Lee Jun Yeub, Ju Byeong-Kwon, Cho Kwan Hyun
Digital Transformation R&D Department, Korea Institute of Industrial Technology, Ansan-si 15588, Gyeonggi-do, Korea.
Display and Nanosystem Laboratory, School of Electrical Engineering, Korea University, Seoul 02841, Seoungbuk-gu, Korea.
Nanomaterials (Basel). 2022 May 9;12(9):1611. doi: 10.3390/nano12091611.
We implemented ultra-high resolution patterns of 2822 pixels-per-inch (PPI) via an inkjet printing and vacuum drying process grafted onto a sublimation transfer process. Co-solvented ink with a 1:1 ratio of N,N-dimethylformamide (DMF) to ortho-dichlrorobenzene (oDCB) was used, and the inkjet driving waveform was optimized via analysis of Ohnesorge (Oh)-Reynolds (Re) numbers. Inkjet printing conditions on the donor substrate with 2822 PPI microchannels were investigated in detail according to the drop space and line space. Most sublimation transferred patterns have porous surfaces under drying conditions in an air atmosphere. Unlike the spin-coating process, the drying process of inkjet-printed films on the microchannel has a great effect on the sublimation of transferred thin film. Therefore, to control the morphology, we carefully investigated the drying process of the inkjet-printed inks in the microchannel. Using a vacuum drying process to control the morphology of inkjet-printed films, line patterns of 2822 PPI resolution having a root-mean-square (RMS) roughness of 1.331 nm without voids were successfully fabricated.
我们通过将喷墨打印和真空干燥工艺嫁接到升华转印工艺上，实现了每英寸2822像素（PPI）的超高分辨率图案。使用了N，N - 二甲基甲酰胺（DMF）与邻二氯苯（oDCB）比例为1:1的共溶剂墨水，并通过分析奥内佐格（Oh）数 - 雷诺（Re）数来优化喷墨驱动波形。根据墨滴间距和行距，详细研究了具有2822 PPI微通道的供体基板上的喷墨打印条件。在空气气氛中的干燥条件下，大多数升华转印图案具有多孔表面。与旋涂工艺不同，微通道上喷墨打印薄膜的干燥过程对转印薄膜的升华有很大影响。因此，为了控制形态，我们仔细研究了微通道中喷墨打印墨水的干燥过程。通过真空干燥工艺来控制喷墨打印薄膜的形态，成功制造出了分辨率为2822 PPI、均方根（RMS）粗糙度为1.331 nm且无空隙的线条图案。
