Micro-Fabrication by Using Combination Technique of Nano-scale Machining and Alkaline Etching

采用摩擦力显微镜（FFM）机理加工的单晶硅（100）表面，在KOH溶液的腐蚀作用下，对加工区域产生遮蔽效应。在本研究中，研究了这一现象的机理和利用这一现象制造微结构的方法。此外，通过控制纳米尺度的加工条件，进行了三维微观结构的制备研究。利用透射电镜、激光拉曼光谱等对加工区域进行了分析。结果发现，在加工表面下存在一层低晶层。在第一层下存在有晶体位错的影响层。从这些结果可以看出，当KOH溶液的浓度小于20%时，低晶层具有掩蔽效应。另一方面，当KOH浓度大于20%时，晶体位错影响层的蚀刻效果增强。在刻蚀过程中加入超声波可以改善表面粗糙度和结构形状。通过控制加工线的正常负荷和节距条件，改变了FFM加工区域的掩蔽效应。利用该技术制备了三维微结构。今后，将通过开发加工悬臂梁和优化加工条件，对高精度结构的制造进行研究。

Masking effect was appeared to the processing region when the (100) surface of single crystal silicon processed by using the mechanism of friction force microscope (FFM) was etched by KOH solution. In this research, mechanizm of this phenomenon and method to fabricate the microstructure by utilizing this phenomenon was researched. Moreover, the research to fabricate 3D microstructure was carried out by controlling nano-scale processing conditions.Processing region was analyzed by TEM, Laser Raman spectroscopy and etc. As a result, it was found that there is a low crystalline layer under the processing surface. And there is affected layer with crystal dislocation under the first layer. From these results, masking effect was provided by low crystalline layer when concentration of KOH solution is less than 20 wt%. On the other hand, enhanced etching effect was provided by affected layer with crystal dislocation in higher concentration of KOH solution more than 20 wt%. Surface roughness and shape of structure was improved by addition of ultrasonic wave in etching process. Moreover, masking effect of FFM processing region was changed by controlling the condition of normal load and pitch of processing line. By utilizing this technique, 3D micro-structure was fabricated. In the future, research about fabrication of higher precision structure will be carried out by development of machining cantilever and optimization of processing condition.