A film forming apparatus for forming a metal film, comprising:
- an anode;
- a solid electrolyte membrane disposed between the anode and a substrate that serves as a cathode;
- a power supply configured to apply a voltage across the anode and the substrate;
- a housing including a storing chamber that stores an electrolytic solution together with the anode and having the solid electrolyte membrane attached thereto so as to seal the storing chamber;
- and
- a mount base on which the substrate is placed, the mount base being disposed to face the housing,
- wherein
- the voltage is applied in a state where the solid electrolyte membrane is pressed against a surface of the substrate with a fluid pressure of the electrolytic solution in the storing chamber to form a metal film from metal ions contained in the electrolytic solution on a surface of the substrate,
- a space where the metal film exists is sealed between the housing and the mount base in a state where the solid electrolyte membrane is in contact with the metal film, and
- the film forming apparatus further comprises:
- a water supply unit comprising a pressure pump in communication with a water supply groove, configured to supply a wash water to the space being sealed such that the wash water flows onto a surface of the metal film that is in contact with the solid electrolyte membrane;
- and
- a water discharge unit comprising a suction pump in communication with a water discharge groove configured to discharge a wash water from the space being sealed such that the wash water having flowed onto the surface of the metal film flows out from the surface of the metal film,
- the housing is disposed above the mount base,
- the mount base includes a housing recess that houses the substrate,
- wherein the water supply groove is on a surface of the mount base,
- wherein the water discharge groove is on a surface of the mount base,
- the water supply groove and the water discharge groove are formed in opposite positions with the housing recess interposed therebetween,
- a frame-like sealing member for sealing the space is disposed on an edge of the mount base so as to surround the water supply groove, the water discharge groove, and the housing recess,
- the film forming apparatus further comprises:
- a liquid discharge mechanism comprising a communication passage through the housing configured to discharge an electrolytic solution from the storing chamber;
- and
- a control device configured to control at least discharge of the electrolytic solution by the liquid discharge mechanism and supply of the wash water by the water supply unit, and
- the control device causes the liquid discharge mechanism to discharge the electrolytic solution in the storing chamber such that a pressing force of the solid electrolyte membrane pressing the substrate decreases, and causes the water supply unit to supply the wash water such that the solid electrolyte membrane deforms so as to be separated from the surface of the substrate and such that the wash water is poured between the solid electrolyte membrane and the metal film.