3.
Production
Process Characterization
3.5. Case Studies 3.5.1. Furnace Case Study


The next part of the analysis is to break down the sources of variation.  
Box Plot by Run  The following is a box plot of the thickness by run number.  
Conclusions From Box Plot 
We can make the following conclusions from this box plot.


Box Plot by Furnace Location  The following is a box plot of the thickness by furnace location.  
Conclusions From Box Plot 
We can make the following conclusions from this box plot.


Box Plot by Wafer  The following is a box plot of the thickness by wafer.  
Conclusion From Box Plot  From this box plot, we conclude that wafer does not seem to be a significant factor.  
Block Plot 
In order to show the combined effects of run, furnace location, and
wafer, we draw a block
plot of the thickness. Note that for aesthetic reasons, we have
used connecting lines rather than enclosing boxes.


Conclusions From Block Plot 
We can draw the following conclusions from this block plot.
