The following values of saturation drain current (ID,sat) were collected from several test wafers with a sample size of n = 5.
(a) Calculate the centerlines and control limits.
(b) Assuming ID,sat to be normally distributed, compute the standard deviation of the process.
(c) Give an estimate of the fraction nonconforming if the specification limits are 1.03 ± 0.04 mA.
(d) Suggest ways to reduce the fraction of nonconforming product.