Channel crack Low-k dielectric Copper (OSG) interconnect line KFAB1.0kV4.4mm×15.0ksEU)5/19/2000 3.00um Channel cracking,a fracture mode in which through-film cracks propagate in the film due to a tensile residual stress OGS:organosilicate glass The above picture is of a new pressure vessel that failed during its hydraulic test.The vessel had been stress relieved,but some parts of it did not reach the required temperature and consequently did not experience adequate tempering.This coupled with a small hydrogen crack,was sufficient to cause catastrophic failure under test conditions.It is therefore important when considering PWHT or its avoidance,to ensure that all possible failure modes and their consequences are carefully considered before any action is taken 33 Channel cracking, a fracture mode in which through-film cracks propagate in the film due to a tensile residual stress OGS: organosilicate glass The above picture is of a new pressure vessel that failed during its hydraulic test. The vessel had been stress relieved, but some parts of it did not reach the required temperature and consequently did not experience adequate tempering. This coupled with a small hydrogen crack, was sufficient to cause catastrophic failure under test conditions. It is therefore important when considering PWHT or its avoidance, to ensure that all possible failure modes and their consequences are carefully considered before any action is taken