An inkjet printed quantum dot (QD) color conversion layer needs to be a few micrometers thick to successfully block blue light leaking from the organic light‐emitting diode (OLED). To control the thickness of the QD film in the pixel, we investigated modifying the surface wettability of both the substrate and bank by hydrophobic octadecyltrichlorosilane (OTS) treatment. Without the OTS treatment, the printed QD droplets came to the bank before the pinning process and excessive pile-up occurred, pushing them over the bank wall. However, with OTS surface treatment, the contact angle of the QD ink was increased from 16° to 38° on the substrate and from 59° to 89° on the bank. By reducing the contrast in hydrophilicity and hydrophobicity between the substrate and bank, the pile-up phenomenon was remarkably reduced. This allowed us to control the thicknesses of the QD layers by changing the number of printed drops of QD ink. As the thickness of the QD film increased from 1 μm to 9 μm, the CIE chromaticity coordinates of the spectrum changed from (0.173, 0.437) to (0.265, 0.648) moving from sky blue-green to nearly pure green.

喷墨印刷的量子点（QD）颜色转换层需要为几微米厚，才能成功阻挡从有机发光二极管（OLED）泄漏的蓝光。为了控制像素中QD膜的厚度，我们研究了通过疏水性十八烷基三氯硅烷（OTS）处理来改变基材和堤岸的表面润湿性。如果不进行OTS处理，则打印的QD液滴会在钉扎过程之前到达堤岸，并发生过多堆积，将其推到堤岸壁上。但是，通过OTS表面处理，QD墨水在基材上的接触角从16°增加到38°，在堤岸上从59°增加到89°。通过降低基材和堤岸之间的亲水性和疏水性的对比度，显着减少了堆积现象。这使我们能够通过更改QD墨水的打印液滴数来控制QD层的厚度。随着QD膜的厚度从1μm增加到9μm，光谱的CIE色度坐标从（0.173，0.437）变为（0.265，0.648），从天蓝色变为绿色。