Electron emission from ferroelectric thin film cathodes

Summary form only given. The use of thin film ferroelectric materials as electron emission cathodes has been investigated. For commonly proposed applications of these materials, such as flat panel displays, electron emission currents higher than 10 s of mA/cm/sup 2/ will be required. Strong pulsed electron emission from bulk ferroelectric cathodes has been widely reported (100 s of A/cm/sup 2/), but some preliminary experiments on thin film ferroelectric cathodes showed that only relatively small currents (/spl sim/0.1 mu A/cm/sup 2/) are obtainable when the thickness is reduced to a few microns. Because of the attractive advantages of thin film cathodes in flexibility and low switching voltage, we are studying ways to improve the emission performance. Four kinds of ferroelectric thin films have been made by the sol-gel method. They are Pb0.93La0.07(Zr/sub 0.53/Ti/sub 0.47/)03 (PLZT) (Zr0.95Ti0.05)03 (PLZT), Pb(Zr0.65Ti0.35)03 (PZT), and Pb(Zr0.53Ti0.47)03 (PZT), and approximately 1 mum. Each of these stoichiometries is commonly used so our results will be comparable to previous reports.