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

## Work This Example Yourself

View Dataplot Macro for this Case Study This page allows you to repeat the analysis outlined in the case study description on the previous page using Dataplot, if you have downloaded and installed it. Output from each analysis step below will be displayed in one or more of the Dataplot windows. The four main windows are the Output window, the Graphics window, the Command History window and the Data Sheet window. Across the top of the main windows there are menus for executing Dataplot commands. Across the bottom is a command entry window where commands can be typed in.
Data Analysis Steps Results and Conclusions

Click on the links below to start Dataplot and run this case study yourself. Each step may use results from previous steps, so please be patient. Wait until the software verifies that the current step is complete before clicking on the next step.

The links in this column will connect you with more detailed information about each analysis step from the case study description.

```1. Get set up and started.
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```   1. Read in the data.

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``` 1. You have read 4 columns of numbers
into Dataplot, variables run, zone,
wafer, and filmthic.
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```2. Analyze the response variable.
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```   1. Normal probability plot,
box plot, and histogram of
film thickness.

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```   2. Compute summary statistics
and quantiles of film
thickness.

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```   3. Perform a capability analysis.

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``` 1. Initial plots indicate that the
film thickness is reasonably
approximated by a normal
distribution with no significant
outliers.

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``` 2. Mean is 563.04 and standard
deviation is 25.38.  Data range
from 487 to 634.

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``` 3. Capability analysis indicates
that the process is capable.

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```3. Identify Sources of Variation.
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```   1. Generate a box plot by run.

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```   2. Generate a box plot by furnace
location.

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```   3. Generate a box plot by wafer.

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```   4. Generate a block plot.

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``` 1. The box plot shows significant
variation both between runs and
within runs.

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``` 2. The box plot shows significant
variation within furnace location
but not between furnace location.

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``` 3. The box plot shows no significant
effect for wafer.

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``` 4. The block plot shows both run
and furnace location are
significant.

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```4. Perform an Analysis of Variance
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```   1. Perform the analysis of
variance and compute the
components of variance.

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``` 1. The results of the ANOVA are
summarized in an ANOVA table
and a components of variance
table.

```