应用CVD金刚石涂层工具研磨单晶蓝宝石

通过热丝化学气相沉积(HFCVD)法制备了具有球状晶结构、棱锥形晶结构和棱柱形晶结构等3种不同表面特征的化学气相沉积(CVD)金刚石涂层工具,以提高其研磨效率。通过正交实验法研究了金刚石涂层晶粒形态、载荷、工作台转速、研磨时间等4个工艺参数对蓝宝石材料去除率和表面粗糙度的影响。结果表明:金刚石涂层的晶粒形态对材料去除率和表面粗糙度影响较大;球状晶结构金刚石涂层切向力较小,棱柱形晶结构金刚石涂层切向力较大;选择棱柱形晶CVD金刚石涂层工具研磨蓝宝石,在研磨加工参数为载荷0.15 MPa、转速100 r/min、研磨时间3 min时,其材料去除率为0.397μm/min,表面粗糙度为0.354μm。结果表明:提出的CVD金刚石涂层工具可用于进一步加工、研磨蓝宝石切片,去除其表面划痕,从而改善工件表面质量。

Lapping of sapphire wafers by CVD diamond coated tools

Three kinds of Chemical Vapor Deposition(CVD) diamond coated tools with different surface morphologies(including spherical structure crystal, incisive pyramid crystal and quadrangular prism crystal) were prepared by Hot Filament Chemical Vapor Deposition(HFCVD) method to improve the lapping efficiency of CVD diamond coated tools in sapphire wafer processing. The influences of process parameters such as diamond coating grain morphology, lapping load, velocity of operating platform and lapping time on the removal rates and surface roughnesses were researched The results show that the diamond coating grain morphology has great impact on the material removal rate and surface roughness. Moreover, the diamond coated tool with spherical crystal structure has a lower tangential force, while the diamond coated tool with quadrangular prism structure offers a higher tangential force. When the diamond coated tool with quadrangular prism structure is selected to lap sapphire wafers, and the process parameters are lapping load in 0.15 MPa, the velocity of operating platform in 100 r/min and lapping time in 3 min, the maximum material removal rate reaches to 0.397μm/min and the surface roughness is 0.354μm. It concludes that the CVD diamond coated tools are suitable for machining and lapping sapphire wafers and can remove the scratches on the surface of sapphire wafers and improve their surface qualities.