광소결 방법을 이용하여 소결된 탄소나노튜브/구리 나노입자 잉크 패턴의 피로특성 향상에 관한 연구

Abstract

For the flexible electronics, the sintered metallic nanoparticles (NPs) film is necessary to be durable in severe conditions such as bending, twisting, and stretching. In this work, the effect of carbon nanotube (CNT) in Cu NPs ink was investigated for increasing the fatigue property of CNT/Cu NPs ink patterns under repeatable bending condition. The CNT/Cu NPs ink was fabricated, and then the fabricated ink was printed on the flexible polyimide (PI) substrates by using a doctor blading method. For the sintering method, a flash light sintering process was used to sinter the CNT/Cu NPs ink patterns in few milliseconds with room temperature and ambient condition. The fatigue characteristics of the flash light sintered CNT/Cu NPs ink patterns were estimated using the outer bending fatigue tests with three different bending radius (7 mm, 10 mm, and 15 mm). It was a noteworthy that the flash light sintered CNT/Cu NPs ink pattern showed higher mechanical durability after 103 cycles than Cu NP ink pattern by adding only 1 wt% of CNT (The resistance change (ΔR/R0) of the Cu NW/NP film was 6.02 while that of the Cu NP film was 84.03 at 103 cycles under the 7 mm of the bending fatigue radius). Furthermore, the sheet resistance of flash light sintered CNT/Cu NPs ink pattern decreased than that of Cu NPs ink pattern (The sheet resistance of the Cu NPs ink pattern: 128.01 μΩ·cm, CNT/Cu NPs ink pattern: 110.49 μΩ·cm). Therefore, it is expected that CNT/Cu NPs ink will be used in the future in flexible electronics applications.