Roof Filling Mechanism During Thermal Bonding Of Polymer-based Mirco-nanochannels

In recent years, the research on basic and technology related with micro- nanochannels has become the noticeable front filed. The fluid and molecular transport in micro-nanochannels have a specific nature of property and the related research already has some breakthrough different from the traditional theory. Thermal bonding is the key technology to achieve sealed polymer micro– nanochannels. The research on thermal bonding mechanism is of great significance on making micro-nanochannels successfully and controling the size exactly.The micro-nanochannels based on SU-8 polymer are made in this paper using PDMS mold through soft imprinting method. In the process of thermal bonding, experiments are carried out under different conditions such as variable polymer thick,temperature, channel width and time. Filled patterns are observed using a sanning electron microscpy and the roof filling machenism under each condition is analyzed. The finite element software FLUENT is used for numerical analysis and the numerical results of roof filling process exhibites a similar tendency as the experimental results which confirms that the polymer moves actually under the capillary during the bonding process.The roof filling mechanism and its controlling method has been studied in this paper. The research is of important theoretical significance and practical value for the further study of science problems in the process of fabricating polymer micro-nanochannels and also the application in most field.