Investigation of NOR flash Floating Gate (FG) Residue defect improve

Floating gate (FG) residue is one of the major defects of NOR Flash products, introduction of "ox loss" concept and through the past data research "ox loss" relationship with the defect, the study found that ox loss and defect fail was significantly negative correlation, and different products have different "ox loss" threshold. Fail bin and ox loss curve has the same turning point as the above methods, show that the method can get considerable credibility of ox loss data. Further, combining with the defect and CP data can determine the appropriate ox loss control value. Based on the mechanism of defect, put forward to solve the defects of process improvement direction: adjust the STI CMP or CVT WET extend the FG CMP window. Choose one of the direction to design experiment, the results show that "STI CMP OP-" can effectively improve the FG CMP window.