# Question: A 2 4 1 design has been used to investigate the

A 2 4-1 design has been used to investigate the effect of four factors on the resistivity of a silicon wafer. The data from this experiment are shown in Table 13E.4.

Enter the factor levels and resist data into a Minitab worksheet, including a column indicating whether a run is a center point run (1 = not center point, 0 = center point). Then define the experiment using Stat > DOE > Factorial > Define Custom Factorial Design. The design and data are in the Minitab worksheet Ex13-17.MTW.

(a) Estimate the factor effects. Plot the effect estimates on a normal probability scale.

(b) Identify a tentative model for this process. Fit the model and test for curvature.

(c) Plot the residuals from the model in part (b) versus the predicted resistivity. Is there any indication on this plot of model inadequacy?

(d) Construct a normal probability plot of the residuals. Is there any reason to doubt the validity of the normality assumption?

Enter the factor levels and resist data into a Minitab worksheet, including a column indicating whether a run is a center point run (1 = not center point, 0 = center point). Then define the experiment using Stat > DOE > Factorial > Define Custom Factorial Design. The design and data are in the Minitab worksheet Ex13-17.MTW.

(a) Estimate the factor effects. Plot the effect estimates on a normal probability scale.

(b) Identify a tentative model for this process. Fit the model and test for curvature.

(c) Plot the residuals from the model in part (b) versus the predicted resistivity. Is there any indication on this plot of model inadequacy?

(d) Construct a normal probability plot of the residuals. Is there any reason to doubt the validity of the normality assumption?

## Relevant Questions

A nickel-titanium alloy is used to make components for jet turbine aircraft engines. Cracking is a potentially serious problem in the final part because it can lead to non-recoverable failure. A test is run at the parts ...An article in Quality Progress describes the use of factorial experiments to improve a silver powder production process. This product is used in conductive pastes to manufacture a wide variety of products ranging from ...The data in Table 14E.6 were collected by a chemical engineer. The response y is filtration time, x1 is temperature and x2 is pressure. Fit a second-order model. (a) What operating conditions would you recommend if the ...Consider the response model in equation 14.5. Suppose that in the response model we allow for a complete second-order model in the noise factors so that What effect does this have on the variance model? Consider the single-sampling plan found in Exercise 15.8. Suppose that lots of N = 2,000 are submitted. Draw the ATI curve for this plan. Draw the AOQ curve and find the AOQL.Post your question