Ran Nitride test after gas bottle change and here are the test
results; Four test wafers ran in one load.
avg. std dev. % range IR
1) 992 18.9 2.5 1.97 back
2) 1048 24.9 3.78 1.97 front tw
3) 1017 23.4 3.23 1.97 left side tw
4) 1019 24.1 3.1 1.97 right side tw