JP6026875B2 - Vaporization monitoring system and monitoring method for solid materials - Google Patents

Description

  The present invention relates to a solid material vaporization monitoring system and monitoring method, for example, a material gas used in a production apparatus or research facility such as a semiconductor or a solar cell using a solid material, or a special gas used in various processes. The present invention relates to a system and a monitoring method for monitoring the amount of vaporized or sublimated solid material in a gas supply apparatus such as the above. As used herein, the term “solid material” refers to a solid material that can be evaporated or sublimated (vaporized) / supplied by a carrier gas widely used industrially, for example, an inorganic metal compound such as hafnium chloride, Examples thereof include solid organometallic compounds such as trimethylindium, solid organic compounds such as pyromellitic dianhydride, anthraquinone and phthalic acid, and solid inorganic compounds such as aluminum chloride.

  Gas materials and liquid materials have been widely used as manufacturing equipment for producing semiconductors, solar cells, etc., research equipment for developing new materials, or semiconductor materials that require high-purity products (for example, film-forming materials). However, in recent years, the above solid materials evaporated or sublimated are often used with carrier gas. Such a solid material is supplied to a gas (hereinafter referred to as “solid component gas”) evaporated or sublimated and transported by an inert gas having low reactivity and high stability such as a rare gas such as helium or argon, and the above-described manufacturing apparatus. Being consumed.

  Such solid materials have problems such as a slower evaporation or sublimation rate than before, stable evaporation or sublimation is difficult and the amount of vaporization is not stable, and it is difficult to obtain a purified solid material and the solid component gas is limited. However, due to the expansion of the range of use and the advancement of related technologies, various studies have been made on the stable supply of solid material gas.

  For example, to provide a method and an apparatus for heating a solid material having a low thermal stability efficiently by sublimating and purifying a solid material having a low thermal stability while heating a minute amount of a large amount of feedstock uniformly and in a short time. For this purpose, a sublimation purification apparatus as shown in FIG. 4 has been proposed (see, for example, Patent Document 1). Specifically, one layer of the cylindrical metal material 102 of the sublimation part A is a magnetic metal material, and has an induction coil 103 that generates heat by electromagnetic induction on the outer periphery, and a temperature of the downstream side of the sublimation part. Collection sections B and C having a plurality of different zones are provided, and one zone has a cylindrical metal material made of a magnetic metal material, and has an induction coil 108 that generates heat by electromagnetic induction on the outer periphery. In addition, a temperature gradient is provided between the sublimation part and the collection part so that the temperature decreases substantially stepwise toward the downstream side. Here, 101 is a sublimation chamber, 104 and 109 are thermocouples, 105 and 110 are temperature controllers, 106 is a butterfly valve, 107 and 111 are cylindrical bodies, 112 is a trap, and 113 is a vacuum pump.

JP 2000-93701 A

However, in the above-described sublimation purification method, sublimation purification device, or solid material gas supply device or supply method, the following problems may occur.
(I) For uniform sublimation and supply of a solid material by a carrier gas, not only the control of the sublimation temperature as described above but also a powder or granule in the normal state. There were fluctuations in the amount of vaporization due to variations in evaporation or sublimation rate. As a result, in the actual supply of the solid material gas, it is difficult to ensure the stability of the supply component concentration (hereinafter referred to as “material concentration”) in the solid material gas.
(Ii) The remaining amount of the solid material not only greatly affects the material concentration, but also the shape and form of the solid material that changes depending on the use greatly affects the material concentration. In particular, in the case of powdered or granular solid materials, even if there is a predetermined remaining amount, it may not be possible to obtain a sufficient material concentration due to changes in the contact state with the carrier gas on the surface, etc. I understood.
(Iii) In addition, in the manufacturing process of semiconductors and the like as described above in which a solid material gas supply device is installed, since the material concentration has a great influence on the final product, it is necessary to manage the material concentration in-line. The detection of material concentration requires very high accuracy, reliability and stability.

  An object of the present invention is to provide a solid material vaporization monitoring system and a monitoring method capable of detecting a material concentration with high accuracy, reliability, and stability with a simple method and configuration in a solid material gas supply apparatus. There is. Another object of the present invention is to provide a solid material gas supply device that can use these to supply a solid material gas at a stable concentration.

  As a result of intensive studies to solve the above problems, the present inventors can achieve the above object by the following solid material vaporization monitoring system, monitoring method, and solid material gas supply device using them. As a result, the present invention has been completed.

