【作者】 刘玉岭； 檀柏梅； 牛新环； 赵海涛；

【Author】 LIU Yu-ling TAN Bai-mei NIU Xin-huan ZHAO Hai-tao (Hebei University of Technology,Tianjin 300130,China)

【机构】 河北工业大学；

【摘要】 蓝宝石是第三代半导体材料GaN的主要衬底材料,其表面质量直接影响器件的性能。对蓝宝石衬底片进行CMP研究,系统分析了影响CMP效果的多种因素,讨论了CMP机理模型,采用自制的小粒径（20～30nm）、低分散度的SiO₂水溶胶磨料,避免由粒径不均匀造成的划伤,在抛光过程中向CMP浆料中加入复合表面活性剂,降低了表面张力,实现了高凹凸选择性和低粗糙度。质量传递和温度成正向关系,温度愈高,传递速度越快、速率差愈大,通过控制适当的温度实现了粗糙度达亚纳米级,最佳值达到0.2nm,获得了比较完美的蓝宝石表面状态。更多还原

【Abstract】 Sapphire is the main substrate for the third generation semiconductor materials-GaN.The surface quality di- rectly affects device performance.In this paper,chemical mechanical polishing (CMP) of sapphire substrate is studied, several factors which influence the CMP quality are analyzed,and the mechanism of CMP model is discussed.Small size (20-30nm) and low dispersion silica sol is used as abrasive,which can avoid scratches caused by abrasive granules with un- even diameter.The complex surfactant of the slurry can reduce the surface tension and accelerate the mass transfer of the reactant and reaction product effectively,which can accelerate the reaction and lead to better concave-convex selectivity and low roughness.We also find that the mass transfer is related with the temperature,the higher the temperature,the faster the transmission speed.So the removal rate is higher.By controlling the polishing temperature,the roughness can reach 0.2nm and the perfect sapphire surface is achieved.更多还原