氮化铝基片超精密加工的实验研究

Experimental Study on the Ultraprecision Machining Technology of A1N Substrate

氮化铝材料具有较高的热导率和良好的介电性能,机械强度高,热膨胀系数与半导体硅材料相近,非常适于制造大功率或快速半导体器件的散热基片和封装材料。本文采用游离磨料加工方法对氮化铝基片表面进行了研磨、抛光, 讨论了不同加工参数对试件表面粗糙度和材料去除率的影响。采用表面粗糙度仪和厚度仪分别对超精密加工后AIN基片的表面粗糙度及去除厚度进行了测量。实验结果表明,在本实验条件下可以获得表面粗糙度Ra为8nm的超光滑表面。实验还采用XJZ-5型电子显微镜对加工过程中AIN的表面结构进行了观察,分析了不同超精密加工阶段的材料去除机理,同时发现晶粒间孔隙会降低AIN基片的可加工性能。

Aluminum nitride (AIN) substrate has been recognized as one of ihe most promising electronic substrate as heating panel and packaging materials for its high thermal conductivity, fine electrical insulation, and close coefficient of thermal expansion to silicon semiconductor. In this study, the AIN substrate is lapped and polished lo make the surface quality improved, and the influence of the different machining parameters on the surface roughness and material removal rate of AIN are discussed. The surface texture is observed by microscope ( XJZ - 5 ) , and the surface roughness is measured by Pethometer S2 ( Maer Co. ). An extremely smooth surface with roughness Ra 8nm is obtained by the ultraprecision machining process. It is also found that the gap between grains will decline the machinability of AIN substrate.