Tooling apparatus and methods are provided to fabricate semiconductor devices in which controlled thermal annealing techniques are utilized to modulate microstructures of metallic interconnect structures. For example, an apparatus includes a single platform semiconductor processing chamber having first and second sub-chambers. The first sub-chamber is configured to receive a semiconductor substrate comprising a metallization layer formed on a dielectric layer, wherein a portion of the metallization layer is disposed within an opening etched in the dielectric layer, and to form a stress control layer on the metallization layer. The second sub-chamber comprises a programmable hot plate which is configured to perform a thermal anneal process to modulate a microstructure of the metallization layer while the stress control layer is disposed on the metallization layer, and without an air break between the process modules of forming the stress control layer and performing the thermal anneal process.