A surface discharge device performing functions of a trigger and electron beam generator includes a cylinder shaped member formed from a dielectric material with dielectric constant .epsilon.>100, in which a central opening is formed having a conical or cylindrical shape. An internal electrode is electrically coupled to the internal surface of the cylinder shaped member. An external electrode covers the external surface of the cylinder shaped member. A triggering pulse is applied between the external and internal electrodes to generate emission of electrons in the central opening and formation of the conducting plasma to ignite the device and serve as a source of electrons for generating an electron beam. The conducting plasma charges a capacitor formed by the cylinder shaped dielectric member and the external electrode. The cylinder shaped member is positioned in a hollow cathode having a central bore hole in the bottom. An anode is positioned remotely from the cathode and an electric field exists dynamically in space between the cathode and anode for at least a portion of the duration of the triggering pulse.