The Application Research Of Atmospheric Pressure Plasma In Material Deposition And Surface Functionalization

With the rapid development of material science and the flexible electronics,it is a hot topics to develop different kinds of new technologies for material preparation and surface functionalization.The plasma is widely used in materials science and integrated circuit manufacturing process.Due to the traditional plasma deposition and modification equipment working under the low pressure,the specifically designed vacuum systems are always needed to maintain the environment which lead to the high facilities and operation cost,which greatly limits the application range of plasma.A few atmospheric pressure-based plasma devices are mainly for large-scale material modification.For the small dimension selective surface modification,a masking based on lithography process is always required.According to the main characteristics of atmospheric pressure plasma,atmospheric pressure plasma jet(APPJ)was firstly selected to study the plasma-enhanced material deposition and sensor construction.Then,surface dielectric barrier discharge plasma was studied for the plasma surface modification and in-situ deposition process with high efficiency,low manufacturing cost on flexible polyimide substrate.The main research contents include:Firstly,the simple and rapid preparation of ZnO semiconductor thin films was realized by APPJ.In the experiment,with zinc nitrate as the precursor,the preparation of ZnO thin films was successfully carried out by aerosol assisted method under nitrogen plasma.And the resulted ZnO films were employed to construct the humidity sensor.The characterization of the ZnO thin films and the humidity sensors indicated that APPJ can be used to deposit the solid films selectively at atmosphere pressure,which was proved to have a broad prospect in the roll-to-roll sensor preparation process.Secondly,the plasma generator based on surface micro discharge of surface dielectric barrier discharge(SDBD)is discussed emphatically.The SDDB plasma generator can be used for the surface sterilization and modification of material.The plasma generators with different electrode configurations(rectangular,circular,and hexagonal)were designed,and their effects on the parameters like plasma distribution,dissipation power and temperature characteristics were analyzed and compared.The results showed that the different electrode structure has different plasma distribution forms,and the dissipation power of the plasma can be adjusted by the effective area ratio of the discharge region.By spectral analysis,the measured electron temperature is about 15785K,which is much higher than the plasma gas temperature.Thirdly,combined with the research results of SDBD,the selective plasma modification technology,i.e.,plasma stamp printing technique,is discussed.With the patterned SDBD plasma arrays as stamp,the hydrophilicity and surface energy of PI were tuned.The size effect of SDBD plasma arrays on the final plasma homogeneities were characterized,and the limit of plasma printing was obtained.In addition,based on the SDBD plasma stamp printing technique,the rapid selectively modification of the PI surface was successfully achieved.Lastly,the SDBD enhanced material deposition was discussed.The in-situ ZnO atmospheric deposition on PI surface was successfully realized by employing the annealing characteristic of plasma,and the feasibility of SDBD plasma in the field of flexible electronic device was discussed through the combination with humidity sensor.The related technologies discussed in this paper are of great reference value for future plasma applications in the field of material preparation,new flexible electronic devices and non-masked surface modification.