JPS63312968A - Melting and evaporating device - Google Patents

Abstract

PURPOSE:To easily monitor the liquid level of a material in a main vessel which is installed in a vacuum vessel and holds the material in a molten state via a preliminary melting vessel which supplies the material by connecting the main vessel and the preliminary melting vessel via a communicating pipe. CONSTITUTION:The material 7 which is to be melted and is housed in the main vessel 4 of the vacuum vessel 1 having an evacuation system 2 is maintained in the molten state by an electron beam 3 from an electron gun 10. The preliminary melting vessel 5 for supplying the above-mentioned material 7 to the above-mentioned main vessel 4 is disposed in the same vacuum vessel 1 of the above-mentioned melt evaporating device and the two vessels 4, 5 are connected by the communicating pipe 8 in the bottom; further, a heater 6 is disposed to the preliminary melting vessel 5 and the communicating pipe 8 to maintain the material 7 therein in the molten state. A thermocouple 9 is inserted into the above-mentioned preliminary melting vessel 5 and the liquid level in the vessel is detected from the detection temp. thereof. The liquid level of the material 7 in the main vessel 4 which is nearly the same as said vessel is thereby monitored.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an apparatus for melting and evaporating metals, etc., and in particular, an apparatus for easily monitoring the liquid level of a material to be melted and evaporated held in a melting container. The present invention relates to a dissolution evaporation device that can be used.

[Prior Art] For example, in a metal melting/evaporation device used in a metal vapor deposition device, fluctuations in the liquid level position of the material to be melted/evaporated held in a container etc. are caused by fluctuations in the spatial distribution of generated vapor. This will affect the utilization of the generated steam. Therefore, it is necessary to monitor and control the liquid level position of the material to be dissolved/evaporated. However, since the material to be melted and evaporated is kept at a high temperature within the container, and the liquid level where steam is generated reaches several thousand degrees, there has been no appropriate method for monitoring the liquid level position. In contact-type monitoring methods, there is a high possibility that the contact portion will melt due to temperature.

In addition, in non-contact monitoring methods, the source of light, sound waves, etc.
Maintenance and management of the device becomes difficult because the light receiving section is exposed to high heat generated steam from the liquid surface.

As a means for solving the above problem, there is a method described in Japanese Patent Application Laid-Open No. 53-30432, as shown in FIG. In this method, a supply pipe 11 for supplying the material to be melted and evaporated is installed outside a vacuum container 1 surrounding a melting container 4 holding a material 7 to be melted and evaporated, and the supply pipe 11 is connected to the melting container. 4, the material in the supply pipe 11 is maintained in a molten state by the heater 6, and an inert gas 12 is introduced into the supply pipe 11. The liquid level in the dissolution vessel 4 is controlled by changing the pressure of the inert gas 12 introduced into the supply pipe 11. Supply pipe 1
The level of the liquid in the dissolution container 4 is detected by the level detection device 13, thereby making it possible to indirectly monitor the liquid level in the dissolution container 4.

[Problems to be Solved by the Invention] In the above-mentioned prior art, the relationship between the liquid level in the melting container 4 and the liquid level in the supply pipe 11 is determined by the pressure in the vacuum container 1 and the liquid level in the supply pipe 11. Therefore, in order to know the former liquid level by detecting the latter liquid level, it is necessary to measure the above pressure difference, which is a troublesome problem. Therefore, consideration must be given to pressure changes due to disturbances caused by temperature changes. Further, there are problems such as oxidation of the heater 6 for keeping the material outside the vacuum container in a molten state.

SUMMARY OF THE INVENTION An object of the present invention is to provide a melting and evaporating apparatus that allows monitoring of the liquid level of a material to be melted and evaporated in a melting container without the above-mentioned problems.

[Means for Solving the Problems] The melting and evaporating apparatus of the present invention comprises a main container that holds the material to be melted and evaporated in a molten state, a preliminary melting container for supplying the material to the main container, and the main container. A communication pipe connected to the bottom of the container and the pre-melting container, and a heater for keeping the material in the pre-melting container and the communication pipe in a molten state are provided in the same vacuum container, and the material in the pre-melting container is provided in the same vacuum container. The present invention is characterized in that the liquid level of the material in the main container is monitored by monitoring the liquid level of the material.

[Function] The bottom of the main container for melting and evaporating the material to be melted and evaporated and the bottom of the pre-melting container for supplying the material in a molten state to the main container are connected by the communication pipe, By installing the main container and the pre-melting container, the liquid level of the material in the main container and the pre-melting container will be almost the same. This can be expressed numerically as follows.

gρ(TI)hl”P+-gρ(r2)hz÷P2...
...(1) However, g: Gravitational acceleration ρ (T): Density of liquid at temperature T h: Height of liquid level P: Pressure of atmosphere, subscript 1.2 is the main container, Compatible with pre-melting containers.

