JPS62107099A - Method and apparatus for forming needle-like member - Google Patents

Abstract

PURPOSE:To form a needle-like member having a desired shape with good reproducibility and controllability by irradiating light to a member to be etched and monitoring an etching condition in the stage of etching the member to be etched to the needle-like member. CONSTITUTION:The light 9 is irradiated from a light source 7 to an emitter material 3 in an electrolytic cell 1 and while the light transmitted therethrough is detected by a photodetector 8, a prescribed positive voltage is impressed from a power source 6 to the material 3 to start electrolytic polishing. The intensity of the transmitted light detected by the detector 8 increases when the top end of the material 3 begins to be sharpened as shown by an alternate long and short dash line on progression of the electrolytic polishing. A control device 10 is operated to drop the output voltage of the power source 6 to the ground voltage to end the electrolytic polishing when the intensity of the transmitted light attains a prescribed value or the intensity of the transmitted light shows a specified change. The detection of the end point of etching is thereby easily detected and the needle-like member having the desired shape is formed with the good reproducibility and controllability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for forming a needle-like member, and the present invention relates to a method and an apparatus for forming a needle-like member, and the present invention relates to a method and an apparatus for forming a needle-like member, and the present invention relates to a method and an apparatus for forming a needle-like member. It is most suitable for use in forming.

[Summary of the invention]

The present invention provides a method and apparatus for forming a needle-like member, in which a needle-like member having a desired shape can be formed with good reproducibility and controllability by monitoring the etching state of a member to be etched using light. It was made so that it could be done.

[Conventional technology]

An emitter for a field ion source in an ion beam apparatus has conventionally been formed using an electrolytic polishing apparatus as shown in FIG. 5, for example. That is, as shown in FIG. 5, an emitter material 43 such as tungsten and an electrode plate 4 are immersed in an electrolytic solution 2 contained in an electrolytic bath 1, and the emitter material 3 and electrode plate 4 are used as an anode and an electrode, respectively. This is a method in which the tip of the emitter material 3 is shaped into a needle as shown by the dashed line by performing etching using an electrochemical reaction as a cathode.

When such an electrolytic polishing method is used, the timing to stop etching upon detecting that the tip of the emitter material 3 has become sharp due to polishing greatly affects the shape of the final emitter tip. Deciding when to stop etching is extremely important.

[Problem that the invention seeks to solve]

However, conventionally, the timing to stop etching has been determined based on the experience of the person operating the electrolytic polishing device, so as shown in FIGS. 6 and 7, the emitter 5 obtained by etching is In some cases, the tip 5a has a relatively sharp point, and in other cases, the radius of curvature of the tip 5a becomes large, resulting in poor reproducibility of the tip shape and almost no controllability.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and apparatus for forming a needle-shaped member, which corrects the above-mentioned drawbacks of the prior art.

[Means for solving problems]

A method for forming a needle-like member according to the present invention is a method for forming a needle-like member in which a needle-like member (for example, an emitter 5) is formed by etching a member to be etched (for example, an emitter material 3). The etching is performed while monitoring the etching state by irradiating the etching member with light.

Further, the needle-shaped member forming apparatus according to the present invention includes a light irradiation means (for example, a light source 7) for irradiating light onto a member to be etched (for example, an emitter material 3), and a light detection means (for example, a light source 7) for detecting the light. For example, a photodetector 8) is provided, and the etching of the member to be etched is controlled in accordance with the output of the photodetector.

[Effect]

By doing so, the end point of etching can be easily detected.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

First, a needle-like member forming apparatus according to an embodiment of the present invention will be described.

As shown in FIG. 1, in the needle-like member forming apparatus according to this embodiment, an emitter material 3 made of, for example, a tungsten wire and an electrode plate 4 are placed in an electrolytic solution 2 housed in an electrolytic bath 1 made of, for example, glass. Immersed. This electrode plate 4 is, for example, at ground potential, and a predetermined positive voltage is applied to the emitter material 3 by a predetermined power source 6 connected to one end of the emitter material 3.

On the other hand, a light 'a7 such as a laser light source and a photodetector 8 are provided on both sides of the electrolytic cell 1, and light (reference light) 9 from the light source 7 is passed through the wall of the electrolytic cell 1 and the electrolyte 2. The emitter material 3 is irradiated with light, and the transmitted light can be detected by a photodetector 8. Further, the photodetector 8 is connected to a control device 10, and this control device 10 is further connected to the power source 6. The control device 10 can control the output voltage (current) and output voltage (current) waveform of the power source 6 according to the output of the photodetector 8.

