A thermionic dispenser cathode having a refractory metal matrix with scandium and barium compounds in contact with the metal matrix and methods for forming the same. The invention utilizes atomic layer deposition (ALD) to form a nanoscale, uniform, conformal distribution of a scandium compound on tungsten surfaces and further utilizes in situ high pressure consolidation/impregnation to enhance impregnation of a BaOCaOAl.sub.2O.sub.3 based emissive mixture into the scandate-coated tungsten matrix or to sinter a tungsten/scandate/barium composite structure. The result is a tungsten-scandate thermionic cathode having improved emission.

An electron source capable of suppressing consumption of an electron emission material is provide. The present invention provides an electron source including: an electron emission material; and, an electron emission-suppressing material covering a side surface of the electron emission material, wherein a work function of the electron emission-suppressing material is higher than that of the electron emission material, and a thermal emissivity of the electron emission-suppressing material is lower than that of the electron emission material.

An electron source capable of suppressing consumption of an electron emission material is provide. The present invention provides an electron source including: an electron emission material; and, an electron emission-suppressing material covering a side surface of the electron emission material, wherein a work function of the electron emission-suppressing material is higher than that of the electron emission material, and a thermal emissivity of the electron emission-suppressing material is lower than that of the electron emission material.

An electrode module includes an electrode and a core wire inserted into a core wire insertion hole of the electrode. When inserting the core wire into the core wire insertion hole of the electrode, the core wire can be inserted smoothly, thereby avoiding occurrence of chipping or cracking in the core wire insertion hole. A low-friction layer is provided on the inner surface of the core wire insertion hole of the electrode and/or the outer periphery of the inserted portion of the core wire.

A thermionic cathode, an electron emission apparatus, and a method of fabricating the thermionic cathode are provided. The thermionic cathode includes an emitter. The emitter includes a lanthanum hexaboride (LaB.sub.6) crystal having a crystallographic orientation of (310). The operating temperature of the thermionic cathode is greater than 1800 K.

A thermionic cathode, an electron emission apparatus, and a method of fabricating the thermionic cathode are provided. The thermionic cathode includes an emitter. The emitter includes a lanthanum hexaboride (LaB.sub.6) crystal having a crystallographic orientation of (310). The operating temperature of the thermionic cathode is greater than 1800 K.

In the present invention, a flat emitter is formed from emitter material preforms shaped as thin sheets of the emitter material. These sheets are subjected to various levels and/or amounts of mechanical working during their initial formation and are bonded to one another to create a preform having the desired thickness. The preform including the bonded sheets is subsequently worked to shape the preform into the desired configuration for the emitter. The working of the sheets of emitter material utilized to create the preform and the working of the preform to form the emitter provide a highly creep-resistant emitter that significantly improves the operation and useful life of the resulting emitter.

In the present invention, a flat emitter is formed from emitter material preforms shaped as thin sheets of the emitter material. These sheets are subjected to various levels and/or amounts of mechanical working during their initial formation and are bonded to one another to create a preform having the desired thickness. The preform including the bonded sheets is subsequently worked to shape the preform into the desired configuration for the emitter. The working of the sheets of emitter material utilized to create the preform and the working of the preform to form the emitter provide a highly creep-resistant emitter that significantly improves the operation and useful life of the resulting emitter.

A current CMOS technology compatible process to create a planar gate-insulated vacuum channel semiconductor structure. In one example, the structure is created on highly doped silicon. In another example, the structure is created on silicon on insulator (SOI) over a box oxide layer. The planar gate-insulated vacuum channel semiconductor structure is formed over a planar complementary metal-oxide-semiconductor (CMOS) device with a gate stack and a tip-shaped SiGe source/drain region. Shallow trench isolation (STI) is used to form cavities on either side of the gate stack. The cavities are filled with dielectric material. Multiple etching techniques disclosed creates a void in a channel in the tip-shaped SiGe source/drain region under the gate stack. A vacuum is created in the void using physical vapor deposition (PVD) in a region above the tip-shaped SiGe source/drain regions.

A cathode heater assembly for use in a vacuum electronic device comprises a refractive cup having a bottom portion and side walls forming a container; a cathode secured in the container of the refractive cup; and a heater wire coupled to the refractive cup. The cathode heater assembly may be manufactured by providing a refractive cup having a bottom portion and side walls forming a container; inserting a cathode pellet in the container of the refractive cup; impregnating the cathode pellet with electron emissive materials while the cathode pellet is in the container of the refractive cup; and attaching a heater wire to the refractive cup.