JPS6036470B2 - Ion plating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ion plating apparatus, and more particularly to an ion plating apparatus that uses an electron beam melting evaporation source as an evaporation source and is provided with a mechanism for stabilizing the driving of the apparatus.

This will be explained below with reference to the drawings. FIG. 1 is a sectional view showing the structure of the ion plating apparatus of the present invention. Mechanism 30
Other than this, it is the same as the conventional device known as a multi-cathode DC excitation system.

In this apparatus, in a vacuum chamber 3 having an exhaust system 1 and a gas inlet 2, an electron beam melting and evaporation source 4 at ground potential and a substrate 10, which is an object to be processed, are disposed facing each other. The electron beam melting and evaporation source 4 includes an electron beam filament 7 heated by a filament power source 6 and an electron beam accelerating power source 5.

Since the substrate 1 held by the substrate holder 11 is applied with a negative voltage with respect to the ground potential by the substrate power supply 12, the substrate 1 functions as the cathode 10.

On the other hand, a thermionic filament 13 heated by a filament power source 14 is arranged near the substrate 10.
Since a negative voltage with respect to the ground potential is applied by the cathode power supply 15, this also functions as the cathode 13. Such an apparatus is called a multi-cathode DC excitation type ion plating apparatus.

In this device, after a vacuum chamber 3 is evacuated via an exhaust system 1, a certain amount of gas is introduced from a gas inlet 2 to maintain the degree of vacuum at around 10-3 Torr, and an evaporation source 4 and a cathode 10.
13, the introduced gas is discharged and becomes a plasma state, which fills the vacuum chamber 3.

In this state, when the filament power source 6 and the electron beam accelerating power source 5 are driven to irradiate the evaporative substance 8 with an electron beam from the electron beam filament 7, the evaporative substance 8 is melted and emits vapor.

The evaporated substance vapor is ionized by the action of plasma, or further reacts with the introduced gas to form a compound, and the substrate 1
It is electrostatically accelerated and deposited on the surface of 0 to form a film.

Although the cathode 13 made of the thermionic emission filament 13 is not an essential member, by arranging it, it is possible to reduce the negative voltage applied to the substrate 10, and the sputtering effect on the substrate surface due to positive ions is alleviated. Film deposition speed is improved. Further, the electrons emitted from the thermionic emission filament 13 significantly improve plasma density and ionization efficiency.

In such an ion plating apparatus, the factors that influence the characteristics of the film formed include the evaporation rate of the evaporated substance, the introduced gas pressure, the substrate power supply voltage, the cathode power supply voltage, and thermionic emission filament current. It is relatively easy to set the remaining factors other than the evaporation rate of the substance to predetermined values and maintain them stably.

On the other hand, the most important factor, the evaporation rate of the evaporated substance, is a factor that is extremely difficult to control, especially when an electron beam melting evaporation source is used as the evaporation source.

Therefore, an object of the present invention is to improve the reproducibility of film-forming conditions and homogenize the properties of a film by stabilizing the evaporation rate of evaporated substances.

For the above-mentioned purpose, the present invention is provided with a mechanism for detecting the height of the sun-falling surface of the evaporated material and an evaporated-material replenishment mechanism, so that the height of the sun-falling surface can be adjusted to a predetermined position. Since the vapor pressure of the evaporated substance is determined by the temperature of the molten metal, it is necessary to keep the temperature of the molten metal constant in order to keep the evaporation rate constant.

Incidentally, the output of an electron beam melting and evaporation source is controlled by the electron beam filament current and electron beam acceleration voltage, but even when these values are set constant, the temperature of the flaw depends on the amount of evaporated material, and therefore the molten metal. Varies between large and medium depending on the height of the surface.

The reason for this is that the irradiation position and irradiation area of the electron beam change depending on the height of the flawed surface, and the contact area with the water-cooled rubbo changes depending on the amount of evaporated material, resulting in fluctuations in cooling efficiency. The amount of evaporated material decreases with operating time and the height of the lagoon surface decreases, so in order to keep it in place, the height of the falling sun surface is detected and the evaporated material is replenished as necessary. It is necessary to.

The present invention has been made based on the above knowledge, and as shown in the figure, a light emitting section 21 that irradiates a light beam to the evaporated substance flawed surface 9 and a light receiving section 22 that receives reflected light from the moat surface 9.
In addition to providing a height detection mechanism consisting of the following, an evaporative substance replenishment mechanism 30 is provided that appropriately replenishes evaporative substance to the evaporation source 4 by operation from outside the vacuum chamber. As the light source of the light emitting section 21, it is sufficient to use light with a wavelength that can be detected separately from the incandescent light spectrum of the molten metal, or to detect only the pulse component using pulse-modulated laser light.

There is no need to follow and detect the height of the melted surface in an analogical manner; it is sufficient to detect whether it is at a predetermined height.

As the evaporated substance replenishment mechanism 30, a commonly used electromagnetic vibration type or motor driven type mechanism can be used. Since the device of the present invention is equipped with the above-described mechanism, it is possible to maintain the evaporation rate constant over a long period of time, which was conventionally controlled by trial and error using the electron beam filament current and electron beam acceleration voltage. This method is extremely effective in improving the reproducibility of film-forming conditions, and makes it possible to always form a uniform film.

[Brief explanation of drawings]

FIG. 1 is a vague sectional view showing the configuration of the ion plating apparatus of the present invention. 1...Exhaust system, 2...Gas inlet, 3
... Vacuum chamber, 4 ... Electron beam melting and evaporation source, 8 ... Evaporated substance, 9 ... Evaporated substance molten metal surface, 10 ... Substrate , 11... Substrate holder, 21... Light emitting section, 22... Light receiving section, 3
0... Evaporated substance replenishment mechanism.

Claims (1)

[Claims] 1. In a vacuum chamber having an exhaust system and a gas inlet, an electron beam melting evaporation source at ground potential and a substrate to which a negative voltage is applied with respect to the ground potential are placed facing each other, and the evaporated material vapor from the evaporation source is In an ion plating apparatus that ionizes the introduced gas from the gas inlet and coats the surface of the substrate held in the substrate holder with the evaporated substance or a reaction product between the evaporated substance and the introduced gas, the evaporated substance of the evaporation source An evaporated substance molten metal surface height detection mechanism comprising a light emitting part that irradiates a light beam onto the molten metal surface and a light receiving part that receives reflected light from the molten metal surface, and an evaporated substance replenishment mechanism that replenishes the evaporation material to the evaporation source. An ion plating apparatus characterized in that the height of the molten metal surface of the evaporated substance can be adjusted to a predetermined position.