JPH0689795A - Plasma gun and plasma generation device - Google Patents

Abstract

PURPOSE:To enhance the producing efficiency by forming a plasma source outlet, anode, and outgoing port with elliptical sections, and generating a large area plasma easily. CONSTITUTION:A pair of convergence coils 5, 6 installed between a vacuum vessel 2 and a plasma gun 3 and counter-electrode 4 are formed in a ring having elliptical section longitudinally and the plasma P passing through its inside is converged into, approx. a sheet form, and the surface area of the plasma P is increased. The plasma gun 3 is surrounded by a cylindrical magnetic shield 7, and the shield is provided so that the line of magnetic force is not deviated to the plasma gun side. The outgoing port of plasma P and an anode installed alongside the inside surface of a plasma chamber are formed elliptical. A large area is obtained by forming the plasma with an elliptical section, in this manner, to lead to enhancement of the producing efficiency in the field of a film forming process and chemical processes, and also provision of the magnetic shield precludes influence of the line of magnetic force on the plasma which leads to enhancement of the reliability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma gun and a plasma generator used for plasma CVD, plasma melting, ion plating by arc discharge and the like.

[0002]

2. Description of the Related Art Conventionally, plasma generators have various uses such as direct irradiation of plasma generated by a plasma gun onto a processing base material, collision with vaporized molecules deposited on the processing base material and ionization. Is used for.

For example, as shown in FIG. 7, this plasma generator is provided with a plasma gun b on one side of a vacuum container a and an opposite electrode c on the other side so as to face the plasma gun b. , The plasma gun b and the counter electrode c
A crucible e in which a pair of focusing coils d is provided between the crucible e and an evaporating material is placed in the vacuum container a.
By disposing the processing base material f and providing the electron gun g, it can be used as an ion plating device.

Then, as shown in the figure, when the beam B is applied from the electron gun g to the evaporation material in the crucible e to evaporate it and the processing base material f disposed in the upper part of the vacuum container a is coated with it, The substantially cylindrical plasma emitted from the plasma gun b ionizes the vaporized particles to accelerate their arrival at the processing base material f on which the coating film is to be formed, so that a favorable coating film is formed. The focusing coil d also has a function of generating a magnetic field around the plasma emitted from the plasma gun b to prevent the plasma emitted from the plasma gun b from diffusing. Further, as shown in FIGS. 5 and 6, the plasma gun b has a cylindrical plasma source j for generating plasma and a pair of ring-shaped plasma sources in a cylindrical plasma chamber i having an emission port h at one end. Of the gas k introduced into the plasma source j is turned into plasma by arc discharge, and this is converted into the anode k, l.
The electric field of l pulls out and emits to the side of the emission port h.

[0005]

By the way, in the field of film forming process and chemical process, plasma having a large area as much as possible is required in order to improve the production efficiency. In the case of the generator, since the plasma emitted from the plasma gun b has a cylindrical shape, its area is small. Therefore, the inventors of the present invention first formed the focusing coil d into an elliptical shape and focused the cylindrical plasma emitted from the plasma gun b into a flat shape, so that the plasma generation device having an increased plasma area was first performed. Proposed (Japanese Patent Application No. 4-213)
No. 11, etc.).

However, in this method, the flatness of the plasma is limited only by the focusing coil d, so that the flatness is limited and it is difficult to obtain a larger area, that is, a sheet-shaped plasma. In addition, the magnetic force lines of the focusing coil d provided for further focusing the plasma may also flow into the plasma gun b, which may adversely affect the plasma generated in the plasma gun b.

Therefore, the present invention has been devised in order to effectively solve the above-mentioned problems, and the purpose thereof is to easily obtain a large-area plasma and to generate plasma by the magnetic field lines of the focusing coil. It is intended to provide a novel plasma gun and a plasma generator capable of preventing the adverse effects of the above.

[0008]

In order to achieve the above object, a first aspect of the present invention is to provide a plasma source having a plasma outlet in a plasma chamber having an outlet, and a plasma source provided downstream of the plasma source. A plasma gun having a ring-shaped anode for drawing out plasma generated in the plasma source, wherein the plasma outlet, the anode, and the outlet have a cross-sectional shape of an ellipse. In the invention of claim 1, a plasma gun for emitting plasma is provided on one side of the vacuum container and an opposite electrode is provided on the other side opposite to the plasma gun, and between the plasma gun and the opposite electrode,
A plasma generator provided with a focusing coil for forming magnetic lines of focus, wherein a magnetic shield made of a magnetic material is provided around the plasma gun so as to surround the plasma gun.

[0009]

As described above, according to the first aspect of the invention, since the plasma outlet, the anode and the emission port are formed in an elliptical cross-section, the plasma is extracted from the plasma outlet by the anode, passes through the anode and passes through the emission port. Until the plasma is emitted, all the plasma is formed into a conical shape having an elliptical cross section with a major axis 2 and a major axis 2 or more. Further, as described above, in the second invention, since the magnetic shield made of a magnetic material is provided around the plasma gun so as to surround the plasma gun, the plasma gun is shielded and the magnetic field lines generated from the focusing coil do not flow, It does not adversely affect the action of the plasma gun.

