JPH03274264A - Weight monitoring system for molten material or sublimating material and its weight control system - Google Patents

Abstract

PURPOSE:To surely and directly monitor the weight of molten material or sublimating material, etc., with high accuracy by placing the above-mentioned material together with the vessel containing the material on a weight detecting means, and detecting the change of detected weight by a detecting means. CONSTITUTION:Material 1 of vapor deposition, such as molten material or sublimating material, etc., is contained and held in the holding means consisting of a container 2, such as crucible, and a hearth 3. This holding means is placed on the weight detecting means 4 with the insulation means 8 having cooling water passages 10 between. This weight detecting means 4 has a parallel beam structure 5 provided with a strain gauge 6 which detects the total weight of the material 1 and the holding means. The weight detecting means detects the change of weight of the material 1 from the detected weight to directly monitor the weight of the material. A material supply means is controlled according to the detected value of changing weight to control the weight of the material 1 in the holding means with high accuracy, and thus, with the result that the stable production of high yield is carried out for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for monitoring the weight of molten or sublimable material and a device for controlling the weight.

Conventional technology Conventionally, when producing functional films, which are used as materials for capacitors, magnetic tapes, etc., by forming a thin film on a long film using a vacuum evaporation method, a large amount of steam is constantly applied over a long period of time. must be generated at an evaporation rate of For this purpose, it is necessary to monitor the amount of vapor deposition material melted within the container and keep it constant. As such, in order to monitor the amount of vapor deposited material, e.g.
There is a method shown in the 968 publication. In this method, the main container and the preliminary container are connected through a communication pipe, and the amount of the vapor deposition material in the main container is indirectly monitored by monitoring the liquid level of the vapor deposition material in the preliminary container.

Problems to be Solved by the Invention However, the conventional method described above requires a preliminary container, a communication pipe, and a heater to keep the material in the communication pipe in a molten state in addition to the main container, resulting in a very complicated structure. There was a problem. In particular, in order to apply the above structure to high melting point materials, l! It is necessary to make it from ceramics with i4 thermal properties, but this has been extremely difficult due to its complex structure. Furthermore, even if it were possible to make one, its lifespan was short because the structure was complicated and it was prone to cracking during heating or cooling. Furthermore, the material in the communication tube must be kept in a high-temperature molten state, which not only requires a large amount of energy but also places a very large load on the heater, making it impractical to apply to high-melting-point materials because the heater life is short. It was difficult.

Furthermore, with this method, it was not possible to monitor chromium, which is a sublimable metal material, or oxides, etc., which do not become a liquid.

Therefore, the present invention provides a weight monitoring device for molten material or sublimable material, which can directly monitor the weight of molten material or sublimable material with high precision, has a long life, and is highly practical. The object of the present invention is to provide a weight control device that can control the weight.

Means for Solving the Problems The present invention as set forth in claim 1 provides a holding means for containing and holding a molten material or a sublimable material, a weight detection means for detecting the total weight of the material and the holding means, This is a weight monitoring device for a molten material or a sublimable material, comprising a weight detecting means for detecting a change in the weight of the material from a change in the total weight.

Further, the present invention according to claim 2 includes: a holding means for storing and holding a molten material or a sublimable material; a weight detecting means for detecting the total weight of the material and the holding means;
A weight detecting means for detecting a change in the weight of the material from a change in the total weight, and a heat insulating means provided between the melting material or sublimable material and the weight detecting means or in the weight detecting means. This is a weight monitoring device for molten materials or sublimable materials.

The present invention according to claim 4 also provides a holding member that accommodates and holds a molten material or a sublimable material, a support means that rotatably supports the holding member accommodated therein, and a rotational force of the holding member. and a weight detecting means for detecting the total weight of the melted material or sublimable material and the holding member containing the material, and the melted material or sublimable material and the weight detecting means. and a cooling liquid supplied using the structure of the support means.

Further, the present invention according to claim 5 includes: a holding means for storing and holding a molten material or a sublimable material; a weight detecting means for detecting the total weight of the material and the holding means;
A replenishing means for replenishing the material into the holding means, and a control means for controlling the replenishing means so that the weight of the material becomes a required value based on a weight signal of the material from the weight detecting means. This is a weight control device for melting material or sublimable material.

