Method of forming metal oxide using an atomic layer deposition process

A method of forming a metal oxide comprising:

• introducing a first reactant including a metal, at least one alkoxide group and at least one multidentate ligand including at least two electron pair donors into a chamber to chemisorb the first reactant onto a substrate, and to bond the alkoxide group and the multidentate ligand to the metal;
• removing a non-chemisorbed first reactant from the chamber;
• and
• introducing a second reactant into the chamber to form the metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the alkoxide group and the multidentate ligand from the metal,
• wherein the first reactant is represented by the following chemical formula,
• wherein, M represents the metal, and R1 to R6 independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.