Efficient fabrication of ultrasmooth and defect-free quartz glass surface by hydrodynamic effect polishing combined with ion beam figuring.
Efficient fabrication of ultrasmooth and defect-free quartz glass surface by hydrodynamic effect polishing combined with ion beam figuring.
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DOI：
10.1364/oe.22.013951
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发表时间：
2014-06
期刊：
影响因子：
3.8
通讯作者：
Wen-qiang Peng;Chao-liang Guan;Shengyi Li
中科院分区：
文献类型：
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作者：
Wen-qiang Peng;Chao-liang Guan;Shengyi Li
在流体动力效应抛光中，材料去除率的大小很大程度上取决于工件表面的切应力和动压力的分布。流体动力学模拟结果表明，转速越高，间隙越小，材料去除率越大。分子动力学（MD）计算表明，氧化硅纳米颗粒中的Si-O键合能比石英玻璃中的Si-O键合能强，因此吸附的氧化硅纳米颗粒可以将原子从石英玻璃表面拖走。由于高能物理去除率极低，不能有效去除深亚表面损伤。然而，亚表面损伤层可以通过离子束刻蚀（IBF）快速去除，并且在表面上留下包含钝化划痕和凹坑的较薄层。钝化层很薄，在大间隙条件下，可以用低材料比的HEP工艺去除。与IBF工艺相结合，HEP工艺后的亚表面损伤和表面划痕得到了有效的去除。加工表面无明显的重复痕迹，表面粗糙度提高到0.130nm rms，0.103nm Ra。
Material removal rate has greatly relied on the distribution of shear stress and dynamic pressure on the workpiece surface in hydrodynamic effect polishing (HEP). Fluid dynamic simulation results demonstrate that the higher rotation speed and smaller clearance will cause the larger material removal rate. Molecular dynamic (MD) calculations show the bonding energy of Si-O in the silicon-oxide nanoparticle is stronger than that in the quartz glass, and therefore the atoms can be dragged away from the quartz glass surface by the adsorbed silicon-oxide nanoparticle. The deep subsurface damage cannot be efficiently removed by HEP due to its extremely low removal rate. However, the subsurface damaged layer can be quickly removed by ion beam figuring (IBF), and a thinner layer containing the passivated scratches and pits will be left on the surface. The passivated layer is so thin that can be easily removed by HEP process with a low material rate under the large wheel-workpiece clearance. Combined with the IBF process, the subsurface damage and surface scratches have been efficiently removed after the HEP process. Meanwhile there are not obvious duplicated marks on the processed surface and the surface roughness has been improved to 0.130nm rms, 0.103nm Ra.