(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 metalization. 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 solution. Assume the variances are equal. The etch rates are as follows (in mils per minute): (a) Calculate the sample mean for solution 1: \( \bar{x}_{1}= \) Round your answer to two decimal places (e.g. 98.76). (b) Calculate the sample standard deviation for solution 1: \( s_{1}= \) Round your answer to three decimal places (e.g. \( 98.765 \) ). (c) Calculate the sample mean for solution \( 2: \bar{x}_{2}= \) Round your answer to two decimal places (eg. 98.76). (d) Calculate the sample standard deviation for solution 2: \( s_{1}= \) Round your answer to three decimal places (e.g. 98.765). (e) Test the hypothesis \( H_{0}: \mu_{1}=\mu_{2} \) vs \( H_{1}: \mu_{1} \neq \mu_{2} \).
(f) Do the data support the claim that the mean etch rate is different for the two solutions? Use \( \alpha=0.05 \). (g) Calculate a \( 95 \% \) two-sided confidence interval on the difference in mean etch rate. (Calculate using the following order: \( \bar{x}_{1}-\bar{x}_{2} \) ) 1 \( \leq \mu_{1}-\mu_{2} \leq \) ) Round your answersto three decimal places (e.g. \( 98.765) \)