| The superwettability surface is used to control the dewettability of liquid,so that the geometric shape and spatial distribution of its growth pattern can be programmed.This technique plays an important role in the preparation of large-area organic semiconductor micro-nano structure arrays with controllable pattern size.Pattern in the traditional organic photoelectric materials preparation methods,often appear unable to control led to the process of liquid evaporation of micro-nano structure in a variety of defects,in order to solve this problem effectively,this paper using the interface microstructure control and surface chemical modification of the two synergy,induced by fluid controllable segmentation and directional transport interface,Localized nucleation and localized growth of micro/nano structures are induced by domain limiting,and regular graphic preparation of large area organic materials is realized.At the same time,we developed the capillary liquid bridge induced dewetting assembly method.Driven by Laplacian pressure difference and capillary force,the capillary liquid flow can be oriented to mass transfer to ensure the targeted nucleation and directional growth of organic molecules,and patternization of organic materials can be prepared based on this method.The main research contents of this paper are as follows:(1)In order to enable the pattern to grow oriented,we developed the capillary liquid bridge induced dewetting assembly method.By designing silicon columns arranged in different morphologically,at the same time,the surface of the silicon column was modified with heptafluorodecyltrimethoxysilane to make the surface of the silicon column reach the state of hydrophilic top and hydrophobic side wall,so as to prepare the organic photoelectric functional materials pattern.In addition,we observe the dewetting process of liquid and the formation process of capillary bridge with the help of light microscope,analyze the force of liquid in different stages of dewetting process,and draw the conclusion that the biggest driving force is Laplace force.(2)Based on capillary liquid bridge self-assembly method,select different configuration solution of different concentration of organic matter,with the help of the silicon column template designed,using the method of liquid phase after a certain time of infiltration,successfully completed on the small size of silicon and quartz growth pattern,in determining the organic matter can achieve growth after a small area,using the same method to design to 4 inch size and name of quartz,Then the large area micro-nano structure array can be prepared.(3)The photoresist microcolumn template with smooth surface was firstly prepared by using the capillary liquid bridge to induce the dewetting process.The optimum size range was determined by the anti-swelling experiment,and the polymer C8-BTBT nanowire array with low defect density was successfully prepared by using the new sandwich structure of photo-resist template-solution-substrate.Based on this array,we fabricated an organic field-effect transistor and achieved an optical switching ratio of more than 10~7. |
