喷墨打印OLED发光层像素坑内成膜控制方法  

Forming control method of inkjet printing OLED emitting layer pixel pit film

作　　者：朱红 陈建魁[1] 岳晓 熊镜凯 熊佳聪 高国雄 ZHU Hong;CHEN Jian-kui;YUE Xiao;XIONG Jing-kai;XIONG Jia-cong;GAO Guo-xiong(State Key Laboratory of Digital Manufacturing Equipment and Technology,School of Mechanical Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;Wuhan National Innovation Technology Optoelectronics Equipment Co.,Ltd.,Wuhan 430078,China)

机构地区：[1]华中科技大学机械科学与工程学院数字制造装备与技术国家重点实验室,湖北武汉430074 [2]武汉国创科光电装备有限公司,湖北武汉430078

出　　处：《液晶与显示》2022年第11期1420-1429,共10页Chinese Journal of Liquid Crystals and Displays

基　　金：国家重点研发计划(No.2018YFA0703203);广东省重点领域研发计划(No.2019B010924005);国家自然科学基金面上项目(No.51975236)。

摘　　要：在OLED发光层喷墨打印制备中,像素坑内成膜厚度控制是抑制器件产生Mura缺陷的关键。不同喷孔液滴体积差异和液滴错误沉积引起的像素坑内融合溶液体积变化,是造成发光层膜厚不一致的主要原因。为解决膜厚一致性问题,本文提出了基于液滴体积控制与沉积定位控制的OLED发光层成膜控制方法。首先调节驱动波形使不同喷孔产生体积适配的液滴;然后检测各喷孔的液滴落点位置,通过偏移补偿和异常喷孔筛选控制液滴精准沉积;最后使用不同液滴混合方法控制像素坑内溶液体积。在实验中,将液滴沉积定位偏差控制在±10μm,将液滴混合后溶液体积差异控制在±4%,测量干燥固化后的薄膜厚度,结果表明,不同像素坑膜厚一致性提高至95%以上,获得了发光均匀的OLED器件。本文提出的膜厚一致性控制方法达到预期、满足OLED功能层制备要求。When the OLED emitting layers are produced by using the injet printing method,the film thickness of different pixel pits can cause Mura defects in the light-emitting devices. The main reason for the film thickness variation is the difference of ink volume in different pixel pits caused by the inconsistent droplet volume of different nozzles and the wrong deposition of droplets. To solve the problem of film thickness consistency,a film forming control method for OLED emitting layer based on droplet volume control and deposition position control is proposed. Firstly,the driving waveform is adjusted so that the droplets with appropriate volume can be generated from nozzles. Then,the droplet landing position of each nozzle is detected,and the deposition position of droplets is controlled by the offset compensation and abnormal nozzles screening. Finally,the ink volume in the pixel pit is controlled by droplets mixing method. In the experiment,the deviation of droplet landing position is controlled within ±10 μm,and the volume difference of the ink is controlled within ±4% by droplets mixing method. The film thickness of the emitting layer after drying is measured. The experimental results show that the consistency of different pixel pit film thickness is more than 95%,and the OLED device with uniform light emission is obtained. The film thickness consistency control method can meet the manufacturing requirements of OLED functional layer.

关 键 词：喷墨打印 OLED 成膜控制 体积控制 沉积定位 膜厚一致性 

分 类 号：TN383.1[电子电信—物理电子学] TN05