A kind of production method of cold cathode and cold cathode head for magnetron

Abstract

The invention belongs to the production method of a cold cathode for a magnetron and a cold cathode head. The cold cathode includes upper and lower shielding caps, a power connection rod and an integral cylindrical tooth-shaped cold cathode head; the method includes material preparation, ball milling, compacting and forming. In this invention, graphene or / and carbon nanotubes, zinc oxide nanowires, and metal powder are mixed and crushed, sintered, and processed into a column-tooth-shaped integral cold cathode head, which emits primary electrons under high voltage. The back-bombardment of primary electrons excites the gear teeth to emit secondary electrons, reciprocating to form stable electron emission, and it only takes 40 nanoseconds to reach a stable output. Thus compared with hot cathodes, it not only retains the advantages of hot cathodes such as electron emission capability and anti-electron bombardment ability, but also overcomes the disadvantages of long warm-up time, slow start-up, and short service life; compared with cold cathodes described in the background technology It has the characteristics of simple structure, strong ability to emit electrons and anti-electron bombardment, pure output spectrum, fast and stable emission speed, etc.

Description

technical field [0001] The invention belongs to the technical field of microwave device production, in particular to a production method of a cold cathode and a cold cathode head matched with a magnetron. The magnetron adopting the cold cathode emission system of the invention has better field emission capability and fast The function of exciting the magnetron is especially suitable as a microwave source for microwave application equipment including domestic microwave ovens. Background technique [0002] Magnetron is one of the most widely used electronic vacuum tubes. Because of its advantages of high efficiency, high power, small size, low working voltage and convenient use, it is a high power source in microwave technology. Magnetrons are generally used in various microwave heating devices. After years of research and exploration, the design and production of magnetrons are becoming more and more mature. Mass production can further reduce the cost of the magnetron and gr...

AI Technical Summary

Problems solved by technology

In the article "Thin Film Field Emission Cold Cathode" (see "Optoelectronics Technology" 1989, No. 04, author: Chen Lifang et al.), a microelectronic source using a three-sandwich structure cold cathode is disclosed. The microelectronic source has room temperature work, no cathode power consumption, no warm-up delay, etc., but it uses a planar emission structure, needs to add a gate, and the emission current is small, and cannot provide secondary electron emission

However, the carbon nanotube cold cathode disclosed in the patent document with the application number CN201510675065.0 and the invention titled "A Microwave-modulated Cold Cathode Micro-Array Radiation Source and Its Realization Method" also adopts a planar emission structure and cannot provide two Sub-electron emission, not suitable for use in magnetrons

[0004] In the patent document with the application number 2016101968038 and titled "Production Method of Magnetron Using Combined Cold Cathode Head and Cold Cathode Body", the applicant discloses an upper and lower shielding cap made of graphene and carbon nanotubes. A cold cathode body made by mixing one or more of zinc oxide nanowires with metal powder, and a tungsten or tungsten alloy electrode wound on the cylindrical surface of the cold cathode body as both an input electrode and a secondary electron emitter wire, wherein the cold cathode body and the electrode wire form a combined cold cathode head, although the cold cathode head has the advantages of providing both primary electron emission and secondary electron emission; but because the surface of the cold cathode body is a cylinder The surface does not have the function of secondary electron emission, and electrode wire must be used as the secondary electron emitter, so there are defects such as complex structure and long start-up time.

[0005] In addition, the electrons initially emitted by both the traditional hot cathode and the cold cathode described in the background art are disordered and scattered (see attached Figure 5 The dark ring in the middle part), after the magnetron oscillates, the gathered electron column emits. The time for the traditional hot cathode to reach a stable output is 135 nanoseconds (excluding the warm-up time), while the background technology The above-mentioned cold cathode reaches a stable output time of 80 nanoseconds, so there is a disadvantage of slow emission speed

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