[0010]

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

FIG. 1 shows an embodiment of a plasma generator 1 according to the present invention. As shown in the figure, the plasma generator 1 is provided with a plasma gun 3 for emitting plasma on one side of the vacuum container 2, and on the other side opposite to the plasma gun 3 facing the plasma gun 3. To do
A counter electrode 4 is provided. Also, this plasma gun 3
A pair of focusing coils 5 and 6 are provided between the vacuum chamber 2 and the vacuum chamber 2 and between the counter electrode 4 and the vacuum chamber 2 to generate a magnetic field line as shown in the drawing and to emit plasma P emitted from the plasma gun 3. Is guided through the vacuum container 2 to the counter electrode 4. Further, as shown in FIG. 2, the focusing coils 5 and 6 are formed in a ring shape having an elliptical shape in the longitudinal direction of the cross section, and focus the plasma P passing through the inside into a substantially sheet shape, and The surface area of the plasma P is increased. Further, as shown in the figure, a magnetic shield 7 made of a cylindrical magnetic material is provided around the plasma gun 3 so as to surround the plasma gun 3, and magnetic force lines generated by the focusing coils 5 and 6 are generated in the plasma gun. It is shielded so that it does not flow to the 3 side.

As shown in FIG. 3, the plasma gun 3 has a plasma source 9 serving as a cathode for generating the plasma P in a cylindrical plasma chamber 8 having an exit 8a for the plasma P formed at one end. And two ring-shaped anodes 10 and 11 which are provided along the inner peripheral surface of the plasma chamber 8 and have a coil therein. Further, as shown in FIG. 4, each of the plasma outlet 9a, the anodes 10 and 11, and the outlet 8 is formed in an elliptical shape in which the vertical axis B is 1: 2 or more with respect to the horizontal axis A. The cross-sectional area of is such that the opening area of the plasma outlet 9a <anode 10 <anode 11 <exit opening 8 gradually increases toward the downstream side.

Next, the operation of this embodiment will be described.

As shown in FIG. 3, when a gas G of nitrogen, argon, hydrogen or the like is passed through the plasma source 9 of the plasma gun 3 and a predetermined voltage is applied, the gas G is ionized to become ions and electrons, and plasma Generate P. Then, the plasma P is first drawn out from the plasma outlet 9a by the anode 10, further accelerated by the anode 11 and emitted from the emission port 8a of the plasma chamber 8 to the vacuum container 2 side.
At this time, as described above, the plasma outlet 9a, the anode 1
Since 0, the anode 11, and the emission port 8a are formed in an elliptical shape, the plasma P emitted from the emission port 8a has an elliptical cross section with a horizontal axis A and a vertical axis B of 1: 2 or more. The light is emitted in the shape of a cone.

Next, the conical plasma P having an elliptical cross section and emitted from the emission port 8a has a pair of focusing coils 5 and 6.
As shown in FIG. 2, the diffusion state is converged by the magnetic force lines M generated as shown in FIG. 1, and most of the diffused state reaches the counter electrode 4 after being formed into the band-shaped plasma P having a substantially sheet-shaped cross section. become. Further, the magnetic force lines M flowing to the plasma gun 3 side are transmitted through the magnetic shield 7, flow from the ends to the inside of the focusing coils 5 and 6, and serve to focus the plasma P.

As described above, in the plasma gun of the present invention, since the plasma outlet, the anode, and the outlet of the plasma chamber constituting the plasma gun are each formed in an elliptical shape, the plasma P having an elliptical cross section can be emitted. You can Therefore,
Since the plasma P emitted from the plasma gun is also elliptical in cross section in advance, the flatness due to the focusing coil is reduced and a sheet-shaped plasma can be easily obtained. Further, as described above, since the magnetic shield is provided around the plasma gun so as to surround the plasma gun, the magnetic force lines M generated in the focusing coil do not flow to the plasma gun side, and The adverse effect on the generated plasma is prevented in advance.

[0017]

In summary, the present invention has the following excellent effects.

By making the plasma emitted from the plasma gun have an elliptical cross section in advance, a large area plasma can be easily obtained, which contributes to the improvement of the production efficiency in the field of film forming process, chemical process and the like. You can

By providing a magnetic shield around the plasma gun, it is possible to prevent adverse effects on the plasma due to the magnetic lines of force of the focusing coil, so that the reliability of the apparatus is greatly improved.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a plasma generator of the present invention.

FIG. 2 is a view on arrow AA in FIG.

FIG. 3 is a side sectional view showing an embodiment of the plasma gun of the present invention.

FIG. 4 is a view on arrow AA in FIG.

FIG. 5 is a side sectional view showing an example of a conventional plasma gun.

FIG. 6 is a view on arrow AA in FIG.

FIG. 7 is a schematic view showing an embodiment of an ion plating apparatus using a conventional plasma generator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plasma generator 2 Vacuum container 3 Plasma gun 4 Counter electrode 5,6 Focusing coil 7 Magnetic shield 8 Plasma chamber 8a Outlet port 9 Plasma source 9a Plasma outlet 10, 11 Anode

Front page continuation (72) Inventor Takashi Nakabayashi 3-15-15 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toji Technical Center (72) Inventor ▲ Kuwa ▼ hara Hajime Toyosu, Koto-ku, Tokyo 1-15 Ishikawajima Harima Heavy Industries Co., Ltd. Toji Technical Center

Claims (2)

[Claims] 1. A plasma source provided with a plasma outlet in a plasma chamber provided with an outlet, and a ring-shaped anode provided downstream of the plasma source for extracting plasma generated in the plasma source. A plasma gun including: a plasma gun, wherein the plasma outlet, the anode, and the outlet have a cross-sectional shape of an ellipse. 2. A plasma gun for emitting plasma is provided on one side of the vacuum container, and an opposite electrode is provided on the other side opposite to the plasma gun, and a magnetic force line for focusing is provided between the plasma gun and the opposite electrode. In a plasma generator provided with a focusing coil for forming, around the plasma gun,
A plasma generator characterized in that a magnetic shield made of a magnetic material is provided so as to surround this.