Patent ID: 10844470

Abstract:
The present invention provides an epitaxial film forming method for epitaxially growing a high-quality group III nitride semiconductor thin film on an α-Al2O3 substrate by a sputtering method. In the epitaxial film forming method according to an embodiment of the present invention, when an epitaxial film of a group III nitride semiconductor thin film is to be formed on the α-Al2O3 substrate arranged on a substrate holder provided with a heater electrode and a bias electrode of a sputtering apparatus, in a state where the α-Al2O3 substrate is maintained at a predetermined temperature by the heater electrode, high-frequency power is applied to a target electrode and high-frequency bias power is applied to a bias electrode and at that time, the powers are applied so that frequency interference between the high-frequency power and the high-frequency bias power does not occur.