The present invention is a solid material vaporization monitoring system comprising:
A container having a predetermined capacity capable of being heated, in which a solid material is disposed, a carrier gas supply unit that is responsible for supplying carrier gas to the container, and a solid that is responsible for delivering the solid material gas accompanying the solid material from the container In the solid material gas supplied from the material gas supply part, the pressure reduction processing part for degassing the inside of the container to make the pressure reduced, the pressure detector for detecting the pressure inside the container, and the solid material gas supply part A concentration detector that detects a supply component concentration, and an arithmetic unit that receives at least outputs from the pressure detector and the concentration detector and performs arithmetic processing;
The container in a heated state in which a vapor pressure of a gas component evaporated or sublimated from a solid material in the container previously heated to a predetermined temperature under a reduced pressure condition is detected by the pressure detector and a carrier gas having a predetermined flow rate is introduced. The concentration of the supply component in the solid material gas delivered from is detected by a concentration detector, and the vaporization amount of the solid material is calculated from the vapor pressure and the flow rate of the carrier gas based on the following formula 1.
Vaporization amount of solid material = (saturated vapor pressure / total pressure of solid material) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
A correlation between the pressure in the container under the predetermined container temperature and the predetermined carrier gas flow rate, the concentration of the supply component, and the vaporization amount of the solid material is set in advance.
In the supply state of the solid material gas in which the carrier gas is supplied to the container heated to a predetermined temperature, the vaporization amount of the solid material is calculated from the detected pressure in the container and the detected concentration of the supply component. It is characterized by that.

Supplying the solid material gas by evaporating or sublimating the solid material has some problems such as the stability of the material concentration as described above. In the present invention, in the supply of a solid material gas by sublimation of a solid material, the correlation between the vaporization amount and factors that affect the vaporization amount of the solid material in advance (variable factors such as the temperature / pressure in the container and the flow rate of the carrier gas) The amount of vaporization of the solid material can be monitored with high accuracy by calculating the amount of vaporization based on the concentration (material concentration) of the supply component in the solid material gas having a high correlation with the amount of vaporization. It has been found that these problems can be solved. In other words, the physical quantity, which is difficult to monitor stably, such as the amount of vaporization, can be obtained more accurately by using the above-mentioned fluctuation factors that cause the fluctuation and the material concentration as a result of the fluctuation as an index. Specifically, the solid material is evaporated or sublimated under stable specific conditions including the reference decompression condition in advance, and the correlation between the above-mentioned variation factor and the material concentration at that time is obtained, and based on the set conditions, A highly reliable vaporization amount can be obtained by calculating the vaporization amount using a variable element under dynamic conditions as an index. As described above, it is possible to provide a vaporization amount monitoring system for a solid material that can detect a material concentration with high accuracy, reliability, and stability with a simple method and configuration. Also, by using this system, it has become possible to configure a solid material gas supply device that can supply solid material gas at a stable concentration.
Here, the concentration of the supply component in the solid material gas and the flow rate of the carrier gas are monitored, and based on the relationship between the remaining amount of the solid sample obtained in advance and the concentration of the supply component in the solid material gas, It is preferable to manage the remaining amount. The remaining amount of the solid material S becomes a predetermined amount or less, so that not only the total amount of the solidified vaporized material but also the remaining amount itself and the shape, form, etc. (properties) of the solid material S do not cause a decrease in the material concentration. In addition, the solid material gas G having a stable material concentration can be supplied by adjusting the flow rate of the carrier gas C using the obtained remaining amount information of the solid sample S.

The present invention is a system for monitoring the amount of vaporization of the solid material, wherein the concentration detector has two identical configurations of a sample cell through which the solid material gas flows and a comparison cell through which only the carrier gas flows. The solid material gas and the carrier gas are circulated under substantially the same pressure and the same flow rate conditions.
In general, a solid material has many substances having a large molecular weight, and an inert gas such as helium or nitrogen having a small molecular weight is often used as a carrier gas necessary for accompanying the substance. In other words, it is preferable to use a thermal conductivity detector (hereinafter also referred to as “TCD”) in detecting the material concentration. In order to monitor the amount of vaporization of various solid materials, it is preferable to eliminate the influence of the physical properties of the carrier gas. Among the TCDs, the solid material gas and the carrier gas are simultaneously measured, and the difference between them is detected. A comparative TCD that can be used is preferred. The present invention further improves the accuracy of TCD detection by making the above-mentioned variable factors affecting the vaporization amount substantially the same conditions, and also when the TCD is used in-line with the solid material gas supply device. It is possible to ensure the detection of the material concentration with high accuracy, reliability, and stability without affecting the characteristics of the supply device.
Here, the carrier gas first introduced and delivered to the comparison cell is introduced into the container and introduced into the sample cell as a solid material gas accompanied by the supply component, whereby the solid material gas and the carrier are introduced. It is preferable to detect the difference in the thermal conductivity of the gas. The carrier gas used can be reduced.