Next, a method for forming an emitter for an ion source using the needle-like member forming apparatus configured as described above will be explained.

As shown in FIG. 1, a light source 7 irradiates the emitter material 3 with light 9, a photodetector 8 detects the transmitted light, and a power source 6 applies a predetermined positive voltage to the emitter material 3, thereby performing electrolytic polishing. Start.

As the electrolytic polishing progresses and the tip of the emitter material 3 begins to become sharp as shown by the dashed line, the transmitted light intensity detected by the photodetector 8 increases, so when the transmitted light intensity reaches a predetermined value Alternatively, when the intensity of the transmitted light shows a certain change, the control device 10 is activated to lower the output voltage of the power source 6 to the ground potential and end the electrolytic polishing. At this time, the delay time from the time when the tip of the emitter material 3 becomes sufficiently sharp until the output voltage of the power source 6 is lowered to the ground potential by the control device 10 is determined as appropriate depending on the final shape of the emitter tip to be obtained. Set it to a value.

FIG. 2 shows an example of the shape of the tip of the emitter 5 obtained by the method for forming a needle-like member as described above. This second
As shown in the figure, the radius of curvature of the tip 5a of the emitter 5 is extremely small.

Furthermore, when the emitter 5 was repeatedly formed using the same method, the reproducibility of the shape of the emitter 5, especially the shape of the tip 5a, was extremely good.

As described above, according to the method for forming a needle-shaped member according to the above-described embodiment, the etching state is detected by irradiating the emitter material 3 with the light 9 from the light source 7 and detecting one transmitted light with the photodetector 8. Since etching is performed by electrolytic polishing while being monitored, the end point of etching can be easily detected by detecting the intensity of the transmitted light or its change.This allows emitter 5, which has an extremely small radius of curvature at the tip, to be formed with good reproducibility. Moreover, it can be formed with good controllability.

Furthermore, according to the needle-like member forming apparatus according to the above embodiment,
Since the formation of the emitter 5 as described above can be performed automatically, the emitter 5 can be formed without relying on the experience of the person operating the device, and therefore the emitter 5 can be formed with good reproducibility and controllability. It becomes possible to form.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made based on the technical idea of the present invention. For example, in the embodiment described above, light 9 from light source 7 is transmitted to emitter material 3.
However, as shown in FIG. 3, the light 9 from the light source 7 is irradiated onto the emitter material 3 and the scattered light by the emitter material 3 is detected as light. A beam splitter 11 is provided between the light source 7 and the emitter material 3 as shown in FIG.
The photodetector 8 may detect the light reflected by the light.

In the above-described embodiments, the present invention is applied to the formation of the emitter 5 for an ion source, but the present invention can also be applied to the formation of various needle-like members other than the emitter 5.

〔Effect of the invention〕

According to the method for forming a needle-shaped member according to the present invention, since etching is performed while monitoring the etching state by irradiating the member to be etched with light, the end point of etching can be easily detected. According to such a needle-like member forming apparatus, it is possible to automatically form a needle-like member, and therefore it is possible to form a needle-like member having a desired shape with good reproducibility and controllability. .

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for forming a needle-like member according to an embodiment of the present invention, and FIG. 2 is a diagram showing the tip of an emitter formed by a method for forming a needle-like member according to an embodiment of the present invention. A front view showing an example of the shape, FIG. 3 is a detailed explanatory diagram of the present invention in which scattered light by the emitter material is detected,
FIG. 4 is a detailed explanatory diagram of the present invention which detects reflected light from an emitter material, FIG. 5 is a schematic diagram of a conventional electrolytic polishing apparatus, and FIGS. FIG. 3 is a front view showing the shape of the tip of an emitter obtained using the conventional electrolytic polishing apparatus shown in FIG. In addition, in the symbols used in the drawings, 1-・-・・・・−−−−−−1 electrolytic cell 3−・−・・
・−・・・−Emitter material 5−−−−−−−−−−
--1.-Emitter 6-----Power supply 7-----------Light source 8----------・−・Photodetector 10−
・・・・−−−−−−1・−Control device.

Claims (1)

[Scope of Claims] 1. A method for forming a needle-like member in which the needle-like member is formed by etching a member to be etched, wherein the etching state is monitored by irradiating the member to be etched with light. A method for forming a needle-like member, characterized in that the above-mentioned etching is performed. 2. A light irradiation means for irradiating the member to be etched with light, and a light detection means for detecting the light, and etching of the member to be etched is controlled according to the output of the light detection means. A device for forming a needle-like member.