A study of reducing defect by using dynamic developing method
With the mounting pressure of introducing product into market, using advanced processing technology for lowering design cost and increasing profit, the process yield is a crucial factor as IC industry enters deep sub-micron and nano processes. Therefore, how to effectively reduce the defect density generated in the lithography process and the precision control of the pattern in component critical dimension are equally important as the overlaying of different layers in. This thesis mainly focuses on the investigation of defects generated in the semiconductor developing process. Through the analysis of the cause of defects generated, the dynamic developing method is used, as opposed to the static developing method normally used, for the improvement of developing defects often seen in the process. During the developing process, the puddle developing is mainly for the reducing of micro bubbles, resulting in the graphical developing defects such as pattern bridging and missing contact hole, etc. During the DI water rinsing of developing process, the cleaning efficiency is increased to remove the developing solution and the photo-resist residues on the wafer and sticking back contamination. The experimental data shows that the number of defect die of wafer was lowered from the average 13.7 to 3.6 which is the 70% improved effect after the dynamic puddle development instead of the static puddle development. Moreover, the number of the particle on the wafer and sticking back contamination after developing was reduced from the average 45 to 26 which is the 42% improved effect after the dynamic rinse instead of the static rinse.