Moreover, this invention is a monitoring method using the vaporization amount monitoring system of the said solid material, Comprising: It has the following preliminary | backup process (1)-(7) and actual operation process (8)-(10). Features.
(1) A step of disposing a powdery or granular solid material in a container having a predetermined capacity (2) The container is sealed, the inside of the container is evacuated to a reduced pressure state, and heated to a predetermined temperature Step (3) Detecting the pressure in the container and waiting for the vapor pressure to rise and stabilize due to evaporation or sublimation of the solid material (4) Introducing a predetermined flow rate of carrier gas into the container and entraining the solid material (5) The step of detecting the concentration of the supply component in the supplied solid material gas (6) From the stable vapor pressure and the flow rate of the carrier gas, the solid material gas is discharged based on the following formula 1. Step of calculating vaporization amount Vaporization amount of solid material = (saturated vapor pressure of solid material / total pressure) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
(7) Based on the results of (1) to (6) above, the correlation between the pressure in the container under the predetermined temperature in the container and the predetermined carrier gas flow rate, the concentration of the supply component, and the vaporization amount of the solid material is obtained. Step (8) Step (9) where carrier gas is supplied continuously or discontinuously to the container heated to a predetermined temperature (9) Pressure in the container and concentration of supply components in the solid material gas Detecting (10) calculating the vaporization amount of the solid material from the correlation set in the step ( 7 ) based on the pressure in the container and the concentration of the supply component

As described above, the solid material is vaporized or sublimated under stable specific conditions including the reference decompression condition in advance, and the correlation between the above-mentioned variable element and the material concentration at that time is obtained, and based on the set conditions. A highly reliable vaporization amount can be obtained by calculating the vaporization amount using a variable element under dynamic conditions as an index. The present invention realizes such a function by a two-stage operation of a preliminary process and an actual operation process, and provides a method for monitoring a vaporization amount of a solid material that can detect a material concentration with high accuracy, reliability, and high stability. It became possible to provide.
Furthermore, after the above steps (7) and (10),
(7-2) The process of calculating | requiring the relationship between the residual amount of the solid material in the said container, and the density | concentration of the supply component in solid material gas.
(11) The concentration of the supply component in the solid material gas and the flow rate of the carrier gas are monitored, and based on the relationship between the remaining amount of the solid sample obtained in advance and the concentration of the supply component in the solid material gas, Process for managing remaining amount
It is preferable to add. The remaining amount of the solid material S becomes a predetermined amount or less, so that not only the total amount of the solidified vaporized material but also the remaining amount itself and the shape, form, etc. (properties) of the solid material S do not cause a decrease in the material concentration. In addition, the solid material gas G having a stable material concentration can be supplied by adjusting the flow rate of the carrier gas C using the obtained remaining amount information of the solid sample S.

Schematic showing a basic configuration example of a solid material vaporization monitoring system according to the present invention Schematic which shows the 2nd, 3rd structural example of the vaporization amount monitoring system of the solid material which concerns on this invention Explanatory diagram illustrating the dependence of the vaporization amount of the solid material on the flow rate of the carrier gas Schematic illustrating a sublimation purification apparatus according to the prior art

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a solid material vaporization amount monitoring system according to the present invention (hereinafter referred to as “the present system”) and a solid material vaporization amount monitoring method (hereinafter referred to as “the present method”) using the same will be described with reference to the drawings While explaining. The system includes a container in which a solid material is disposed, a carrier gas supply unit, a solid material gas supply unit, a decompression processing unit that depressurizes the interior of the container, and a pressure detector that detects the pressure inside the container. A concentration detector that detects a supply component concentration (material concentration) in the solid material gas, and an arithmetic unit that receives at least outputs from the pressure detector and the concentration detector and performs arithmetic processing. Solid material gas delivered from a heated container in which a carrier gas having a predetermined flow rate is introduced by detecting the vapor pressure of a gas component evaporated or sublimated from the solid material in the container previously heated to a predetermined temperature under a reduced pressure condition The material concentration in the container is detected, the vaporization amount of the solid material is calculated from the vapor pressure and the flow rate of the carrier gas, and the pressure-supply component in the container under the predetermined container gas temperature and the predetermined carrier gas flow rate conditions in advance. The correlation between the concentration and the vaporization amount of the solid material is set, and in the supply state of the solid material gas in which the carrier gas is supplied to the container heated to a predetermined temperature, the detected pressure in the container and the detected material concentration The amount of vaporization of the solid material is calculated. Thereby, it is possible to monitor the vaporization amount of the solid material with high accuracy, reliability and stability with a simple method and configuration.

<Example of basic configuration of this system>
FIG. 1 is a schematic diagram showing a basic configuration example (first configuration example) of the system. This system includes a container 1 having a predetermined heatable capacity in which a solid material S is disposed, a carrier gas supply unit having on-off valves V1 and V2 that are responsible for supplying the carrier gas C to the container 1 and a flow rate control unit 2. And a solid material gas supply part for supplying the solid material gas G accompanied by the solid material S via the on-off valve Vs, and the inside of the container 1 is deaerated by the decompression pump 3 via the on-off valve V3. A pressure reducing unit 4 for detecting the pressure inside the container 1, and a concentration detector 5 for detecting the concentration (material concentration) of the supply component in the solid material gas G supplied from the solid material gas supply unit. And an arithmetic unit 6 that receives at least outputs from the pressure detector 4 and the concentration detector 5 and performs arithmetic processing. The solid material gas G delivered from this system is supplied to a consumption facility 10 such as a semiconductor manufacturing facility.

