The Key Techniques Research Of Polymer Microfluidic Chips Mould For Hot Embossing Molding

Microfabrication techniques are the fundation and precondition of MEMS development.Based on the traditional photolithography and etching process, the new technologies and materials have been widely used in microfabrication with the evolution of microelectronics industry, semiconductor integrated circuit, and precision machinery equipment. The polymer materials have a lot of advantages other materials incomparable, which provided with great market value and potential in non-silicon production for high quality and reasonable price.In the basis of new materials introduction,new process gradually begins to growth.At the same time, Many kinds of polymer processing methods develop quickly.Hot embossing is an effective means of lot size manufacturing with the advantage of operation and controlling simply.The quality of hot embossing mould is the key factor of polymer chips molding seriously influencing microstructure morphology.UV-LIGA technique with low cost is a standardized procedure. It can be used to make metal microstructure widely used and commonly concerned in the microfabrication field.The paper is order to making polymer microfluidic for target based on UV-LIGA.Both ultraviolet thick lithography technology and micro electroforming in UV-LIGA process are the key technologies. They are discussed aiming at fabrication photoresist and metal mould,and the new process is also explored. The paper is organized as following:In the first section,Based on the theoretical analysis,The paper reviews the generation, development and application situation at home and abroad about the ultraviolet thick film lithography technology and micro electroforming process. According to the existing process were discussed, the characteristics and application scope of ultraviolet thick film lithography techniques and micro electroforming are analyzed.In the second section,The principle and process concept involved are discussed through the theoretical analysis of the ultraviolet thick film lithography technology. And the theoretical models are established.The characteristics and lithography technical parameters of thick film photoresist mainly including coating, soft baking, exposure, and development are discussed. The orthogonal test method is used to arrange thick film photolithography experiments on the appropriate working conditions. To get optimized parameters,The results are analyzed through the extreme difference method,which can be applicable to the positive AZ4620 lithography process parameters.In the third section,The condition that the properties of positive photoresist changes at high temperature is verified.The multi-layer photoresist structure is make with the experiment.On the basis of AZ4620 hard baking process,plasma oxygen etching, and thick film ultraviolet lithography technologies are combined to fabricate the photoresist mould with multi-layer structure.In the last section,The foundation of electrochemical study is the theory of electrodeposition ,which is the key factors of micro electroforming.The finite element software simulates the condition of electric field and flow field of electrolytic solution. The current and environmental parameters are adjusted with the help of reasonable control of system parameters and conditions.In the end,the nickel mould is produced.