Film formation apparatus and film formation method of gallium nitride film

A film formation method of a gallium nitride film, comprising:

• placing a substrate so as to face a target containing nitride and gallium in a vacuum chamber;
• heating the substrate;
• supplying a sputtering gas to the vacuum chamber;
• supplying a nitrogen radical and a hydrogen radical to the vacuum chamber;
• applying a voltage to the target to generate a plasma of the sputtering gas;
• stopping the application of the voltage to the target;
• stopping the supply of the nitrogen radical and the hydrogen radical to the vacuum chamber;
• and
• supplying a chlorine radical to the vacuum chamber,
• wherein gallium nitride generated by a recombination reaction between the gallium sputtered from the target and the nitrogen radical, and gallium nitride generated by a recombination reaction between a gallium cation generated from the gallium of the target and a nitrogen anion generated from the nitrogen radical are deposited on the substrate, and
• wherein the gallium nitride film formed on the substrate is etched using the chlorine radical.