The “solid material” as used herein refers to a solid material that is vaporized (evaporated or sublimated) at a predetermined temperature widely used industrially as described above. Specifically, for example, hafnium chloride (HfCL ₄ ). And inorganic metal compounds such as zirconium chloride (ZrCL ₄ ), solid organometallic compounds such as trimethylindium ((CH ₃ ) ₃ In), biscyclopentadienyl magnesium (MgH ₂ [(CH ₂ ) ₅ ] ₂ ), pyro Mellitic dianhydride (hereinafter sometimes referred to as “PMDA”), anthraquinone, solid organic compounds such as phthalic acid (C ₆ H ₄ (COOH) ₂ ), naphthalene (C ₁₀ H ₈ ), or aluminum chloride (AlCl ₃₎ ) And the like. In general, in addition to solid materials at normal temperature (20 to 30 ° C.) and normal pressure (about 0.1 MPa), here, solid materials are also widely included under pressure or low temperature conditions. Table 1 below illustrates the solid material, the melting point, the set temperature, and the vapor pressure at that time. Of course, it is not limited to these substances and setting conditions.

In this system, the vapor pressure of the gas component evaporated or sublimated from the solid material S in the container 1 previously heated to a predetermined temperature under a reduced pressure condition is detected by the pressure detector 4, and a carrier gas C having a predetermined flow rate is introduced. The concentration (material concentration) of the supply component in the solid material gas delivered from the heated container 1 is detected by the concentration detector 5, and based on the following equation 1 from the vapor pressure and the flow rate of the carrier gas C by the calculation unit 6. While calculating the vaporization amount of the solid material,
Vaporization amount of solid material = (saturated vapor pressure / total pressure of solid material) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
The correlation between the pressure in the container 1, the concentration of the supply component, and the vaporization amount of the solid material under a predetermined temperature in the container 1 and a predetermined flow rate of the carrier gas C is preset. Here, the total pressure refers to the pressure in the container 1 when the carrier gas C is introduced into the container 1, and is the supply pressure of the solid material gas G. By calculating the vaporization amount of the solid material under the reduced pressure condition, the calculation standard of the vaporization amount of the solid material in the supply state of the solid material gas G can be clarified.

  In the supply state of the solid material gas in which the carrier gas C is supplied to the container 1 heated to a predetermined temperature during actual operation, the correlation between the set pressure in the container 1, the concentration of the supply component, and the vaporization amount of the solid material is obtained. From the detected pressure in the container 1 and the detected concentration of the supply component, the calculation unit 6 can calculate the vaporization amount of the solid material. Based on the vaporization amount of the solid material under the above-described reduced pressure condition, the vaporization amount of the solid material can be monitored with higher accuracy.

  It is preferable that the container 1 is provided with a heating unit 1a for heating from the outside. As shown in Table 1 above, by heating to a set temperature corresponding to the characteristics of each solid sample S, vaporization of the solid sample S is promoted, and a solid material gas G having a predetermined material concentration can be supplied. The vaporization of the solid sample S is carried out with the carrier gas C both when heated above the melting point and evaporated again in the liquefied state, when heated below the melting point and evaporated or sublimated in the solid state. Therefore, it can be performed stably.

  The remaining amount of the solid sample S in the container 1 is preferably monitored. Knowledge that if the remaining amount of the solid material S is less than or equal to the predetermined amount, the concentration of the solid material S may be reduced depending on not only the total amount of the vaporized solid material but also the remaining amount itself and the shape and form of the solid material S (properties). In addition, the material concentration in the solid material gas G and the flow rate of the carrier gas C are monitored, and based on the relationship between the remaining amount of the solid sample S and the material concentration in the solid material gas G determined in advance, The remaining amount of solid material can be managed. Further, by adjusting the flow rate of the carrier gas C using the obtained remaining amount information of the solid sample S, the solid material gas G having a stable material concentration can be supplied. That is, when the monitored remaining amount in the container 1 is smaller than the set amount and a predetermined time is required until refilling, the predetermined material concentration is reduced by decreasing the flow rate of the entire carrier gas C. Can be secured. The flow rate of the carrier gas C can be adjusted by the flow rate control unit 2.

  The concentration detector 5 is preferably a detector using a measurement principle having selectivity for the solid material S. Specifically, a detector utilizing differences in physical characteristics between the carrier gas C and the solid material S, for example, thermal conductivity, light absorption characteristics such as an ultraviolet region, an infrared region, or a microwave can be mentioned. . In addition, when a thermal conductivity detector (TCD) is used as the concentration detector 5, high accuracy and stable measurement can be performed even under reduced pressure conditions.