Further, the present invention according to claim 6 provides a holding means for storing and holding a molten material or a sublimable material, a heating means for heating and melting or sublimating the material, and a total weight of the material and the holding means. weight detection means for detecting the
and a control means for controlling the heating means so that the weight reduction rate of the material reaches a desired value based on the weight signal of the material from the weight detection means. It is a material weight control device.

In the present invention as set forth in claim 1, the holding means accommodates and holds the molten material or the sublimable material, the weight detecting means detects the total weight of the material and the holding means, and the weight detecting means detects the total weight of the material and the holding means. A change in the weight of the material is detected from a change in weight. With the above configuration, it is possible to provide a weight monitoring device that can directly monitor the weight of a molten material or a sublimable material with high precision, has a long life, and is highly practical.

Further, in the present invention according to claim 2, the holding means accommodates and holds the molten material or the sublimable material, the weight detecting means detects the total weight of the material and the holding means, and the weight detecting means detects the total weight of the material and the holding means. A change in the weight of the material is detected from a change in the total weight, and a heat insulating means is provided between the melting material or the sublimable material and the weight detecting means, or in the weight detecting means to perform heat insulation. With the above configuration, it is possible to eliminate errors in the weight detection means due to temperature rise, thereby providing a highly practical weight monitoring device that can directly monitor the weight of molten material or sublimable material with high precision, and has a long service life. be able to.

Further, in the present invention according to claim 4, the holding member accommodates and holds the molten material or the sublimable material, the supporting means rotatably supports the holding member accommodated therein, and the weight detection means The total weight of the molten material or sublimable material and the holding member containing the material is detected by detecting the rotational force of the member, and the cooling liquid is connected to the molten material or sublimable material and the weight sensing means. and is supplied by utilizing the structure of the support means. The above configuration makes it less susceptible to the effects of the weight and vibration of the vibrator through which the cooling liquid flows, making it possible to directly monitor the weight of molten materials or sublimable materials with high precision, while also providing a highly practical weight with a long life. Monitoring equipment can be provided.

Further, in the present invention as set forth in claim 5, the holding means accommodates and holds the molten material or the sublimable material, the weight detection means detects the total weight of the material and the holding means, and the replenishing means detects the total weight of the material and the holding means. The material is replenished into the means, and the control means controls the replenishment means so that the weight of the material reaches a required value based on the weight signal of the material from the weight detection means. With the above configuration, it is possible to directly monitor the weight of a molten material or a sublimable material over a long period of time with high precision, and to provide a weight control device that can control the weight to a required value with high precision while replenishing the material. be able to.

Further, in the present invention as set forth in claim 6, when the holding means accommodates and holds the molten material or the sublimable material, the heating means heats and melts or sublimates the material, and the weight detecting means receives the material and the holding material. detecting the total weight of the means;
A control means controls the heating means based on the weight signal of the material from the weight detection means so that the weight reduction rate of the material becomes a desired value. With the above configuration, it is possible to provide a weight control device that can directly monitor the weight of a molten material or a sublimable material with long-term component accuracy, and can control the rate of decrease in weight to a desired value with high precision.

Example Embodiments of the present invention will be described below with reference to the drawings.

First, a molten material weight monitoring device in an embodiment for monitoring and controlling the weight of molten evaporation material in a vacuum evaporation method will be described along with its operation with reference to FIGS. 1 and 2.

In FIG. 1, reference numeral 1 denotes a vapor deposition material, which is housed in a container 2 such as a crucible made of refractory material as an example of a holding means, and is heated by, for example, a known electron beam heating means (not shown). It is melted. Reference numeral 3 denotes a hearth, which holds the container 2 so that even if a crack occurs in the container 2, the container 2 will not be rapidly damaged and the vapor deposition material l inside will not flow out. be done. The vapor deposition material 1, the container 2, and the hearth 3 are placed on a weight detection section 4, which is an example of weight detection means having a parallel beam structure. Since the beam 5 of the weight detection section 4 deforms according to the total weight of the objects placed thereon, the strain generated by the deformation is detected by the strain gauge 6. Furthermore, the weight of the vapor deposition material 1 is detected by detecting the previous total weight based on the signal from the strain gauge 6 using a weight detection device 7 as an example of weight detection means.

