大气等离子体抛光技术在超光滑硅表面加工中的应用  

Application of atmospheric pressure plasma polishing method in machining of silicon ultra-smooth surface

作　　者：张巨帆[1] 王波[1] 董申[1] 

机构地区：[1]哈尔滨工业大学精密工程研究所,黑龙江哈尔滨150001

出　　处：《光学精密工程》2007年第11期1749-1755,共7页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.50535020);武器装备预研基金资助项目(No.9140A180202-06HT0132);黑龙江省自然科学基金资助项目(No.E200622)

摘　　要：发展了大气等离子体抛光方法,并用于超光滑表面加工。该技术基于低温等离子体化学反应来实现原子级的材料去除,避免了表层和亚表层损伤。运用原子发射光谱法证明了活性反应原子的有效激发,进而揭示了特定激发态原子对应的电子跃迁轨道。在针对单晶硅片的加工实验中,应用有限元分析法在理论上对加工过程中的空间气体流场分布和样品表面温度分布进行了定性分析。后续的温度检测实验证实了样品表面温度梯度的形成,并表明样品表面最高温度仅为90℃。材料去除轮廓检测结果符合空间流场的理论分布模型,加工速率约为32 mm3/min。利用原子力显微镜对表面粗糙度进行测量,证实了加工后样品表面在一定范围内表面粗糙度Ra=0.6 nm。最后,利用X射线光电子谱法研究了该方法对加工后表面材料化学成分的影响。实验和检测结果均表明,该抛光方法可以进行常压条件下的超光滑表面无损抛光加工,实现了高质量光学表面的无损抛光加工。Based on low temperature plasma chemical process, a novel non-contacting precision machining method, the Atmospheric Pressure Plasma Polishing （APPP） method, is developed. The APPP method utilizes the chemical reaction between the reactive plasma and the surface atoms to perform the atom scale removal process to avoid surface/subsurface defects. A self-fabricated system is built to implement this technology in the machining of ultra-smooth surfaces. As the key component, a capacitance coupling atmospheric pressure radio-frequency plasma torch is firstly introduced. By an atomic emission spectroscopic analysis, the atom component and relative densities of the plasma zone can be obtained. The subsequent theoretical analysis reveals that specific radical atom corresponds to certain electron transition state, which can indicate the different roles of various radical atom~ in the reaction process. In initial operations, silicon wafers are machined as samples. Before applying operations, both the temperature distribution on the workpiece surface and the spatial flow field distribution in the machining process are studied qualitatively by finite element analysis. Then the subsequent temperature measuring experiments demonstrate the formation of the temperature gradient on the wafer surface predicted by the theoretical analysis and indicate a peak temperature about 90℃ in the center. Using a commercialized form talysurf, the machined surface is detected and the results show regular removal profiles coincide well with the flow field model. Moreover, the removal profile also indicates a 32 mm^3/min removal rate. Using the atomic force microscopy （AFM）, the surface roughness of 0.6 nm for the machined surface is also obtained. Then the element composition and proportion are detected and analyzed by an X-ray photoelectron spectroscopy （XPS）. The results also demonstrate the occurrence of the anticipated main reactions. All the experiments have proved that this APPP method has a potential for fabrications of hig

关 键 词：大气等离子体抛光法 超光滑表面 单晶硅 电容耦合 

分 类 号：TN305.2[电子电信—物理电子学]