  The carrier gas C is preferably a gas having low reactivity and high stability. For example, a rare gas such as helium or argon or a nitrogen gas can be used. When TCD is used as the concentration detector 5, a carrier gas S having a low thermal conductivity is preferable, and nitrogen gas or helium gas is preferable. In general, the thermal conductivity of the solid material S having a large number of substances having a large molecular weight is large, and by utilizing the difference, stable detection of the material concentration can be performed. Here, for the detection of the material concentration, it is preferable to obtain in advance a rise characteristic with respect to the pulse response of the concentration detector 5 from the supply of the carrier gas C, and to use the peak value as the detection value. Ideally, the detected value is preferably a value when the supply component vaporized from the solid material S is continuously entrained with a small flow rate of the carrier gas C, and the peak value corresponds to this.

<Vaporization monitoring method for solid materials using this system>
Next, as a method for monitoring the amount of vaporization of the solid material S using this system (this method), a process of introducing the carrier gas C into the system and taking out the solid material gas G having a predetermined material concentration will be described in detail. It has the following preliminary steps (1) to (7) and actual operation steps (8) to (10).

[Preliminary process]
The preliminary process includes the following processes.
(1) A step of disposing a powdery or granular solid material in a container having a predetermined capacity (2) The container is sealed, the inside of the container is evacuated to a reduced pressure state, and heated to a predetermined temperature Step (3) Detecting the pressure in the container and waiting for the vapor pressure to rise and stabilize due to evaporation or sublimation of the solid material (4) Introducing a predetermined flow rate of carrier gas into the container and entraining the solid material (5) The step of detecting the concentration of the supply component in the supplied solid material gas (6) From the stable vapor pressure and the flow rate of the carrier gas, the solid material gas is discharged based on the following formula 1. Step of calculating vaporization amount Vaporization amount of solid material = (saturated vapor pressure of solid material / total pressure) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
(7) Based on the results of (1) to (6) above, the correlation between the pressure in the container under the predetermined temperature in the container and the predetermined carrier gas flow rate, the concentration of the supply component, and the vaporization amount of the solid material is obtained. Process to set

(1) Step of Disposing Solid Material in Container As a normal state, a predetermined amount of powdery or granular solid material S is prepared. In the case of an irregular granular solid material S, it is preferably pulverized into powder or granules. In the case of the solid material S having reactivity, the following operation is performed in an inert gas atmosphere. Next, the solid material S is installed in the container 1. When a large surface area can be obtained, the solid material S is preferably molded. Stable vaporization conditions can be ensured. When a binder is required for molding, a predetermined amount of binder is prepared in advance, put into a tray, and mixed with a solid material for molding.

(2) Step of bringing the inside of the container to a predetermined temperature in a decompressed state The container 1 is sealed with the on-off valves V2 and Vs closed, the on-off valve V3 is opened and the decompression pump 3 is operated to deaerate the inside of the container 1 The pressure is reduced. The degree of decompression (internal pressure of the container 1) is detected by the pressure detector 4. In the normal temperature state, the vaporization from the solid material S hardly occurs, and the pressure can be reduced to the limit pressure of the pressure reducing pump 3. If the internal pressure of the container 1 is stabilized in a reduced pressure state, the container 1 is heated to the set temperature exemplified in Table 1 above, for example, according to the type of the solid material S.

(3) Step of stabilizing the pressure in the container is heated to a set temperature corresponding to the solid sample S, and becomes a vapor pressure of a desired solid material component. Since the vapor pressure rises due to vaporization of the solid material S due to heating, the pressure in the container 1 is detected by the pressure detector 4 and waits for its stability. Although the stabilization time varies depending on the capacity of the container 1 and the filling amount and properties of the solid material S, in this method, when the rate of increase per unit time is within a predetermined value for the detected pressure value, To do.

(4) Carrier gas supply and solid material gas supply step With the solid sample S installed, the carrier gas C is introduced into the container 1 via the on-off valve V1 and the flow rate controller 2. The pressure and flow rate of the carrier gas C are adjusted to a desired set value by the flow rate control unit 2. The carrier gas C is accompanied by a solid material having a saturated vapor pressure in the container 1 and is supplied as a solid material gas G through the on-off valve V2. Vaporization of the solid sample S should be accompanied by a carrier gas when heated above the melting point and evaporated again in the liquefied state or heated below the melting point and evaporated or sublimated in the solid state. Therefore, it can be performed stably. By setting the flow rate of the carrier gas C and the volume of the container 1 in advance so as to obtain a desired space velocity, a sufficient contact time can be secured and a solid material gas G having a stable material concentration can be obtained. The pressure in the container 1 at this time is detected by the pressure detector 4. As the solid material gas G is produced, the solid sample S is reduced from the upper surface of the solid sample S. The decrease in the solid sample S can be grasped by visual monitoring through a monitoring window or monitoring by optical sensor output (not shown). The decrease in the material concentration accompanying the decrease in the solid sample S can be prevented by installing a predetermined amount or more of the solid sample S.