Further, the weight detection section 4 is provided with a heat insulating section 8 as an example of heat insulating means having a flow path 10 therein, and cooling vibes 11a and 11b are connected from the outside to the flow path lO. . Then fill the inside of them with cooling water and
By flowing in the direction of 0.21 and circulating inside, the weight detection section 4 is insulated from the vapor deposition material 1, and errors in the weight detection section 4 due to temperature rise are prevented. Also, if there is a pressure fluctuation in the cooling water, the cooling vibration 11a will be affected.

11b and transmitted to the weight detecting section 4, the vibration becomes noise and interferes with accurate weight detection. Furthermore, even if the cooling water flows into the weight detection section 4 while containing air bubbles, the weight of the cooling water will change accordingly, resulting in an error.

Here, in order to remove them, a pressure buffer 12 and a bubble trap 13 are provided in the middle of the cooling vibrator lla on the side where the weight detecting section 40 enters.

Pressure fluctuation buffer 12 for buffering pressure fluctuations of cooling water
For example, the system has a space in which gas 15 is stored above a large buffer tank in which cooling water is stored. The air bubble trap 13 for removing air bubbles from the cooling water has a structure in which, for example, a partition plate 17 with a gap at the top is internally membraned, and a space 16 in which gas is collected is provided at the top of the partition plate 17. Air bubbles contained in the cooling water are collected in the space 16.

Incidentally, reference numerals 14a and 14b are flexible tubes, which are designed to prevent excess load from being applied to the weight detection section 4 and to prevent measurement errors from occurring.

In the above configuration, since the weight is directly detected, it can also be applied to monitoring the amount of evaporation material that is not in a liquid state, such as C, which is a sublimable metal material, or oxide.

In addition, if the net weight of the vapor deposition material 1 is required, for example, measure the weight in advance without adding the vapor deposition material Fi1, and subtract the previous value from the weight with the vapor deposition material 1 added. is required.

Although the case where cooling water is used as the heat insulating means 8 is shown, a structure may also be adopted in which a heat insulating material such as ceramic is interposed to prevent heat from flowing into the weight detecting section 4, and the temperature rise of the weight detecting section 4 can be kept at an allowable value. As long as it can be suppressed within

The weight detection section 4 may be a hook-shaped or compression-type load cell, or an actuation transformer-type load sensor other than the above, and is not limited to these, but it may have a parallel beam structure as shown in Fig. 1. When used, the strain gauge 6 as shown in Fig.
It also has a structure that seals inert gas inside with a bellows 19 to seal it from the outside world and prevent it from changing over time.
Even when it is put into a vacuum chamber and evacuated, the strain in the sensitivity direction of the parallel beam gauge 6 is hard to change, so there is an advantage that weight drift is hard to occur.

Next, another embodiment of the present invention will be described with reference to FIGS. 2(a) and 2(b). In the embodiment shown in FIG. 1, the weight of the vapor deposition material l, the container 2, and the hearth 3 are all applied to the weight detection part 4, but in this example, the vapor deposition material l, the container as an example of the holding member 2. The hearth 3 provided with the heat insulating part 38 is supported by a bearing as an example of supporting means by the stand 30 and the weight detecting part 33. Note that the same components as those in the embodiment shown in FIG. 1 will be described using the same numbers.

The hearth 3 is provided with a hollow shaft 31 at a distance a from the center of gravity C when the vapor deposition material 1, the container 2, and the hearth 3 are considered as one body. It is supported by a stand 30. In addition, the weight detection section 3
3 is provided to support the hearth 3 at a position away from the center of gravity G on the opposite side of the hollow shaft.

Therefore, the total type tw applied to the center of gravity G is WXa/(a + b) for the weight detection section 33 and the bearing on the stand 30, respectively.

The strain gauge 35 detects the deformation that occurs in the cantilever beam 34 in accordance with the weight applied by dividing the cantilever beam 34 into WXb,/(a+b). Based on the signal from the strain gauge 35, the weight detection device 7 detects the weight.

FIG. 2(b) shows a schematic cross-section of one side of the bearing portion 30.

