Study Of Micro Pit Array Mold By Mask Electrochemical Etching

As the rapid development of MEMS technology, the microfluidic chip is increasingly demanded in the emerging fields, such as the cell biology, the analysis of water pollution, protein separation. Meanwhile, more and more attention is paid to the mask electrochemical etching technology, which is an important part of the production technology of metal mold. The primary work of this paper mainly concentrates on the fabrication processes of micro pit array mold, whose material contain the stainless steel and nickel metal. The research result provides process reference for relevant technologies in metal mold production field.The current density distribution rule of single mcro pit and mcro pit array by the finite element analysis is introduced. At first, this paper modeled about single mcro pit and mcro pit array respectively, whose mask aperture were 50μm and 100μm separately. Then, the current density was 5A/dm2 by setting boundary and loading conditions. Finally, the distribution rule of anode current density could achieve by solving and post-processing. In a word, the simulation results could direct the etching experiment.It is researched that the mask electrochemical etching technology processes stainless steel. Firstly, this paper regarded BN308 photoresist as the mask, and experiments were made to analyze the effect of the polishing process on uniformity of the etching. Then, the influence of pickling on the substrate was researched, and it was found that pickling could improve the etching uniformity, and then precipitation problem was solved effectively by adjusting the pH of the solution. At last, the uniformity of micro pit could be improved by adopting high-low current density (10A/dm2、5A/dm2)It is researched that the mask electrochemical etching technology machines nickel. At first, the influence of mask aperture and current density on the etching uniformity was researched quantitatively by using the variation coefficient. Then, the uniformity of micro pit array could be boosted by substrate polishing and pickling process, and precipitation problem was solved effectively by adjusting the pH of the solution.It is researched that the mask electrochemical etching technology machines grooves mold. This paper introduced that the grooves mold with different line width were machined by the mask electrochemical etching technology, and discussed the amount of lateral erosion and etching coefficient of the grooves with different line width.