(5) Step of detecting material concentration The concentration detector 5 detects the concentration (material concentration) of the supply component in the solid material gas G delivered from the container 1 via the on-off valve Vs. When TCD is used as the concentration detector 5, it is possible to detect the material concentration with high accuracy even under reduced pressure conditions.

(6) Step of calculating the vaporization amount of the solid material From the vapor pressure detected in the above (3) and the flow rate of the carrier gas C detected in the above (4) and the pressure in the container 1 Based on Equation 1, the amount of vaporization of the solid material is calculated.
Vaporization amount of solid material = (saturated vapor pressure / total pressure of solid material) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
Here, the total pressure refers to the pressure in the container 1 when the carrier gas C is introduced into the container 1, and is the supply pressure of the solid material gas G.

(7) Step of presetting correlation between pressure in container-concentration of supply component-vaporization amount of solid material Pressure in container 1 detected in (4) above, supply component detected in (5) above From the concentration (material concentration) and the vaporization amount of the solid material obtained in (6) above, “pressure in the container−concentration of supply component−concentration of the solid material under a predetermined temperature in the container and a predetermined carrier gas flow rate condition” Set the correlation of “vaporization amount”.

[Production process]
The actual operation process in this method has the following processes based on the results of (1) to (7) above.
(8) A step in which a carrier gas is supplied continuously or discontinuously to the container heated to a predetermined temperature. (9) A step of detecting the pressure in the container and the concentration of supply components in the solid material gas. (10) A step of calculating the vaporization amount of the solid material from the correlation set in the step ( 7 ) based on the pressure in the container and the concentration of the supply component

(8) Step of supplying carrier gas Carrier gas C adjusted to a predetermined pressure and flow rate is continuously or non-continuously supplied to container 1 heated to a predetermined temperature, and vaporized from solid material S. The supplied components in the solid material are accompanied and delivered from the container 1. The pressure when the carrier gas C is supplied is detected by the pressure detector 4.

(9) Step of detecting the pressure in the container and the material concentration In the above (8), the pressure in the container 1 and the concentration of the supply component in the solid material gas (material concentration) in the state where the carrier gas C is supplied are detected. At this time, by detecting under the same conditions as in the above (5), it can be made the same as the calculation standard of the vaporization amount obtained in the preliminary process, and more accurate conversion can be performed.

(10) Step of calculating vaporization amount of solid material Based on the pressure in the container 1 detected in (8) above and the concentration of the supply component detected in (9) above by the calculation unit 6, the above steps ( 7 ) The vaporization amount of the solid material is calculated from the correlation set in step 7 ). Thereby, the vaporization amount of the solid material delivered from the system by the present method can be monitored continuously or discontinuously such as in batch mode.

<Other configuration examples of this system>
2A and 2B are schematic views showing a second configuration example of the present system. In the second configuration example, the concentration detector 5 includes a cell portion (not shown) having two identical configurations of a sample cell through which the solid material gas G flows and a comparison cell through which only the carrier gas C flows. A solid state gas G and a carrier gas C are circulated under substantially the same pressure and the same flow rate condition using a degree detector (hereinafter referred to as “R-TCD”). By using the R-TCD that measures the solid material gas G and the carrier gas C at the same time and detects the difference between them, the influence of the physical properties of the carrier gas C is eliminated, and the variation factors affecting the vaporization amount are substantially the same. By setting the conditions, the detection accuracy of the thermal conductivity of the supply component in the solid material gas G can be increased.

Specifically, as illustrated in FIG. 2A, the supply flow path of the carrier gas C is branched, and one is introduced into the R-TCD comparison cell via the on-off valve V4 (comparison gas), and the other Is introduced into the container 1 through the on-off valve V2. The carrier gas C introduced into the container 1 is accompanied by a supply component vaporized from the solid material S and then introduced into the sample cell of the R-TCD as a solid material gas G through the on-off valve Vs (sample gas). The difference in thermal conductivity between the solid material gas G and the carrier gas C can be detected, and the detection can be performed with high accuracy from which the fluctuation factors such as the flow rate fluctuation and the base gas composition fluctuation are eliminated.

In this case, as illustrated in FIG. 2 (B), without branching the supply channel of the carrier gas C, first the carrier gas C which has been introduced dispensing the reference cell of the R-TCD, the opening and closing valve V2 Into the container 1 (comparative gas). The carrier gas C introduced into the container 1 is accompanied by a supply component vaporized from the solid material S and then introduced into the sample cell of the R-TCD as a solid material gas G through the on-off valve Vs (sample gas). The difference in thermal conductivity between the solid material gas G and the carrier gas C can be detected. The carrier gas used can be reduced. In addition, when it is not necessary to use the carrier gas C as the reference gas as the total amount of the sample gas, when a part of the reference gas is used as the sample gas and the flow rate of the sample gas is larger than the flow rate of the comparative gas, A configuration in which a new carrier gas C is added as a sample gas is also possible.

