Question

PLEASE USE R PROGRAMMING TO SOLVE THIS AND PASTE A COPYABLE CODE

Photoresist is a light-sensitive material applied to semiconductor wafers so that the circuit pattern can be imaged on to the wafer. After application, the coated wafers are baked to remove the solvent in the photoresist mixture and to harden the resist. Here are measurements of photoresist thickness (in kA) for eight wafers baked at two different temperatures. We want to see whether different temperatures make difference. The data is a text file named p1.txt.

a). read in data (copy your R code)

b). Conduct T-test

c). Copy your R output

d). Make your conclusion.

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p1.txt

T95 T100
11.176 5.263
7.089 6.748
8.097 7.461
11.739 7.015
11.291 8.133
10.759 7.418
6.467 3.772
8.315 8.963

Answer 1

The R code is as,

T95 = c (11.176, 7.089 ,8.097 ,11.739 ,11.291 ,10.759 ,6.467 ,8.315 )
T100 = c(5.263,6.748,7.461,7.015,8.133,7.418,3.772,8.963)
T95
T100
d<-as.data.frame(list(
group=c(rep("T95", 8), rep("T100", 8)),
temp=c(T95, T100)
))
print(d)

res<-t.test(temp ~ group, data=d)
res

Output of the above code is

Welch Two Sample t-test

data: temp by group
t = -2.6751, df = 13.226, p-value = 0.01885
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
-4.5515722 -0.4884278
sample estimates:
mean in group T100 mean in group T95
6.846625 9.366625

Conclusion

From the above p-value we can conclude that,

P-Value is significant(p-Valude<0.05), there is significant differeance in the tempretures.

Thanks