硅化学腐蚀片电容法测厚与机械法测厚差异的原因分析

摘要

在硅片厚度测量工作中，发现硅化学腐蚀片采用机械测厚和电容法测厚所得的数据存在差异，通过一系列对比实验对这一差异产生的原因进行了合理分析。首先，以硅抛光片作为对比，分别测试了硅抛光片与硅化学腐蚀片在采用两种测厚方法测厚时的数值并计算出其差值。针对这一差值，在分别对硅化学腐蚀片及硅抛光片的表面状况进行分析后，认为较粗糙和平整度较差的表面状况是造成硅化学腐蚀片采用电容法测厚与机械法测厚出现差异的主要原因。%It was found that the thickness test results of etched wafers were regularly different when measured by mechanical method and capacitance method and this difference was studied reasonably. Firstly, taking polished wafers as contrast, the value and surface of etched wafers and polished wafers were tested and analyzed respectively. Considering above two aspects, the rough surface of etched wafers was thought the main reason why the thickness test results were different.