阅读说明：本技术 一种通过激光加工阴极发射体单尖锥的方法 (Method for machining single pointed cone of cathode emitter through laser ) 是由 张伟 张晓兵 蔡敏 李元成 纪亮 焦佳能 于 2019-11-19 设计创作，主要内容包括：本发明提供的一种通过激光加工阴极发射体单尖锥的方法,包括以下步骤：(1)激光光束经聚焦镜聚焦后,形成聚焦光束；(2)将阴极发射体安装到可旋转运动装置上；(3)阴极发射体和可旋转运动装置沿同一旋转轴进行旋转运动；(4)聚焦光束中心线与旋转运动中的阴极发射体呈一定角度移动靠近并在聚焦光束焦点处接触,利用激光去除阴极发射体材料,实现阴极发射体单尖锥加工。本发明的方法与湿腐蚀法、高温氧作用离子腐蚀法、电化学腐蚀法相比,可以同时实现对钨、锆、金属氧化物和六硼化镧等场发射阴极发射体单尖锥的高效加工,并且曲率半径可控、加工过程无污染。(The invention provides a method for processing a cathode emitter single pointed cone by laser, which comprises the following steps: (1) the laser beam is focused by the focusing lens to form a focused beam; (2) mounting a cathode emitter to a rotatable motion device; (3) the cathode emitter and the rotary motion device rotate along the same rotating shaft; (4) the central line of the focusing beam and the cathode emitter in rotary motion move close to each other at a certain angle and contact each other at the focus of the focusing beam, and the cathode emitter material is removed by laser to realize the processing of the single-pointed cone of the cathode emitter. Compared with a wet corrosion method, a high-temperature oxygen action ion corrosion method and an electrochemical corrosion method, the method can simultaneously realize the high-efficiency processing of the single pointed cone of the field emission cathode emitter such as tungsten, zirconium, metal oxide, lanthanum hexaboride and the like, and has the advantages of controllable curvature radius and no pollution in the processing process.)

1. A method of machining a single pointed cone of a cathode emitter by laser, comprising the steps of:

(1) the laser beam (1) is focused by the focusing lens (2) to form a focused beam (3);

(2) mounting the cathode emitter (4) on a rotatable movement means (5);

(3) the cathode emitter (4) and the rotatable movement device (5) perform rotary movement along the same rotary shaft (6);

(4) the central line of the focused light beam (3) and the cathode emitter (4) in rotary motion move to approach at a certain angle and contact at the focus of the focused light beam (3), and the cathode emitter material is removed by laser to realize the processing of the cathode emitter single-tip cone.

2. The method of claim 1, wherein the laser beam (1) has a pulse width of 100 ns or less and a wavelength of 1064 nm or less.

3. The method for machining the cathode emitter single pointed cone by the laser as claimed in claim 1, wherein in the step (1), the focusing lens (2) comprises a focusing objective lens and a focusing lens, and the focal length f is more than or equal to 10 mm.

4. The method of claim 1, wherein the cathode emitter (4) is made of a cathode material selected from the group consisting of tungsten, zirconium, metal oxides, and lanthanum hexaboride.

5. A method for machining a cathode emitter monoclinic cone by laser according to claim 3, characterized in that the rotatable movement means (5) can realize a stable 360 ° rotation along the rotation axis (6) at a rotation rate of 10r/min or more.

6. The method for machining a single pointed cone of a cathode emitter by laser as claimed in claim 1, wherein in the step (4), the angle formed by the central line of the focused light beam (3) and the cathode emitter (4) in the rotary motion is realized by rotating the rotary motion device (5) along the axis perpendicular to the paper surface.

7. The method for machining the cathode emitter single pointed cone by the laser as claimed in claim 1, characterized in that, in the step (4), the certain angle between the central line of the focused light beam (3) and the cathode emitter (4) in the rotary motion is realized by rotating the focused light beam (3) along the axis perpendicular to the paper surface.

Technical Field

The invention belongs to the technical field of material processing, and particularly relates to a method for processing a cathode emitter single pointed cone by laser.

