蓝宝石化学机械抛光时磨粒运动轨迹及抛光效果研究

Trajectory of Abrasive Particles and Effect of Polishing in Chemical Mechanical Polishing of Sapphire

通过化学机械抛光工艺,获得表面平整度和粗糙度优良的蓝宝石晶片,提高蓝宝石键合接触面的表面性能。采用数值分析软件对蓝宝石晶片化学机械抛光过程中磨粒的运动轨迹进行仿真,结果发现,随着晶片转速的上升,磨粒的覆盖区域增大,当晶片转速与抛光盘转速接近于1∶1时,磨粒的抛光区域覆盖整个晶面。采用控制变量实验的方法研究摆臂的运动和抛光盘的转速对抛光效果的影响,并采用AFM对抛光后的蓝宝石晶片表面形貌进行分析。结果表明,抛光盘转速对抛光效果的影响最大,而移动幅度与移动速度的影响较小。通过调整晶片转速,蓝宝石晶片抛光后达到了键合工艺所要求的表面平整度和表面粗糙度要求。

Sapphire wafer can get excellent surface flatness and roughness by chemical mechanical polishing process.The trajectory equation of abrasive particles in the process of chemical mechanical polishing sapphire wafer was simulated by numerical analysis software.The results show that as the wafer speed increases,the coverage area of abrasive particles on the sapphire wafer surface is increased.When the ratio of chip speed and polishing disk rotational speed is close to 1 ∶ 1,the whole face of sapphire wafer is covered by the abrasive particles.The influence of arm swing and the speed of disc on polishing effect was studied by mesns of control variable method,and the surface morphology of sapphire chips was analyzed by AFM.The results indicate that the disc speed has the greatest influence on the polishing effect,while the movement amplitude and movement speed have less influence on the polishing effect.By adjusting the revolving speed,the surface of sapphire wafer after polishing can meet the requirements of the surface flatness and roughness required by the bonding process.