The disclosed technology generally relates to integrated circuit devices and methods of forming the same, and more particularly to metal electrodes whose effective work function can be tuned. In one aspect, a method of forming a metal electrode of a semiconductor structure includes providing a semiconductor substrate having at least a region covered with a dielectric. The semiconductor substrate is introduced into a chamber configured for atomic layer deposition (ALD). A metal for the metal electrode is deposited at least on the dielectric by performing an ALD cycle. Performing the ALD cycle includes pulsing a Ti-containing precursor gas followed by pulsing a Ta-containing precursor gas, and further includes pulsing NH3 gas.