数片硅同时自停止腐蚀技术研究

Study of Simultaneous Electrochemical Etch-Stop of Multiple Silicon Wafers

本文从理论和实验上证明了数片硅同时自停止腐蚀的可行性。结果表明:KOH溶液非常适用于该技术;当几片硅同时进行电化学腐蚀时不会互相影响;而且当它们的开路电位(OCP)、钝化电位(PP)以及各片硅腐蚀完成的时间均有差别时,都能有效地实现自停止。实验以4片硅同时自停止腐蚀为例,最后所得的4片硅膜厚相差不到1μm。

In this paper, the feasibility of simultaneous electrochemical etch-stop of multiple silicon wafers is proven in both theory and experiments. It is shown that KOH is very suitable for this application, silicon wafers do not affect one another when etched at the same time, even if their open-circuit-potential (OCP), passivation-potential (PP) and time of etch stop are not the same, their etch-stop can all be realized successfully. In the experiment, the difference of thickness of the four sample silicon membranes is not more that 1.