In the method for producing a
plasma jet, which is extracted from a
plasma produced by electric and magnetic fields by a
high frequency voltage being applied to an extraction
electrode and an HF
electrode apparatus having an excitation
electrode with an excitation surface, a
plasma chamber being arranged between an extraction electrode and an excitation surface and, as compared with the extraction electrode, the
time average of the plasma
lying at a higher potential accelerating positive plasma ions, and the plasma and extracted
plasma jet being influenced by a
magnetic field, the invention provides that, in order to produce a
magnetic field, use is made of a
planar magnetron which is arranged after the excitation electrode on the side facing away from the plasma, and the magnetic north poles and magnetic south poles of which are directed into the interior of the
plasma chamber, so that a curved
magnetic field projecting into the interior of the
plasma chamber is formed. In the plasma source for carrying out the method, having a plasma vessel with an extraction electrode and having an HF electrode apparatus, having an excitation electrode with an excitation surface, which is or can be connected via a matching network to an HF generator, a
plasma chamber, in which a plasma can be excited, being located between excitation surface and extraction electrode, and the size of the area of the extraction electrode and of the excitation surface being chosen such that virtually all of the
high frequency voltage is dropped across the extraction electrode; having a magnetic device for reducing the magnetic field, provision is made for the magnetic device to have at least one magnetic
north pole and one magnetic south pole, which are in each case arranged after the excitation electrode on the side facing away from the plasma chamber and are directed into the interior of the plasma chamber, so that a curved magnetic field projecting into the interior of the plasma chamber can be formed, wherein at least one of the north or south poles is designed to be elongated, so that a tunnel-like region can be formed in which charged particles can be retained and along which they are able to propagate.