(Solved): In semiconductor manufacturing, wet chemical etching is often used to remove silicon from the backs ...

In semiconductor manufacturing, wet chemical etching is often used to remove silicon from the backs of wafers prior to metalisation. The etch rate is an important characteristic in this process and known to follow a normal distribution. Two different etching solutions have been compared, using two random samples of 10 wafers for each etch solution. The observed etch rates are as follows (in mils/min): \begin{tabular}{|c|c|} \hline Solution 1 & Solution 2 \\ \hline 9.9 & 10.2 \\ \hline 9.4 & 10.6 \\ \hline 9.3 & 10.7 \\ \hline 9.6 & 10.4 \\ \hline 10.2 & 10.5 \\ \hline 10.6 & 10.0 \\ \hline 10.3 & 10.2 \\ \hline 10.0 & 10.7 \\ \hline 10.3 & 10.4 \\ \hline 10.1 & 10.3 \\ \hline \end{tabular} For the above data set calculate the following confidence intervals: (i) \( 95 \% \) confidence interval for the population mean of Solution 2. (ii) 95\% confidence interval for the population standard deviation for Solution 2. (iii) 95\% confidence interval for the population ratio of variances (iv) 95\% confidence interval for the difference in population means For each confidence interval, interpret the result in the context of the original problem for which the data set was collected.