Stabilized emission from micro-field emitter for electron microscopy

Micro-fabricated field emitter for the application in miniaturized scanning electron microscope (MSEM) was fabricated on silicon substrate. Field emission studies of the micro-fabricated field emitter were carried out in an ultra high vacuum system. A simple voltage controlled feedback circuit was designed and used to regulate the gate voltage in order to improve the emission current stability of the micro-fabricated field emitter. Preliminary results showed that the emission current fluctuation ((Imax − Imin)/Iave) was reduced from 80% without feedback current stabilizer to less than 1% with the circuit control.