A POST METALLIZATION STRESS RELIEF ANNEALING HEAT TREATMENT FOR ARC TIN OVER ALUMINIUM LAYERS

摘要

An heat treatment (anneal) process is provided that reduces stress in a metallayer structure having ARC TiN layer overlaying an aluminum layer formed in a hightemperature process. An metal layer 32 composed of Al/Cu/Si is sputtered at a temperature ofabout 505[err]C on a semiconductor structure 10. Next, an ARC TiN layer 34 is deposited over themetal layer 32. In an important process, a heat treatment (anneal) is performed on the metal layer32 and the ARC TiN layer 34. The heat treatment comprises three steps. First, a ramp up stepis performed wherein the temperature is increased from room temperature to a temperature ofabout 450 [err]C at a rate of about 40 [err]C/sec. Second, a temperature hold step is performed wherethe temperature is held at about 450 [err]C for a time of about 30 seconds. Third, a ramp down stepis performed where the temperature is ramped down at rate in a range of between about 8 and 10[err]C /sec to room temperature. The heat treatment anneal of the present invention reduces thestress between the ARC TiN and Al layers which eliminates any peeling and blemishing of theARC TiN layer.(FIGURE 1 IS SUGGESTED FOR PUBLICATION)