A plasma CVD device, - comprising: - a vacuum chamber, - a CVD electrode provided in the vacuum chamber, and - a supporting mechanism, - wherein: - the CVD electrode comprises a plasma processing electrode and a source gas nozzle configured to introduce a CVD source gas into a neighborhood of an electrode main body of the plasma processing electrode, - the plasma processing electrode comprises the electrode main body, ground members, and a gas nozzle, - the electrode main body comprises a discharge surface on an outer circumference surface thereof and a magnet provided inside configured to form a tunnel-shaped magnetic field continuously surrounding the electrode main body, when viewing the electrode main body From the supporting mechanism's side, on the discharge surface, - the electrode main body further comprises a cathode comprising the discharge surface on a surface thereof and a yoke configured to induce magnet flux generated by the magnet onto the cathode, - the ground members face at least a portion of the discharge surface with a gap therebetween and face each other so as to sandwich the electrode main body therebetween, - the discharge surface surrounds the outer circumference surface of the electrode main body, either with or without a gap interposed therebetween, when viewing the electrode main body from the supporting mechanism's side, - the gas nozzle is configured to introduce a gas in a direction parallel to the electric discharge surface into an electric discharge space between the ground member and the electric discharge surface facing the ground member, and - the supporting mechanism is configured to support a substrate placed in a position which is distant from the electrode main body and which is downstream in a flow direction of the gas discharged from the gas nozzle. - comprising: - a vacuum chamber, - a CVD electrode provided in the vacuum chamber, and - a supporting mechanism, - a vacuum chamber, - a CVD electrode provided in the vacuum chamber, and - a supporting mechanism, - wherein: - the CVD electrode comprises a plasma processing electrode and a source gas nozzle configured to introduce a CVD source gas into a neighborhood of an electrode main body of the plasma processing electrode, - the plasma processing electrode comprises the electrode main body, ground members, and a gas nozzle, - the electrode main body comprises a discharge surface on an outer circumference surface thereof and a magnet provided inside configured to form a tunnel-shaped magnetic field continuously surrounding the electrode main body, when viewing the electrode main body From the supporting mechanism's side, on the discharge surface, - the electrode main body further comprises a cathode comprising the discharge surface on a surface thereof and a yoke configured to induce magnet flux generated by the magnet onto the cathode, - the ground members face at least a portion of the discharge surface with a gap therebetween and face each other so as to sandwich the electrode main body therebetween, - the discharge surface surrounds the outer circumference surface of the electrode main body, either with or without a gap interposed therebetween, when viewing the electrode main body from the supporting mechanism's side, - the gas nozzle is configured to introduce a gas in a direction parallel to the electric discharge surface into an electric discharge space between the ground member and the electric discharge surface facing the ground member, and - the supporting mechanism is configured to support a substrate placed in a position which is distant from the electrode main body and which is downstream in a flow direction of the gas discharged from the gas nozzle. - the CVD electrode comprises a plasma processing electrode and a source gas nozzle configured to introduce a CVD source gas into a neighborhood of an electrode main body of the plasma processing electrode, - the plasma processing electrode comprises the electrode main body, ground members, and a gas nozzle, - the electrode main body comprises a discharge surface on an outer circumference surface thereof and a magnet provided inside configured to form a tunnel-shaped magnetic field continuously surrounding the electrode main body, when viewing the electrode main body From the supporting mechanism's side, on the discharge surface, - the electrode main body further comprises a cathode comprising the discharge surface on a surface thereof and a yoke configured to induce magnet flux generated by the magnet onto the cathode, - the ground members face at least a portion of the discharge surface with a gap therebetween and face each other so as to sandwich the electrode main body therebetween, - the discharge surface surrounds the outer circumference surface of the electrode main body, either with or without a gap interposed therebetween, when viewing the electrode main body from the supporting mechanism's side, - the gas nozzle is configured to introduce a gas in a direction parallel to the electric discharge surface into an electric discharge space between the ground member and the electric discharge surface facing the ground member, and - the supporting mechanism is configured to support a substrate placed in a position which is distant from the electrode main body and which is downstream in a flow direction of the gas discharged from the gas nozzle.