Al膜的微孔阵列湿法腐蚀技术研究

微通道板(Microchannel Plate,MCP)是像增强器中实现电子倍增的关键器件。以硅为基体制备的微通道板相对于传统的微通道板在性能方面有很大的提高。在对硅进行反应离子深刻蚀(DRIE)前,需要对充当掩蔽层的金属铝膜进行湿法腐蚀。对于掩模图形为孔径10 m、孔间距5 m的大面阵的微孔阵列,在腐蚀过程中,微孔孔径较小导致溶液对流困难且反应生成物H2极易吸附在反应界面上,影响反应物质的输送和化学反应的进行。如果腐蚀参数不合适,阵列式微孔图形会出现随机腐蚀、不完全腐蚀、过腐蚀等现象。通过加入表面活性剂,减小溶液中表面应力,可以促使反应物H2排出。同时通过逐一控制变量,研究了腐蚀液浓度、腐蚀液温度和腐蚀时间对腐蚀结果的影响。结果表明,腐蚀速率与腐蚀液浓度、腐蚀液温度成正比。通过参数优化,得到了最佳的腐蚀参数。此时图形完整,尺寸准确,解决了微孔阵列的图形化问题。

Al micropore array wet etching

Microchannel plate is the key component of the image intensifier. Compared with traditional MCP, Si-MCP has a great improvement in performance. Before DRIE in Si, the wet etching is necessary in the Al film. As the film pattern was the big area and periodic micropore with the pore of 10 m, the pitch of 5 m, the micropore resulted in the H2 absorbing on the reaction interface easily and affecting on the reaction. Meanwhile, the arrayed micropore pattern would appear random corrosion, incomplete corrosion and over etching because of the inappropriate corrosion parameters. By adding surfactants, the surface stress can be reduced, which can promote the reaction H2 discharge. By individually controlling variable, the affects of the corrosive concentration, temperature and the etching time on the result were focused. The results shows the corrosion rate is proportional to the corrosive concentration and temperature. By optimizing parameters, the best corrosion parameter is got. The pattern is complete and the size is accurate. The pattern of the arrayed micropore is solved which has a important significance to the DRIE.