JPS5738528A - Multicold electron emission cathode - Google Patents

Abstract

PURPOSE:To control a plurality of beams by forming a plurality of N type semiconductor layers which are insulated each other and connected through a plurality of orifices on the back surface of a P type semiconductor layer which serves as a common electron emission surface, and by changing the bias between both layers. CONSTITUTION:Eight N type silicon semiconductor layers 2, 2... which are insulated each other are formed on the surface of a P type or an intrinsic semiconductor, and then the surface is oxidizd to form a silicon oxide insulating layer 3. Then orifices 4, 4... are formed on the insulating layer 3 by etching method on apropriate positions which correspond to N type layers 2, 2... respectively, and it serves as an electron emisson region. Furthermore a P type silicon semiconductor layer 5 is formed on the insulating layer 3 by vapor phase growing method to serve as a common electron emission surface. A forward bias voltage is applied between the P type layer 5 and N type layers 2,2... to emit electrons through orifices 4, 4.... Thus a plurality of electron beams can be controlled independently.