Lifetime of ferroelectric Pb(Zr,Ti)O₃ ceramic cathodes with high current density

Electron emission from ferroelectric cathodes is investigated, it is commonly suggested as an electron source for different applications due to its special characteristics such as high current density, easy treatment, and operation. In this experimental research, a lifetime of lead zirconate-titanate ceramic cathode with composition related to a ferroelectric phase was studied. The strong plasma emission from the cathode was excited in a nonreversal (nonswitching) mode by application of unipolar high stress. Severe damage to the cathodes was observed, especially in a high repetition rate. An upper limit of the lifetime of the ferroelectric cathode with plasma-induced emission was estimated at about ∼10⁶ pulses of ∼200 ns each at ∼100 Hz repetition rate. Possible applications of the limited lifetime ferroelectric cathode are discussed.