Ceramic-metal sealed-off pseudospark switch with a trigger unit based on flashover

Considerable interest has recently been generated in a new type of high-voltage switching device that depends on a low-pressure gas discharge with cold cathode, often called the pseudospark switch. This switch is considered as an alternative to thyratrons in facilities that require high di/dt and small jitter. The electrode system of the switch consists of an anode and a hollow cathode whose cavity communicates with the main gap through a central bore hole or several holes. The trigger unit is typically placed inside the cathode cavity. The unit is intended to provide an electron flux into the main gap and so to trigger the switch. In order that the switch be triggered in nanosecond time scale, its design should ensure easy communication between the cavity and the main gap. However, such a design causes a decrease in the static breakdown voltage of the switch. A construction with a flashover trigger unit may eliminate the above mentioned contradiction that is demonstrated in the present paper