喷墨打印高精度图案研究进展

Research Progress of High-precision Patterns by Directly Inkjet Printing

近年来,功能材料的图案化及其在高性能光电器件的应用研究受到了广泛关注.与传统图案化方法相比,喷墨打印技术更容易实现大面积复杂图案的直接书写和复合功能材料的图案化,且制备简便,成本低廉,使其成为最受关注的图案化方法之一.综述了近年来喷墨打印制备高精度图案的研究进展.包括通过优化墨滴的化学组成、调控基材的化学或物理结构以及改进喷墨设备等方法以提高喷墨打印分辨率;以及通过控制液滴内部的毛细流动和三相接触线的移动抑制喷墨液滴的"咖啡环"效应,以实现均质打印.文章最后展望了喷墨打印制备高精度图案的研究发展方向.这些工作对于实现高性能器件的制备具有重要意义.

High-precision patterns have aroused wide attention due to their important applications in high-performance op- tical/electrical devices. By virtue of easy and direct writing of desired pattems, high throughput and low-cost, inkjet printing has become one of the most promising candidates for the manufacture of patterns, compared with conventional approaches such as photolithography, microcontact printing. Various materials can be precisely deposited on target positions. As a pri- mary focus, improving the precision of printed pattems would greatly enhance the performance of the devices. So far, various approaches have been developed for improving the printing precision. Pattern resolution is limited by the volume of jetted droplet and the area of droplet spreading on substrate. Finer resolution can be achieved through reducing the deposition di- mension, i.e. optimization of the chemical composition of ink, chemical/physical modification of substrates, and improve- ment of printing apparatus. Besides, uniform deposition of functional materials is also essential for fabricating high-precision patterns and high-performance devices. ＂Coffee ring＂ is a common phenomenon during the drying process of droplets, which is generated due to the pinning three phase contact line （TCL） and the outward capillary flow in an evaporating droplet. Therefore, homogenous deposition without ＂coffee ring＂ effect can be realized by tuning the capillary flow in the droplet and controlling the movement of the TCL as the droplet evaporating. In this paper, we presented the recent research progress for achieving high-precision patterns by inkjet printing, including minimizing the deposition dimension to improve the resolution and avoiding the ＂coffee ring＂ effect to achieve high uniformity. These reports will probably promote the development of novel and facile method for high-precision inkier printing. New trends and research perspectives were briefly discussed at the last section of this review.