Electron emitters and methods of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

Electron emitters and method of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

Electron emitters and methods of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

The purpose of the present invention is to provide an emitter that is made of hafnium carbide (HfC) and that releases electrons in a stable and highly efficient manner, a method for manufacturing the emitter, and an electron gun and electronic device in which the emitter is used. In this nanowire equipped emitter, the nanowires are made of hafnium carbide (HfC) single crystal, the longitudinal direction of the nanowires match the <100> crystal direction of the hafnium carbide single crystal, and the end part of the nanowires through which electrons are to be released comprise the (200) face and the {310} face of the hafnium carbide single crystal, with the (200) face being the center and the {311} faces surrounding the (200) face.

Electron emitters and method of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

The purpose of the present invention is to provide an emitter that is made of hafnium carbide (Hf) and that releases electrons in a stable and highly efficient manner, a method for manufacturing the emitter, and an electron gun and electronic device in which the emitter is used.

In this nanowire-equipped emitter, the nanowires are made of hafnium carbide (HfC) single crystal, the longitudinal direction of the nanowires match the <100> crystal direction of the hafnium carbide single crystal, and the end part of the nanowires through which electrons are to be released comprise the (200) face and the {310} face of the hafnium carbide single crystal, with the (200) face being the center and the {311} face surrounding the (200) face.

Electron emitters and methods of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

The present invention provides an emitter made of a hafnium carbide (HfC) single crystal that stably emits electrons with high efficiency, a method for manufacturing the emitter, and an electron gun and an electronic device using the emitter. An emitter according to an embodiment of the present invention is an emitter including a nanowire, in which the nanowire is made of the hafnium carbide (HfC) single crystal, at least an end of the nanowire through which electrons are to be emitted is coated with hafnium oxycarbide (HfC.sub.1-xO.sub.x: 0<x?0.5), and a field electron emission pattern of the end obtained by a field emission microscope (FEM) is a single spot.

Electron emitters and methods of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

An electron source emitter is made from transition metal carbide materials, including hafnium carbide (HfC), zirconium carbide (ZrC), titanium carbide (TiC), vanadium carbide (VC), niobium carbide (NbC), and tantalum carbide (TaC), which are of high refractory nature. Preferential evaporating and subsequent development of different crystallographic planes of the transition metal carbide emitter having initially at its apex a small radius (50 nm-300 nm) develop over time an on-axis, sharp end-form or tip that is uniformly accentuated circumferentially to an extreme angular form and persists over time. An emitter manufactured to the (110) crystallographic plane and operating at high electron beam current and high temperature for about 20 hours to 40 hours results in the (110) plane, while initially not a high emission crystallographic orientation, developing into a very high field emission orientation because of the geometrical change. This geometrical change allows for a very high electric field and hence high on-axis electron emission.