Methods of fabricating optimization involving process sequence analysis

A method for performing fabrication sequence analysis, the method comprising:

• defining a process group, wherein a process group includes fabrication processes in a fabrication sequence;
• determining fabrication process paths in the process group to define independent variables, wherein a process path is a plurality of fabrication equipment used to fabricate a particular semiconductor device in the fabrication sequence;
• receiving a dependent variable for the fabrication sequence;
• performing analysis of variance to calculate a p-value for the process group;
• determining whether the p-value is lower than a threshold value;
• identifying a poor process path responsive to determining that the p-value is lower than a threshold value;
• outputting the identified poor process path;
• determining whether the dependent variable is a parametric value;
• calculating Cpk values, wherein
• Cpk
• =
• min
• ⁡
• [
• USL
• -
• mean
• 3
• ⁢
• σ
• ,
• mean
• -
• LSL
• 3
• ⁢
• σ
• ]
• and USL is an upper specification limit, LSL is a lower specification limit, mean is an average value of the parametric variable for the process path, and σ is a standard deviation of the parametric variable for the process path;
• and
• identifying a process path having a lowest Cpk value as the poor process path.