Semiconductor material gas supply device

Abstract

To provide a semiconductor material gas supply device for enabling the confirmation of the remaining amount of liquid metal without taking out a storage part of the liquid metal as a raw material for producing semiconductor material gas.SOLUTION: A semiconductor material gas supply device is selected which includes a first reaction container 1 for storing liquid metal M in the lower part of an internal space 1z, and a remaining amount confirmation mechanism 200 for confirming the remaining amount of the liquid metal M existing in the internal space 1z, the remaining amount confirmation mechanism 200 having electrodes 201, 202 located in the internal space 1z, and a current detection circuit 203 connected to the electrodes 201, 202.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a semiconductor material gas supply device.

Background Art

[0002] As next-generation power device materials, wide-bandgap semiconductors such as GaN, AlN, and Ga2O3 have attracted attention. In addition, GaAs-based semiconductors have attracted attention as materials for high-performance solar cells compared to Si.

[0003] As one of the methods for forming these semiconductor crystals, the halide or hydride vapor phase epitaxy (HVPE method) is known. This method is a method of forming a semiconductor crystal by reacting a metal halide with a Group V raw material such as ammonia or a Group VI raw material such as oxygen. The formation of a semiconductor crystal using the HVPE method has been actively studied because of its high growth rate and the ability to produce a high-purity film.

[0004] Patent Document 1 discloses a semiconductor material gas supply device including a gas-liquid reaction chamber that contains gallium as a molten metal at the lower part of an internal space, supplies a mixed gas containing at least one of chlorine gas and hydrogen chloride gas as a raw material gas at the upper part of the internal space, generates a product gas (gallium monochloride gas) by a gas-liquid reaction between the raw material gas and the molten metal, and discharges the mixed gas containing the product gas from the internal space.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the semiconductor material gas supply device disclosed in Patent Document 1, the raw material metal (liquid Ga) inside is consumed, and it is necessary to replenish the raw material metal when it falls below a certain amount. However, the gas-liquid reaction chamber that stores the raw material metal is surrounded by heaters and piping, making it difficult to visually check the amount of raw material remaining inside from the outside.

[0007] Furthermore, graphite is preferably used for the gas-liquid reaction chamber that stores the raw material metals, due to its corrosion resistance and ease of processing. In this way, when the raw material storage section is made of an opaque material such as graphite, it becomes more difficult to visually check the amount of raw material remaining inside from the outside without disassembling the device. In addition, if the raw material storage section is removed to check the remaining amount, it is necessary to interrupt the supply of semiconductor materials, and in order to restore it, heating of the raw materials and replacement with high-purity nitrogen gas to remove impurities are required.

[0008] The present invention has been made in view of the above circumstances, and aims to provide a semiconductor material gas supply device that allows confirmation of the remaining amount of liquid metal without removing the liquid metal storage unit, which is the raw material for generating semiconductor material gases. [Means for solving the problem]

[0009] To solve the above problems, the present invention has the following configuration. [1] A semiconductor material gas supply device that uses liquid metal as a raw material for semiconductor material gas generation, A first reaction vessel containing the liquid metal in the lower part of its internal space and supplied with a raw material gas to the upper part of its internal space, The system includes a remaining amount confirmation mechanism for confirming the remaining amount of the liquid metal present in the internal space, The aforementioned remaining amount confirmation mechanism One or more electrodes located in the internal space, A semiconductor material gas supply device having an electrometer circuit connected to the electrode. [2] The first reaction vessel has at least a bottom and side walls, The semiconductor material gas supply device according to [1], wherein the material of the bottom and the side wall is a conductor. [3] The semiconductor material gas supply apparatus according to [2], wherein the electrode and the side wall are electrically insulated. [4] The semiconductor material gas supply device according to any one of [1] to [3], wherein the remaining amount confirmation mechanism has two electrodes. [5] A semiconductor material gas supply device that uses liquid metal as a raw material for semiconductor material gas generation, A first reaction vessel containing the liquid metal in the lower part of its internal space and supplied with a raw material gas to the upper part of its internal space, The system includes a remaining amount confirmation mechanism for confirming the remaining amount of the liquid metal present in the internal space, The first reaction vessel has at least a bottom and side walls, and the material of the bottom and side walls is a conductor. The aforementioned remaining amount confirmation mechanism Two conductors connected to the aforementioned side wall, A semiconductor material gas supply device having a resistance measuring circuit connected to two of the aforementioned conductors. [6] A semiconductor material gas supply device that uses liquid metal as a raw material for semiconductor material gas generation, A first reaction vessel containing the liquid metal in the lower part of its internal space and supplied with a raw material gas to the upper part of its internal space, The system includes a remaining amount confirmation mechanism for confirming the remaining amount of the liquid metal present in the internal space, The aforementioned remaining amount confirmation mechanism A semiconductor material gas supply device having a gravimeter located below the first reaction vessel. [7] A semiconductor material gas supply device that uses liquid metal as a raw material for semiconductor material gas generation, A first reaction vessel containing the liquid metal in the lower part of its internal space and supplied with a raw material gas to the upper part of its internal space, The system includes a remaining amount confirmation mechanism for confirming the remaining amount of the liquid metal present in the internal space, The first reaction vessel has a lid, a bottom, and side walls, The aforementioned remaining amount confirmation mechanism An optical level sensor located above the first reaction vessel, A semiconductor material gas supply device having a window portion located in the lid portion and transmitting laser light. [8] Further comprising a second reaction vessel located below the first reaction vessel, The remaining amount confirmation mechanism, An optical level sensor located above the first reaction vessel, A window portion located in the lid portion and transmitting laser light, A tunnel portion that penetrates the bottom in the vertical direction and transmits the laser light, The semiconductor material gas supply device according to [7].

