兆声波精密微电铸设备及相关工艺研究

Research of Megasonic Assisted Micro Electroforming Process Based on a Novel Megasonic Reactor

兆声波具有高声强、低空化、声流扰动的特点,将其应用于电化学沉积领域有着明显的优势。设计了一种贴片式双向兆声辐照的兆声波反应器,组合其他功能模块,制作了一款集成化的兆声精密电铸设备。以铜基底上镍的电沉积过程为研究对象,考察了不同兆声波作用形式对铸层厚度均匀性及表面形貌的影响,对比了无兆声作用、单侧兆声作用、双侧交替兆声作用下的电铸层厚度均匀性及电铸层表面形貌。电铸完成后,镍铸层的平面度值分别为:无兆声15.03μm、单侧兆声15.36μm、双侧兆声10.91μm。单侧兆声振动产生的驻波条纹及偏向推积现象影响了铸层的厚度均匀性及表面形貌。双侧交替兆声辐照克服了单侧兆声作用存在的偏向推积问题。相对于无兆声作用及单侧兆声作用,双侧兆声辅助电沉积获得了更均匀的电铸层厚度以及更好的沉积层表面形貌。

Megasonic has obvious advantages in overcoming the limitations of micro-electroforming process because of its low cavitation effect, high sound intensity and acoustic streaming. In this work, a bidirectional surface mount device (SMD) megasonic electrolytic bath was designed. And an integrated megasonic electroforming equipment was designed and made considering of other components of an electroforming reactor. Single directional megasonic assisted electrodeposition and bidirectional megasonic assisted electrodeposition was investigated, respectively. Besides, a traditional deposition of nickel was conducted as the control group. The results show that the planeness value (PV) of electrodeposited layer is 15.03μm without megasonic wave, and the PV of nickel electrodeposited layer is 15.36μm with single directional megasonic assisted. The bidirectional megasonic wave assisted electrodeposition has a planeness value 10.91μm, which obtained the most uniform electrodeposited layer among these three different electrodeposition conditions. Besides, bidirectional megasonic wave assisted electrodeposition can achieve better surface morphology than other conditions.