300mm硅片精密化学机械抛光机几何参数优化(英文)

On the Improvement of Prime Silicon Wafer Geometry with 300 mm Final-touch Polishing Machine

对于评价用于极大规模集成电路(ULSI)生产的300 mm硅抛光片的表面质量,需要关注两个关键参数即:SFQR和GBIR。在中国电子科技集团第四十五研究所研发的中国第一台最终化学精密抛光机的验证过程中,我们发现为了提高硅片表面的几何参数,必须监控抛光前硅片的形貌,并根据不同的硅片表面形貌来改变抛光头的区域压力。通过深入分析抛光前硅片的表面形貌,我们发现当硅片形貌为凹陷形状时,抛光后的硅片表面将严重恶化。由此,根据每个硅片不同的形貌,我们用特殊设计的抛光头来调整背压的区域分布,然后再进行抛光。最终,经过抛光头区域压力调整后的硅片几何参数比调整前得到了大幅提升,并已经能够满足我们的产品指标并可以用于生产。

For the advanced Ultra-large Scale Integrated Circuits geometry parameters of the 300 mm prime silicon wafers： SRQR and manufacturers. During the acceptance tests of the first China-made （ULSI） manufacturing, two key GBIR are of major interest to the final-touch chemical-mechanical machine （CMP）. We find that to enhance the geometry parameters, we have to know the geometry of incoming wafers and to modify the polishing head pressure accordingly. After investigation of the geometry of the incoming wafers, we find wafers with concave thickness profile would be deteriorated seriously after final-touch CMP. According to the shape of every wafer, we vary the backing pressure distribution of our special designed polishing head. Eventually, the wafer thickness geometry after modification could fulfill our demand, which demonstrates that our own-made machine could be used in mass production.