<Verification of the system and method>
Using pyromellitic dianhydride (PMDA) and anthraquinone as the solid material S, the function of this system or this method was verified as follows.

(I) Verification condition (i-1) About 70 g of powdery PMDA is filled in the container 1, the inside of the container 1 is brought into a reduced pressure state (vacuum state), and heated to a set temperature of 259 ° C. A stable pressure was detected by the pressure detector 4. Next, a carrier gas C (nitrogen) having a constant flow rate (50 sccm) is introduced into the container 1 heated to a set temperature of 259 ° C., and delivered through the TCD 5 heated to substantially the same temperature. The amount of PMDA vaporization was calculated from the output of TCD5 at this time. Further, the flow rate of the carrier gas C was varied, and the vaporization amount of PMDA was calculated from the output of TCD5.
(I-2) Under the same conditions as (i-1) above, the set temperature was changed to 250 ° C., and the same verification was performed.
(I-3) The solid material S was replaced with anthraquinone, filled with about 70 g of anthraquinone, the inside of the container 1 was put under reduced pressure, heated to a set temperature of 250 ° C., and a stable pressure was detected by the pressure detector 4. Next, a carrier gas C (nitrogen) having a constant flow rate (50 sccm) is introduced into the container 1 heated to a set temperature of 250 ° C., and anthraquinone in the solid material gas G delivered from the container is detected by TCD5. . The vaporization amount of anthraquinone was calculated from the output of TCD5 at this time.

(Ii) Verification result (ii-1) The vapor pressure at a preset temperature of 259 ° C. of PMDA obtained in advance was 7 Torr. The pressure in the container 1 at the time of supplying the carrier gas C is 50 Torr. The vaporization amount is calculated from the carrier gas flow rate (50 sccm) and the PMDA molecular weight (218 g / mol). 0.068 g / min was obtained. The output of TCD at this time was 0.12V.
(7/50) × (0.05 / 22.4) × 218 = 0.068 g / min (Equation 2)
Here, “22.4” indicates the volume of 1 mol of the ideal gas converted into the standard state.
Further, the vaporization amount of PMDA at each flow rate was converted from the TCD value when the flow rate of the carrier gas C was changed under these conditions, and the result as shown in FIG. 3 was obtained. In the measurement range, a result that fluctuated substantially linearly was obtained.
(Ii-2) At a set temperature of 250 ° C., the vapor pressure of PMDA was 5 Torr. The vaporization amount was calculated from the carrier gas flow rate (50 sccm) and the PMDA molecular weight (218 g / mol), and the vaporization amount of 0.048 g / min was obtained from Equation 3 below. The output of TCD at this time was 0.10V.
(5 /50)×(0.05/22.4)×218= 0.048 g / min ·· ( Equation 3)
(Ii-3) At a set temperature of 250 ° C., the vapor pressure of anthraquinone was 15 Torr. The vaporization amount was calculated from the carrier gas flow rate (50 sccm) and the molecular weight of anthraquinone (208 g / mol), and the vaporization amount of 0.14 g / min was obtained from Equation 4 below. The output of TCD at this time was 0.08V.
(15/50) × (0.05 / 22.4) × 208 = 0.14 g / min (Equation 4)

(Iii) Summary According to the present system and method, even if the solid material changes, if the vapor pressure and the material concentration at the set temperature are detected in advance, the vaporization of each individual material can be performed by the same system without changing the equipment. It has been demonstrated that the amount can be accurately monitored.

DESCRIPTION OF SYMBOLS 1 Container 1a Heating part 2 Flow control part 3 Pressure reducing pump 4 Pressure detector 5 Concentration detector 6 Calculation part 10 Consumption equipment C Carrier gas G Solid material gas S Solid material V1, V2, V3, Vs On-off valve

Claims (3)