Background

The single pointed cone cathode emitter is a common field emission cathode and is applied to a scanning electron microscope, an electron beam lithography system, an electron beam exposure system and the like. In order to obtain a strong field, the most common method is to process the cathode emitter into a pointed cone structure, and the curvature radius of the pointed end of the pointed cone of the cathode emitter is in a submicron order so as to reduce the working voltage of the cathode. The existing single-pointed-cone cathode emitter material comprises tungsten, zirconium, metal oxide, carbon fiber, lanthanum hexaboride and the like, and the processing method of the single-pointed-cone cathode emitter mainly comprises a wet corrosion method, a high-temperature oxygen action ion corrosion method and an electrochemical corrosion method, but has certain limitations in the aspects of environmental protection of the processing process, processing efficiency, processing control of the curvature radius of the pointed end of the pointed cone and the like. For example, although the electrochemical etching method can produce a single pointed cone cathode emitter having a small radius of curvature and a good surface finish, it requires several hours of electrochemical etching time, is inefficient, and is environmentally less friendly in the manufacturing process, compared to other methods.

Disclosure of Invention

(1) Technical problem to be solved

In view of the defects in the prior art, aiming at the requirement of a field emission cathode emitter for processing a single pointed cone, the invention provides a method for processing the single pointed cone of the cathode emitter by laser, which can simultaneously realize the high-efficiency processing of the single pointed cone of the field emission cathode emitter such as tungsten, zirconium, metal oxide, lanthanum hexaboride and the like, and has controllable curvature radius and no pollution in the processing process.

(2) Technical scheme

A method of machining a single pointed cone of a cathode emitter by laser, comprising the steps of:

(1) the laser beam 1 is focused by the focusing lens 2 to form a focused beam 3;

(2) mounting the cathode emitter 4 on a rotatable movement means 5;

(3) the cathode emitter 4 and the rotatable movement means 5 perform a rotational movement along the same rotational axis 6;

(4) the central line of the focused light beam 3 and the cathode emitter 4 in rotary motion move close to each other at a certain angle and contact with each other at the focus of the focused light beam 3, and the cathode emitter material is removed by laser to realize the processing of the single-tip cone of the cathode emitter.

Furthermore, the pulse width of the laser beam 1 is less than or equal to 100 nanoseconds (ns), and the wavelength is less than or equal to 1064 nanometers (nm).

Further, in the step (1), the focusing lens 2 includes a focusing objective lens and a focusing lens, and the focal length f is greater than or equal to 10 mm.

Further, the cathode material used for the cathode emitter 4 includes tungsten, zirconium, metal oxide, and lanthanum hexaboride.

Furthermore, the rotatable movement device 5 can realize the stable 360-degree rotation along the rotating shaft 6, and the rotation speed is more than or equal to 10 r/min.

Further, in the step (4), the angle formed by the central line of the focused light beam 3 and the cathode emitter 4 in the rotating motion is realized by rotating the rotatable moving device 5 along the axis perpendicular to the paper surface.

Further, in the step (4), the central line of the focused light beam 3 forms a certain angle with the cathode emitter 4 in the rotating motion by rotating the focused light beam 3 along the axis perpendicular to the paper surface.

According to the technical scheme, the beneficial effects of the invention are as follows:

the method for processing the cathode emitter single pointed cone by the laser is characterized in that a central axis of a focused laser beam forms a certain angle with a cathode emitter in rotary motion and is contacted with the focal point of the focused laser beam, the cathode emitter single pointed cone is processed after the cathode emitter material is removed by the laser, and the curvature radius of the cathode emitter is controlled by adjusting the angle formed by the focused laser beam and the cathode emitter in rotary motion in the processing process. Compared with a wet corrosion method, a high-temperature oxygen action ion corrosion method and an electrochemical corrosion method, the method can simultaneously realize the high-efficiency processing of the single pointed cone of the field emission cathode emitter such as tungsten, zirconium, metal oxide, lanthanum hexaboride and the like, and has the advantages of controllable curvature radius and no pollution in the processing process.

Drawings

FIG. 1 is a schematic diagram of a method for laser processing a cathode emitter single-tip cone, which realizes the adjustment of the angle formed by the cathode emitter and the central axis of a light-gathering beam by adjusting a rotating device, wherein the laser beam-1, a focusing mirror-2, a focusing beam-3, a cathode emitter-4, a rotatable moving device-5 and a rotating shaft-6.

FIG. 2 is a schematic diagram of a method for laser processing a cathode emitter single pointed cone, which adjusts the angle formed between the central axis and the cathode emitter rotation axis by adjusting the rotation of the focused light beam, wherein the laser beam-1, the focusing mirror-2, the focused light beam-3, the cathode emitter-4, the rotary motion device-5, and the rotation axis-6.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the invention and are not intended to limit the scope of the invention, i.e., the invention is not limited to the embodiments described, but covers any modifications, alterations, and improvements in the parts, components, and connections without departing from the spirit of the invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.