As mentioned above, by installing the main container and the preliminary melting container in the same vacuum container, P, = P, (2) is obtained. Therefore, equation (1) is gρ(y+)hl-g゛ρ(r2)hl...
... (3) becomes.

Therefore, if ρ(TI)·ρ(T2), the physical phenomenon will inevitably be hl - hl, and the liquid levels in the main container and the pre-melting container will be the same. The density of the liquid does not change greatly depending on the temperature, but only changes by a few percent at most, so even if the temperature difference is taken into account, the density is h1 and h2.

Therefore, by monitoring the liquid level in the pre-dissolution container, the liquid level in the main container can be monitored without the influence of pressure.

[Example] An embodiment of the present invention will be described below with reference to FIG.

As shown in FIG. 1, in a vacuum container 1 kept in a vacuum by an exhaust system 2, there is a main container 4 that holds a metal material 7 for deposition in a melted/evaporated state, and a metal material supplied to the main container 4. A pre-dissolution container 5 for pre-dissolving the liquid is installed, and the bottoms of these two containers are connected by a communication vibrator 8. A heater 6 is provided in the pre-dissolution container 5 and the communication vibe 8. Since the metal material 7 in the main container 4 needs to be evaporated, it is heated, for example, by the electron beam 3 of the high-energy density, high-output electron gun 10, and the temperature of the liquid surface and the vicinity of the liquid surface of the metal material in the main container 4 is heated. becomes quite high temperature.

On the other hand, since the metal material in the pre-melting container 5 only needs to be melted and does not need to be evaporated, the metal material in the pre-melting container 5 and the communication pipe 8 is maintained at a temperature higher than the melting point of the material by the heater 6. be done. Therefore, the liquid surface temperature of the material in the pre-melting container is kept lower than the liquid surface temperature of the material in the main container.

Since the main melting device 4 and the pre-melting container 5 are connected by the communication vibrator 8 in the same vacuum container 1, the liquid level of the molten metal material in the same vacuum container 4.5 becomes the same. (Of course, since there is a difference between the temperature of the metal material in the main melting vessel 4 and the temperature of the metal material in the pre-melting container 5 as described above, there is also a slight difference in the liquid level depending on the temperature difference. However, this is up to you, and the liquid level will be almost the same.) Therefore, from the temperature change of the thermocouple 9 inserted in the pre-melting container 5, the liquid level in the pre-melting container 5 and therefore in the main container 4 surface level can be detected. In this case, as mentioned above, the temperature of the material in the pre-melting container 5 is kept lower than that in the main container, so there is no risk of damage to the thermocouple 9. Furthermore, since the heater 6 is located inside the vacuum container 1, there is no fear of oxidation.

[Effects of the Invention] According to the present invention, since the main container and the pre-melting container are in the same vacuum container and are connected by a communication pipe, the liquid level of the molten material in both containers becomes the same, and the pressure difference is reduced. without any problems,
By monitoring the liquid level in the pre-dissolution container, the liquid level in the main container can be easily monitored. Further, since the heater for keeping the materials in the pre-melting container and the communication tube in a molten state is located inside the vacuum container, there is no risk of oxidation.

Additionally, by keeping the temperature of the material in the pre-melting vessel lower than the temperature of the material in the main vessel, damage to the detector that detects the liquid level in the pre-melting vessel and maintenance problems are reduced. be able to.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a melting evaporator according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a known melting evaporator. 1... Vacuum container 2... Exhaust system 3... Electron beam 4... Main container for melting/evaporation 5... Preliminary melting container 6... Heater 7... Material to be melted/evaporated 8... Communication vibrator 9... Thermocouple 10... Electron gun 11... Supply pipe 12... Inert gas
13...Level detection device Fig. 1 1-Vacuum container 4-Main container 5-Leakage volume Ng4 6-Hilter 7-8 Material in the container

Claims (1)

[Claims] a main container that holds the material to be melted and evaporated in a molten state, a pre-melting container for supplying the material to the main container, and a communication pipe connected to the bottoms of the main container and the pre-melting container;
The pre-melting container and a heater for keeping the material in the communication pipe in a molten state are provided in the same vacuum container, and by monitoring the liquid level of the material in the pre-melting container, A dissolution evaporation device characterized in that the liquid level of the above-mentioned material is monitored.