Hollow shaft as shown: (1 has flexible tube 14
a is connected, and cooling water flows into the flow path lO from the direction of arrow 20 and flows out from the other hollow shaft (not shown). By allowing the cooling water to flow in and out through the hollow shaft 31 in this way, the weight and vibration of the flexible tube 14a are not directly applied to the object to be measured, such as the hearth 3, so that the weight can be detected with higher accuracy. be.

With the above configuration, it is possible to eliminate vibrations transmitted from the cooling vibrator to the weight detection section, so that the weight of the vapor deposition material 10 can be directly monitored with high precision.

Next, a molten material weight control device according to another embodiment of the present invention will be explained using FIG. 3. Note that the same components as those in the embodiment shown in FIG. 1 will be described using the same numbers.

The replenishment material rod 40 that is replenished into the container 2 is sandwiched between a drive roller 41 and a guide roller 46 driven by a motor 42, and is sent toward the vapor deposition material l, and is melted when it comes into contact with the liquid surface 47, causing the material to melt. Replenishment will take place. The weight control device 45 is
Value of weight signal from weight detection device 7 and target WiD
The deviation of o is equalized, and if D<Do, a command is sent to the motor control device 43 to drive the motor 42 and replenish the material.

Although the shape of the replenishment material has been described above as being rod-like, it is not limited to this, and may be wire-like, plate-like, granular, or other shapes.

According to the above configuration, when the weight of the vapor deposition material l decreases due to evaporation, the amount of decrease is detected, and the vapor deposition material is replenished to compensate for the decrease, so that the weight of the vapor deposition material l is always kept constant. be able to. Therefore, it becomes possible to perform deposition at a constant evaporation rate over a long period of time.

Furthermore, a molten material weight control device according to another embodiment of the present invention will be explained using FIG. 4.

Note that the same components as those in the above embodiment will be described using the same numbers.

In the embodiment shown in FIG. 3, the weight of the vapor deposition material l in the container 2 is controlled to be constant by replenishing the vapor deposition material, thereby making the evaporation rate constant. In this embodiment, when the evaporation material is not replenished, the evaporation rate is kept constant by making the rate of weight decrease constant as shown below.

The vapor deposition material 1 is heated and melted and evaporated using a known electron beam heating device. The outline of the electron beam heating device is shown in FIG. 4. An electron beam control bag @50 causes a current to flow through a filament 51 to generate thermoelectrons, and then an accelerating voltage is applied to the electrons as an electron beam 52, which releases the evaporation material. 1. The power of the electron beam 52 is controlled by controlling the current flowing through the filament 51 and the accelerating voltage by the electron beam control device 50. Although not shown, the irradiation position of the electron beam 52 is controlled by controlling the external magnetic field applied to the electron beam 52ζ.

The melted deposition material l evaporates and its weight gradually decreases. Therefore, when the electron beam 52 of the same power is irradiated onto the vapor deposition material 1, the temperature of the vapor deposition material 1 gradually increases, and the evaporation rate increases. Therefore, the weight reduction speed control device 53 calculates the weight reduction speed ΔD/Δt based on the weight signal from the weight detection device 7 or 6, and further calculates the weight reduction speed ΔD/Δt based on the command of the target weight reduction speed ΔDo/Δt. A command is sent to the electron beam control device 50 to control the power of the electron beam 52 so that Δt matches ΔDo/Δt, and the rate of weight decrease is constant (that is, ΔD
o/Δt).

Hereinafter, according to configuration E, the weight reduced by the evaporation of the vapor deposition material l is detected, and based on this, the power of the electron beam is controlled so as to keep the weight reduction rate, that is, the evaporation rate constant, so that the weight of the material is reduced. Even when not replenishing, the deposition material l
This makes it possible to deposit at a constant evaporation rate until almost all is removed.

All of the above has explained the monitoring and control of the weight of vapor deposition materials, but this is not limited to vapor deposition materials, and also includes monitoring and control as described in L when melting materials in processes such as melt processing of metals etc. It is also applicable to

Effects of the Invention The weight monitoring device for melting materials or sublimable materials of the present invention as set forth in claim 1 has the above-described configuration, and can directly monitor weight with high accuracy, and realizes highly practical weight monitoring with a long life. I can do it.

The present invention according to claim 2 has the above-mentioned configuration, which can eliminate errors in the weight detection means due to temperature rise, so that the weight of the molten material or sublimable material can be directly monitored with high precision, and it is practical with a long life. An excellent heavy IIk monitoring device can be provided.

