SiO2 thin film creation in Diffusion furnace - Process Functional Modeling
Current situation
The thickness standard deviation (sigma) of SiO2 thin layer on the silicon wafer is high
Disadvantages
The high standard deviation of the SiO2 thin layer on the silicon wafer is bad because it indicates that the layer is not uniform and that there are significant variations in the thickness across the wafer. This can lead to issues with the performance of the device and potential reliability issues.
Ideal final result
Use Process Functional Modeling (PFM) to create a model of the process and a model of the failure. Generate a solution
Gaps
We do not understand the reason for the different processes in the different zones
Problem statement
The process conditions are different in the different zones of the furnace. Wafers in the low zone show worse performance.
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