Positioned immediately after contact formation (W CMP and post-CMP clean) and before the first metal routing (M1), this low-temperature anneal serves as a critical stabilization and passivation phase A1.During the preceding contact metallization, the deposition of titanium, titanium nitride liners, and tungsten plugs introduces substantial thermo-mechanical stress, which is further exacerbated by the shear forces of chemical-mechanical polishing (CMP) T3.The subsequent anneal is required to reli