多片干法蚀刻设备蚀刻均匀性工艺优化研究

Optimization of Etching Uniformity for Multi-Wafer Dry Etch Equipment

对于制造集成电路芯片的多片生产设备而言,圆片间均匀性是评价工艺优劣的重要指标,可以利用正交试验方法来优化均匀性工艺。使用装载容量为18个150mm圆片的AME8110干法蚀刻设备,利用正交试验方法进行干法蚀刻二氧化硅试验。通过直观分析,得到影响干法蚀刻均匀性的较优因素组合;通过方差分析,得到各因素对均匀性影响的显著性和可信度;通过工艺综合分析,得到各因素水平的选择原则和满足圆片间均匀性指标要求的优化工艺。按照优化工艺测试的圆片间蚀刻均匀性为3.93%。正交试验分析方法同样适用于其他多片生产设备和单片生产设备的工艺优化。

Wafer-to-wafer uniformity is a key parameter to evaluate processing quality of multi-wafer production equipment in IC manufacturing process. Using orthogonal test method, experiments of SiO2 etching were made on a dry etch machine with a capacity of 18 pieces of 150-mm wafers. Better combination of factors affecting wafer-to- wafer uniformity of dry-etch process was obtained by intuitive analysis. Significance and credibility of effects of factors on wafer-to-wafer uniformity were obtained by analysis of variance： Principles to select levels of factors and optimized process conditions for targeted wafer-to-wafer uniformity in dry etch process were obtained by comprehensive technology analysis. Wafer-to-wafer uniformity using optimized process was measured to be 3. 93%. The orthogonal test and analysis method are also applicable for process optimization of other multi-wafer and single wafer production equipments.