A container having a predetermined capacity capable of being heated, in which a solid material is disposed, a carrier gas supply unit that is responsible for supplying carrier gas to the container, and a solid that is responsible for delivering the solid material gas accompanying the solid material from the container In the solid material gas supplied from the material gas supply part, the pressure reduction processing part for degassing the inside of the container to make the pressure reduced, the pressure detector for detecting the pressure inside the container, and the solid material gas supply part A concentration detector that detects a supply component concentration, and an arithmetic unit that receives at least outputs from the pressure detector and the concentration detector and performs arithmetic processing;
The container in a heated state in which a vapor pressure of a gas component evaporated or sublimated from a solid material in the container previously heated to a predetermined temperature under a reduced pressure condition is detected by the pressure detector and a carrier gas having a predetermined flow rate is introduced. The concentration of the supply component in the solid material gas delivered from is detected by a concentration detector, and the vaporization amount of the solid material is calculated from the vapor pressure and the flow rate of the carrier gas based on the following formula 1.
Vaporization amount of solid material = (saturated vapor pressure / total pressure of solid material) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
A correlation between the pressure in the container under the predetermined container temperature and the predetermined carrier gas flow rate, the concentration of the supply component, and the vaporization amount of the solid material is set in advance.
In the supply condition of the solid material gas carrier gas is supplied to the vessel is heated to a predetermined temperature to calculate the vaporization amount of the solid material from the density of the feed components detected pressure of the detected said vessel ,
As the concentration detector, a thermal conductivity detector having a cell portion having two identical configurations of a sample cell through which the solid material gas flows and a comparison cell through which only the carrier gas flows is used. The carrier gas is circulated under substantially the same pressure and the same flow rate, and the carrier gas first introduced and supplied to the comparison cell is introduced into the container, and the sample is used as a solid material gas accompanied by the supply components. A vaporization amount monitoring system for a solid material , wherein a difference in thermal conductivity between the solid material gas and the carrier gas is detected by being introduced into a cell . A container having a predetermined capacity capable of being heated, in which a solid material is disposed, a carrier gas supply unit that is responsible for supplying carrier gas to the container, and a solid that is responsible for delivering the solid material gas accompanying the solid material from the container In the solid material gas supplied from the material gas supply part, the pressure reduction processing part for degassing the inside of the container to make the pressure reduced, the pressure detector for detecting the pressure inside the container, and the solid material gas supply part A concentration detector that detects a supply component concentration, and an arithmetic unit that receives at least outputs from the pressure detector and the concentration detector and performs arithmetic processing;
The container in a heated state in which a vapor pressure of a gas component evaporated or sublimated from a solid material in the container previously heated to a predetermined temperature under a reduced pressure condition is detected by the pressure detector and a carrier gas having a predetermined flow rate is introduced. The concentration of the supply component in the solid material gas delivered from is detected by a concentration detector, and the vaporization amount of the solid material is calculated from the vapor pressure and the flow rate of the carrier gas based on the following formula 1.
Vaporization amount of solid material = (saturated vapor pressure / total pressure of solid material) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
A correlation between the pressure in the container under the predetermined container temperature and the predetermined carrier gas flow rate, the concentration of the supply component, and the vaporization amount of the solid material is set in advance.
In the supply state of the solid material gas in which the carrier gas is supplied to the container heated to a predetermined temperature, the vaporization amount of the solid material is calculated from the detected pressure in the container and the detected concentration of the supply component. ,
The concentration of the supply component in the solid material gas and the flow rate of the carrier gas are monitored, and the remaining amount of the solid material is determined based on the relationship between the remaining amount of the solid sample obtained in advance and the concentration of the supply component in the solid material gas. A solid material vaporization monitoring system characterized by management . A solid material comprising the following preliminary steps (1) to (7-2) and actual operation steps (8) to (11) using the solid material vaporization amount monitoring system according to claim 1 or 2. A method for monitoring the amount of vaporization of materials.
(1) A step of disposing a powdery or granular solid material in a container having a predetermined capacity (2) The container is sealed, the inside of the container is evacuated to a reduced pressure state, and heated to a predetermined temperature Step (3) Detecting the pressure in the container and waiting for the vapor pressure to rise and stabilize due to evaporation or sublimation of the solid material (4) Introducing a predetermined flow rate of carrier gas into the container and entraining the solid material (5) The step of detecting the concentration of the supply component in the supplied solid material gas (6) From the stable vapor pressure and the flow rate of the carrier gas, the solid material gas is discharged based on the following formula 1. Step of calculating vaporization amount Vaporization amount of solid material = (saturated vapor pressure of solid material / total pressure) × (flow rate of carrier gas) × (molecular weight of solid material) Equation 1
(7) Based on the results of (1) to (6) above, the correlation between the pressure in the container under the predetermined temperature in the container and the predetermined carrier gas flow rate, the concentration of the supply component, and the vaporization amount of the solid material is obtained. Process to set
(7-2) A step of determining the relationship between the remaining amount of the solid material in the container and the concentration of the supply component in the solid material gas (8) The carrier gas is continuously or non-circulated in the container heated to a predetermined temperature. A step of continuously supplying (9) a step of detecting the pressure in the vessel and the concentration of the supply component in the solid material gas (10) the above step based on the pressure in the vessel and the concentration of the supply component The step of calculating the vaporization amount of the solid material from the correlation set in ( 7 )
(11) The concentration of the supply component in the solid material gas and the flow rate of the carrier gas are monitored, and based on the relationship between the remaining amount of the solid sample obtained in advance and the concentration of the supply component in the solid material gas, Process for managing remaining amount

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