An electron emission element (20) includes a first electrode (30a) and a second electrode (40) which are arranged facing each other, an intermediate layer (50) that is provided between the first electrode (30a) and the second electrode (40), and an insulating layer (60) that is formed with a thickness d1 on a substrate (30). A level difference between the insulating layer (60) and the first electrode (30a) is smaller than the thickness d1 of the insulating layer (60).

An electron emission element (20) includes a first electrode (30a) and a second electrode (40) which are arranged facing each other, an intermediate layer (50) that is provided between the first electrode (30a) and the second electrode (40), and an insulating layer (60) that is formed with a thickness d1 on a substrate (30). A level difference between the insulating layer (60) and the first electrode (30a) is smaller than the thickness d1 of the insulating layer (60).

A vacuum electron tube comprises at least one electron-emitting cathode and at least one anode arranged in a vacuum chamber, the cathode having a planar structure comprising a substrate comprising a conductive material, a plurality of nanotube or nanowire elements electrically insulated from the substrate, the longitudinal axis of the nanotube or nanowire elements substantially parallel to the plane of the substrate, and at least one first connector electrically linked to at least one nanotube or nanowire element so as to be able to apply a first electrical potential to the nanowire or nanotube element.

A vacuum electron tube comprises at least one electron-emitting cathode and at least one anode arranged in a vacuum chamber, the cathode having a planar structure comprising a substrate comprising a conductive material, a plurality of nanotube or nanowire elements electrically insulated from the substrate, the longitudinal axis of the nanotube or nanowire elements substantially parallel to the plane of the substrate, and at least one first connector electrically linked to at least one nanotube or nanowire element so as to be able to apply a first electrical potential to the nanowire or nanotube element.

An electron emitting device (100) includes a first electrode (12), a second electrode (52), and a semi-conductive layer (30) provided between the first electrode (12) and the second electrode (52). The semi-conductive layer (30) includes a porous alumina layer (32) having a plurality of pores (34) and silver (42) supported in the plurality of pores (34) of the porous alumina layer (32).

An electron emitting device (100) includes a first electrode (12), a second electrode (52), and a semi-conductive layer (30) provided between the first electrode (12) and the second electrode (52). The semi-conductive layer (30) includes a porous alumina layer (32) having a plurality of pores (34) and silver (42) supported in the plurality of pores (34) of the porous alumina layer (32).

Provided in the present disclosure is an electron emitting element 10 including a laminated structure in which a first electrode 1, an electron accelerating layer 6 made of an insulation film, a second electrode 3, and a cover film 7 are laminated in that order, in which the second electrode is an electrode which transmits electrons and emits electrons from a surface thereof, and the cover film is a film which transmits electrons, is a protective film made of a material different from that of the second electrode, and constitutes an electron emission surface 5.

Provided in the present disclosure is an electron emitting element 10 including a laminated structure in which a first electrode 1, an electron accelerating layer 6 made of an insulation film, a second electrode 3, and a cover film 7 are laminated in that order, in which the second electrode is an electrode which transmits electrons and emits electrons from a surface thereof, and the cover film is a film which transmits electrons, is a protective film made of a material different from that of the second electrode, and constitutes an electron emission surface 5.

A tunneling electro source, an array thereof and methods for making the same are provided. The tunneling electron source is a surface tunneling micro electron source having a planar multi-region structure. The tunneling electron source includes an insulating substrate, and two conductive regions and one insulating region arranged on a surface of the insulating substrate. The insulating region is arranged between the two conductive regions and abuts on the two conductive regions. Minimum spacing between the two conductive regions, which equals to a minimum width of the insulating region, is less than 100 nm.

An electron emission element (20) includes a first electrode (30a) and a second electrode (40) which are arranged facing each other, an intermediate layer (50) that is provided between the first electrode (30a) and the second electrode (40), and an insulating layer (60) that is formed with a thickness d1 on a substrate (30). A level difference between the insulating layer (60) and the first electrode (30a) is smaller than the thickness d1 of the insulating layer (60).