JPH089775B2 - Ion plating method and apparatus - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ion plating method and apparatus, and more particularly to an ion plating method and apparatus suitable for forming a film on a wide substrate at a high speed.

[Prior Art] In recent years, it has been attempted to increase the added value by forming a dry process film on a wide steel plate, for example, a cold rolled steel plate. Among them, ion plating is attracting attention as a method having excellent adhesion and denseness of the coating and high productivity. In order to improve productivity by ion plating, it is necessary to evaporate the coating material at high speed, and a high-power electron gun is advantageous as a heating source for the material. However, there are many technical difficulties in stably ionizing a material evaporated at a high speed with a high ionization rate, and a method applicable to a wide steel sheet on an industrial scale has not been established yet.

Japanese Patent Publication No. 57-57553 proposes a method in which an electron gun is used as a heating source and an electrode is arranged in the vicinity of the crucible to increase the ionization rate and improve the film quality. But this method
Since the discharge becomes unstable during high-speed film formation, it can be applied only to small-scale batch processing, and it is difficult to perform high-speed ion plating on a large-area strip plate using a wide crucible.

Japanese Patent Laid-Open No. 155369/1982 proposes a method in which vaporized particles are focused by a hood above the crucible and then ionized by a positive electrode and a filament for thermionic emission arranged above the hood. According to this, a stable discharge can be obtained even at high-speed film formation, but the filament is heavily consumed and cannot be applied to a continuous device for actual production.

Japanese Patent Laid-Open No. 63-45365 discloses, as shown in FIG.
A method has been proposed in which the entire crucible 3 is covered with an internal chamber 6 having an opening 8 above, and the vapor flow ejected from the opening 8 is ionized by a positive electrode 9 above the opening 8. According to this method, stable discharge can be obtained even during high-speed film formation, and long-time operation can be endured. However, since the electrode 9 above the inner chamber 6 is far from the crucible 3, it is not possible to sufficiently accelerate the thermoelectrons generated from the evaporation material 4, so that the ionization rate of the evaporation particles is insufficient, and There is a problem that the ionization rate is significantly reduced during high-speed film formation.

[Technical Problem to be Solved by the Invention] The present invention has been made in order to solve the problems of the above-mentioned prior art, and its object is to provide a strip plate, particularly a wide strip plate at high speed and stably. Moreover, the present invention provides an ion plating method and apparatus that obtains excellent film quality by performing ion plating at a high ionization rate.

[Means for Solving the Problems] The inventors of the present invention have conducted extensive studies in accordance with the purpose of steam, and as a result,
When the evaporation material in the crucible is heated and evaporated by an electron gun, and the vapor flow is ionized by the electrode to which a positive voltage is applied, a hood for converging the vapor flow is placed above the crucible, and the electrode is placed inside the hood. It has been found that, by placing it, the discharge can be stabilized and the ionization rate can be improved even during high-speed film formation, and the present invention has been completed.

[Operation] That is, by installing a hood above the crucible and installing a positive electrode inside the hood, diffusion of the vapor flow is prevented, and turbulence of the vapor due to the surface state of the vaporizer during high-speed evaporation is suppressed. Therefore, the discharge is stable. Furthermore, the vapor pressure on the surface of the evaporation material is significantly improved during high-speed film formation, and even if the mean free path of the thermoelectrons generated from the surface of the evaporation material is shortened, the electrode can be brought closer to the crucible surface, so it is still sufficient. It becomes possible to accelerate thermoelectrons, and a high ionization rate can be maintained.

[Embodiment] The present invention will be described below with reference to an embodiment shown in FIG. The illustrated ion plating device is arranged in a vacuum chamber 1 that holds a vacuum atmosphere, and a strip plate 11 penetrates and runs above the inside thereof. A crucible 3 is arranged in the lower part of the vacuum chamber 1, and the evaporation material M is placed in the crucible 3.
Is included. The evaporation material 4 includes Ni, Co, Fe, Ti, Zr, Ta, V,
Cr, Mn, Mg, etc. are mentioned together with Hf, etc. Vacuum tank 1
An electron gun 12 is mounted on one side of the so as to irradiate the surface of the vapor material 4 with the electron beam 7. Crucible 3 and strip
The hood 5 is disposed between the hood 5 and the hood 5, and the hood 5 has a part of the side through which the electron beam 7 passes and an opening 8 at the top.
have. An electrode 9 is arranged inside the hood 5, and the electrode 9 is formed in a rectangular frame shape. The electrode 9 is connected to the positive electrode side of the DC power supply 13, and the crucible 3 is connected to the negative electrode side of the DC power supply 13.

In this device, the evaporation material 4 in the crucible 3 placed inside
The electron beam 12 is emitted from the electron gun 12 to heat and evaporate the evaporation material 4. Then, by applying a positive voltage to the electrode 9, the vapor flow is ionized by the thermoelectrons generated from the evaporation material 4. The ionized vapor is focused in the hood 5, passes through the hood 5 upper opening 8 and is above the strip.
Attach to 11.

In this device, since the hood 5 is provided above the crucible 3, the diffusion of the vapor flow is prevented, and the turbulence of the vapor due to the surface state of the evaporant during high-speed evaporation is suppressed, and as a result, the discharge is stabilized. Further, since the electrode 9 is installed inside the hood 5, the electrode 9 can be brought as close as possible to the evaporation material 4 within a range where it does not interfere with the electron beam. Therefore, even when the mean free path of the thermoelectrons generated on the surface of the evaporation material becomes short during high-speed film formation, the electrons can be sufficiently accelerated and a high ionization rate can be maintained.

FIG. 2 is a graph showing the relationship between the film formation rate and the ionization rate when the apparatus shown in FIG. 1 is used, compared with the case where the apparatus shown in FIG. 3 is used. In this case, Ti was used as the evaporation material, and the electron gun output was changed between 40 and 150 KW. The voltage applied to the electrodes was +40 to + 50V. The ionization rate was calculated from the current value flowing through the substrate. From FIG. 2, it can be seen that the ionization rate sharply decreases as the film formation rate increases in the conventional method, whereas the present invention can maintain a higher ionization rate than the conventional method even during high-speed film formation. .

[Effects of the Invention] As described above, according to the present invention, when ion-plating a strip plate, particularly a wide strip plate, the discharge is stable even at a high-speed film formation, and the film is formed with a high ionization rate. Is possible.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an ion plating apparatus according to the present invention, and FIG. 2 shows the relationship between the film formation rate and the ionization rate when the apparatus according to the present invention shown in FIG. 3 and FIG. 3 which are shown in comparison with the case where the conventional ion plating apparatus is used.

Claims (2)

[Claims] 1. A method of ion-plating a running strip, which comprises heating and evaporating an evaporation material placed in a crucible with a beam of an electron gun to generate a vapor flow, and concentrating the generated vapor flow with a hood. A step of applying a positive electrode to the crucible to the electrode in the hood, and ionizing the vapor flow by thermoelectrons generated from the evaporation material;
Depositing a focused and ionized vapor stream onto a strip running above the hood. 2. A device for ion-plating a running strip, a crucible containing an evaporation material, an electron gun for heating and evaporating the evaporation material in the crucible to form a vapor flow, and an upper part of the vapor crucible. A strip that is disposed above the hood and has a hood that focuses the vapor flow, an electrode that is disposed in the hood, and a power source that applies a positive electrode to the crucible to the electrode. An ion plating device designed to attach an ionized vapor stream.