Thin film transistors having alloying source or drain metals are described. In an example, an integrated circuit structure includes a semiconducting oxide material over a gate electrode. A pair of conductive contacts is on a first region of the semiconducting oxide material. A second region of the semiconducting oxide material is between the pair of conductive contacts. The pair of conductive contacts includes a metal species. The metal species is in the first region of the semiconducting oxide material but not in the second region of the semiconducting oxide material.