My 1st wafer finished with no mishaps, but the 2nd identical wafer shattered in less than 1hr while using holder. Not sure if it is related to helium cooling. Helium pressure was 3.5-4.5 before wafer broke. Wafer is thick type with DEEP recipe.
I cannot see pieces in the o-ring area, but helium cooling pressure with my dummy wafer now reads negative. Some pieces are visible outside the chuck area.
My sincere apologies...
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