本文利用壓電致動器在刀具上產生橢圓振動，並以此振動劃切硬脆材料劃切形成振動輔助劃切。文中以鑽石刀劃切單晶矽，觀察振動輔助劃切與傳統劃切對矽的延脆轉變深度的大小，以及加工後在脆性破壞區及延性切削區的表面粗糙度。
硬脆材料的臨界切深與材料及刀具幾何有關，而本文使用的鑽石刀劃切矽之臨界切深為0.17μm，而在振動輔助劃切時，臨界切深會隨進給速度下降與切深方向振幅增加而增加，以進給速度10 μm/s、切深方向5μm的振動輔助劃切單晶矽，延脆轉變深度可達2μm，此值為傳統劃切的10倍。
振動輔助切削與傳統劃切在脆性破壞區時，溝槽底面的表面粗糙度Ra分別為0.3μm與0.9μm，Rmax分別為4 μm~10 μm及10 μm~14 μm。藉由振動輔助劃切可以降低矽的裂紋長度，使表面比傳統劃切平整。

關鍵字：振動輔助劃切;延脆轉變深度;臨界切深;硬脆材料

This thesis combines the elliptical tool vibration and brittle materials scribing process to generate vibration-assisted scribing. We use the vibration that is produced by the piezoelectric actuator to make the elliptical vibration on the tool. In this thesis, we select diamond tool to scribe silicon. This thesis also investigates the difference of brittle-ductile transition depth and surface roughness Ra, Rmax on finished silicon in both brittle and ductile regime between vibration-assisted scribing and traditional scribing.
The critical depth of cut (CDC) depends on material properties and tool geometry. The CDC is 0.17 μm as using the diamond tool we choose to scribe silicon, and CDC increase as feed rate decrease or cut depth vibration increase in vibration-assisted scribing. At feed rate 10 μm/s and cut depth vibration 5μm condition, CDC is 2 μm as 10 times than traditional scribing.
Compared with vibration-assisted scribing and traditional scribing in brittle zone, the surface roughness Ra is 0.3 μm and 0.9 μm respectively, and Rmax¬ is 4 μm~10 μm and 1 0μm~14 μm respectively by vibration-assisted scribing, the surface will be smoother than traditional scribing process in brittle zone because vibration-assisted scribing reduce the crack growth.

keywords:vibration-assisted scribing;brittle-ductile transition depth;brittle material;critical depth of cut (CDC)

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