Embodiments of the disclosure generally provide methods of forming thin film transistor (TFT) device structure with good interface management between active layers of a metal electrode layer and/or source/drain electrode layers and a nearby insulating material so as to provide high electrical performance devices, or for other suitable display applications. In one embodiment, a thin film transistor structure includes a contact region formed between fluorine-doped source and drain regions disposed on a substrate, a gate insulating layer disposed on the contact region, and a metal electrode layer disposed on the gate insulator layer.