微电铸中电流-流体耦合的数值分析及实验

Numerical analysis and experiment of current-fluid coupling in micro-electroforming

研究了LIGA/UV-LIGA的核心技术微电铸的内在规律,对影响铸层生长的阴极电流密度和流体流场进行了数值分析。以微流控芯片微模具上的十字电铸层为研究对象,建立了微电铸的数学模型。给出了描述微电铸体系电流密度和流体流场的偏微分方程,运用有限元法对微电铸体系进行三维数值仿真,得到了电流密度分布和流体流场分布的数值结果。选择十字铸层上的测量点,由该点处电流密度和流体流速仿真数据计算出微电铸4 h的铸层生长高度仿真值,并与相同工艺条件下的微电铸实验铸层生长高度进行对比。结果显示,对应各测量点微电铸生长高度仿真值和实验值的变化趋势接近,绝对偏差小,最大绝对偏差为4.437μm,最小绝对偏差为0.264μm。实验表明这种数值仿真方法适用于微电铸工艺设计的辅助分析,可缩短微电铸工艺的开发周期。

The cathode current density and the fluid field relevant to the growth of electroforming layer is studied with numerical analysis to explore the inherent laws of micro-electroforming that is a key technology of research objec UV-LIGA. By taking the crossing electroforming layer of a micro-fluidic chip mold as a t, a mathematical model is established. Then,the current density and the fluid field are described with partial differential equations, and the 3D numerical simulation of the micro-electroforming system is performed density distribution and fl ming layer, the simulated with the finite elemen uid field distrib t method Choosing to obtain measurln the simulated results of the current g points on the crossing electrofor- growth height during 4 hour electroforming is calculated based on the simulated data of current density and fluid velocities at the measuring points. Finally, the simulated growth height of electroforming layer is compared with that gotten from the micro-electroforming ex- periment under the same technological condition. The results indicate that the simulated one of electroforming layer is close to the experimental growth height to every measuring point and show low absolute deviations in a maximum of 4. 437μm and a minimum of 0. 264 μm. These results also indicate that the numerical simulation can be used in the analysis and design of micro-electroforming, and can reduce the developing time of micro-electroforming technology.