1. 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...

MEANS OF TWO SAMPLES (VARIANCES UNKNOWN) AND OBSERVED OBSERVATIONS

Give the complete Test of Hypothesis

Extracted text: 1. 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. The observed etch rates are as follows (in mils per minute): Do the data support the claim that the mean etch rate is the same for both solutions? In reaching your conclusions, use a=0.05 and assume that population variances are unequal. Solution 1 9.9 9.4 9.0 10.0 10.3 10.5 10.4 10.1 10.3 10.1 Solution 2 10.8 10.1 10.3 10.5 10.0 10.0 10.2 10.3 10.4 10.3