The fabricating study of organic optoelectronic devices by using ink-jet printing technology

• Main Authors: Guan-Cheng Wong, 翁冠晟
• Other Authors: Chin-Hsiang Chen
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/b6jrjq

碩士 === 正修科技大學 === 電子工程研究所 === 106 === The inkjet printing technology, for large-scale use of piezoelectric jet technology and research, will be introduced in this study. There are several main technical advantages, which consist of the ability to get big size and uniform area, quickly define figure type, have high resolution capabilities, and faster film-forming process speed, for the piezoelectric type inkjet printing technology. In addition, the adjustable parameters and voltage can achieve more accurate ink jet and also reduce the loss of material. We can use its advantages to discover this study. 　　In the study of quickly define figure type, which can be used in the place of Photolithography, the ink droplets of Au nanoparticles (AuNP) 10~15nm solution are utilized in this study and the ITO surface are adjusted by the use of surface modification treatment. The ITO glass substrates are immersed and soaked in the hydrochloric acid solutions with different proportions, so that the suface contact angle between ITO thin-film electrodes and AuNP ink droplets can be improved to demonstrate the hydrophilic surface (10° < θ < 80°). In the inkjet printing process, AuNP ink droplets can be uniformly diffused, so that the ink droplets can overlap. 　　The inkjet printing with the use of Au nanoparticles (AuNP) 10~15nm can be applied in the basic structure of the OLED optoelectronic devices. First, the Au nanoparticles (AuNP) can be inkjet printed directly onto the surface-modified ITO glass substrates. Then a conventional structure of green OLED can be further prepared by using thermal evaporation system. The related optoelectronic characteristics can be measured and analysed. Due to the fact that the particle size of the used Au nanoparticles (AuNP) solution is less than 100nm, it exhibit wine red. However, the surface plasma resonance absorption wavelength of the gold nano-spheres are distributed in the range of 510−535nm according to the different sizes (10 to 25nm). In the literature, the working potential of Au nanoparticles (AuNP) with the particle size of approximate 5~25nm is in the HOMO of 5.1 to 5.2 eV, while the working potential of the ITO thin film electrode is in HOMO of 4.7~4.8 eV. Therefore, the Au nanoparticles (AuNP) can be served as a good hole injection layer (HIL), or the HOMO energy level character of ITO with the use of the Au nanoparticles (AuNP) can be also modified.