Patent ID: 7825595

Claim:
A controllable gas-discharge device, comprising an anode and a hollow cathode having a cavity and a base, the hollow cathode being separated from the anode and the base of the cathode being oriented thereto, wherein said base is provided with openings embedded therein for coupling the main discharge gap to a trigger electrode which is arranged in the cathode cavity and is provided with an igniter made of a polycrystal semiconductor material, wherein the igniter is made of polycrystal material based on a semiconductor whose energy gap is larger than 1.5, the device further comprising at least two contacting electrodes connected to the igniter, wherein at least one contacting electrode is connected to the trigger electrode, whereas the other is insulated therefrom and connected to the cathode, and wherein the maximum width of the contacting electrode in the cross-section thereof across a point where it is brought into contact with the igniter is equal to or less than 100 times the average pitch of roughness value on the igniter surface.