severe histological damage in brain. |
| 저자 | Han Eol Lee1, Sang Hyun Park2, Jung Ho Shin1, Jung Hwan Park2, Jae Hee Lee1, Keon Jae Lee2 |
| 소속 | 1Department of Materials Science and Engineering, 2KAIST |
| 키워드 | <P>Light-emitting diode; Flexible GaN vertical LED; Wireless power transfer; Transparent MicroLEDs; Bioelectronics</P> |
