U.S. Philips Corporation

Petrus A Van Der Heide

Jacobus A Deckers

Franciscus M Snijkers

Albert Manenschijn

Theodorus H Weekers

Gerardus G Van Gorkom

Arthur M Hoeberechts

Aart A Van Gorkum

Gerjan F Van De Walle

A method of manufacturing a dispenser cathode, in which method a powder of a refractory metal and a scandium-containing powder are mixed with each other and pressed to form a cathode body. According to the invention at least both these powders and a suitable binder are mixed with each other to form a homogeneous suspension prior to the pressing operation and the whole mixture is subsequently cured and ground to granules having a larger average size and hence a greater fluidity than the grains of the starting powders. Subsequently the granules thus obtained are pressed to form a cathode body (2). The invention leads to a better processibility and greater convenience of handling of the starting powders so that notably very fine staring powders can be used, which results in cathodes (1) having a better recovery after ion bombardment as compared with cathodes manufactured in conventional manners which are necessarily based on relatively coarse powders.

Method of manufacturing a dispenser cathode

A method of manufacturing a dispenser cathode, in which method a powder of a refractory metal and a scandium-containing powder are mixed with each other and pressed to form a cathode body. According to the invention at least both these powders and a suitable binder are mixed with each other to form a homogeneous suspension prior to the pressing operation and the whole mixture is subsequently cured and ground to granules having a larger average size and hence a greater fluidity than the grains of the starting powders. Subsequently the granules thus obtained are pressed to form a cathode body (2). The invention leads to a better processibility and greater convenience of handling of the starting powders so that notably very fine starting powders can be used, which results in cathodes (1) having a better recovery after ion bombardment as compared with cathodes manufactured in conventional manners which are necessarily based on relatively coarse powders.

Dispenser cathode and method of manufacturing a dispenser cathode

The efficiency of semiconductor cathodes based on avalanche breakdown is enhanced by using '.delta.-doping' structures. The quantization effects introduced thereby decrease the effective work function. A typical cathode structure has an n-type semiconductor region and a first p-type semiconductor region, with the n-type region having a thickness of at most 4 nanometers.

Semiconductor device for generating an electron current

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Eindhoven, Netherlands

Petrus A Van Der Heide