The present invention as set forth in claim 4 is 2#: Since the structural acid can be made less susceptible to the weight and vibration of the pipe through which the cooling liquid flows, it is possible to directly measure the weight of the molten material or sublimable material with high precision. It is possible to provide a highly practical weight monitoring device that can monitor and has a long life.

The molten material or sublimable material weight m1ss device of the present invention according to claim 5 has the above-described configuration, and can directly monitor the weight of the material over a long period of time with high precision, and can also measure the weight while replenishing the material. Since the value can be controlled with high precision, production "C" can realize stable production with high yield over a long period of time.

The apparatus for controlling the weight of a molten material or a sublimable material according to the present invention according to claim 6 has the above-mentioned configuration, and is capable of directly monitoring the weight of the material over a long period of time with high precision, and adjusts the weight reduction rate of the material to a required value. Since the material can be controlled with high precision until it is almost completely eliminated, it is possible to improve the utilization efficiency of the material, and in production, it is possible to achieve stable production with a high yield.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of a molten material weight monitoring device in one embodiment of the present invention, and FIG. 2 is a partially sectional view schematically showing a molten material weight monitoring device in another embodiment of the present invention. FIG. 3 is a partially cutaway perspective view of a molten material weight control device in another embodiment of the present invention, and FIG. 4 is a partially cutaway perspective view of a molten material weight control device in another embodiment of the present invention. FIG. 5 is a sectional view of the weight detection section of the molten material weight monitoring device in the embodiment of the present invention shown in FIG. l... Vapor deposition material, 2... Holding means (container), 3...
・Hearth, 4... Weight detection means, 5... Beam, 7...
・Weight detection means, 8...insulation means, lO... flow path,
11a, 1)...Cooling vibrator, 12...Pressure fluctuation buffer, 13...Bubble trap, 30...Supporting means (
bearing is a stand), 31... hollow shaft, 40... supply material rod, 41... drive roller, 46... guide roller, 42
...Motor, 43...Motor control device, 45...
Weight control device, 50...Electronic bee 11 control device, 51
...Filament, 52...Electron beam, 53...
・Weight reduction speed control device.

Claims (6)

[Claims] (1) A holding means for accommodating and holding a molten material or a sublimable material, a weight detection means for detecting the total weight of the material and the holding means, and a weight detection means for detecting a change in the weight of the material from a change in the total weight. 1. A weight monitoring device for a molten material or a sublimable material, comprising a weight detecting means for detecting the weight. (2) A holding means for containing and holding a molten material or a sublimable material, a weight detection means for detecting the total weight of the material and the holding means, and a weight detection means for detecting a change in the weight of the material from a change in the total weight. A method of detecting a molten material or a sublimable material, comprising a weight detecting means for detecting the molten material or a sublimable material, and a heat insulating means provided between the molten material or the sublimable material and the weight detecting means, or between the weight detecting means. Weight monitoring device. (3) The heat insulating means includes a member having a flow path filled with a cooling liquid, a means for removing air bubbles contained in the cooling liquid, and a means for buffering pressure fluctuations of the cooling liquid. 3. A weight monitoring device for molten material or sublimable material according to claim 2. (4) a holding member that accommodates and holds a molten material or a sublimable material; a support means that rotatably supports the holding member; and detecting the rotational force of the holding member;
Weight sensing means for detecting the total weight of the molten material or sublimable material and the holding member containing the material; and the molten material or sublimable material and the weight sensing means; 1. A weight monitoring device for a molten material or a sublimable material, comprising a cooling liquid supplied using a structure. (5) a holding means for containing and holding a molten material or a sublimable material, a weight detection means for detecting the total weight of the material and the holding means, and a replenishing means for replenishing the material into the holding means; , a control means for controlling the replenishment means so that the weight of the material reaches a required value based on the weight signal of the material from the weight detection means. weight control device. (6) a holding means for storing and holding a molten material or a sublimable material, a heating means for heating and melting or sublimating the material, and a weight detection means for detecting the total weight of the material and the holding means; and a control means for controlling the heating means so that the weight reduction rate of the material reaches a desired value based on the weight signal of the material from the weight detection means. Material weight control device.