Advantages of the Invention

[0010] The semiconductor material gas supply device of the present invention can confirm the remaining amount of liquid metal without taking out the storage portion of liquid metal which is the raw material for semiconductor material gas generation.

Brief Description of the Drawings

[0011] [Figure 1] It is a cross-sectional view schematically showing an example of the configuration of a semiconductor material gas supply device which is an embodiment to which the present invention is applied. [Figure 2] It is a cross-sectional view schematically showing a first form of a remaining amount confirmation mechanism applicable to a semiconductor material gas supply device which is an embodiment of the present invention. [Figure 3] It is an enlarged cross-sectional view showing a part of the first form of the remaining amount confirmation mechanism applicable to a semiconductor material gas supply device which is an embodiment of the present invention. [Figure 4] It is a cross-sectional view showing a modification of the first form of the remaining amount confirmation mechanism applicable to a semiconductor material gas supply device which is an embodiment of the present invention. [Figure 5] It is a cross-sectional view schematically showing a second form of the remaining amount confirmation mechanism applicable to a semiconductor material gas supply device which is an embodiment of the present invention. [Figure 6] It is a cross-sectional view schematically showing a third form of the remaining amount confirmation mechanism applicable to a semiconductor material gas supply device which is an embodiment of the present invention. [Figure 7]This is a schematic cross-sectional view showing a fourth embodiment of a remaining amount confirmation mechanism applicable to a semiconductor material gas supply device, which is one embodiment of the present invention. [Modes for carrying out the invention]

[0012] Hereinafter, a semiconductor material gas supply device, which is one embodiment to which the present invention is applied, will be described in detail with reference to the drawings. Note that, for the sake of clarity, the drawings used in the following description may show enlarged versions of characteristic parts, and the dimensional ratios of each component may not be the same as in reality.

[0013] <Semiconductor material gas supply equipment> First, I will explain the configuration of a semiconductor material gas supply device, which is one embodiment of the present invention. As shown in Figure 1, the semiconductor material gas supply device 100 of this embodiment has a structure in which the first reaction vessel 1, the second reaction vessel 2, and the third reaction vessel 3 are stacked vertically in that order inside the storage container 13. The first reaction vessel 1, the second reaction vessel 2, and the third reaction vessel 3 each have internal spaces 1z, 2z, and 3z, respectively, defined by their lids, bottoms, and side walls. The lid of the second reaction vessel 2 may be substituted with the bottom of the first reaction vessel 1. Similarly, the lid of the third reaction vessel 3 may be substituted with the bottom of the second reaction vessel 2. In this way, the structure of the reaction vessels can be further simplified by substituting the bottom of one reaction vessel for the lid of the one below it. In this case, it is preferable that the bottom of the upper reaction vessel and the top of the lower reaction vessel are tightly sealed to prevent gas leakage from the internal space.

[0014] Each reaction vessel can withstand temperatures of 800°C or higher and can be made of, for example, quartz or graphite. However, graphite is preferred because, as will be described later, gas channels are arranged inside the side walls of the reaction vessels.

[0015] The storage container 13 is a cylindrical member with an internal space and open at both ends. The material of the storage container 13 is not particularly limited as long as it can withstand high temperatures of 800°C or higher; for example, it can be made of quartz.

[0016] A flange member 11 is located at the upper end of the storage container 13, closing the upper end opening of the storage container 13. Similarly, a flange member 12 is located at the lower end of the storage container 13, closing the lower end opening of the storage container 13. The flange member 12 is provided with inlets for the first raw material gas passage 6 and the second raw material gas passage 7, which will be described later, as well as an outlet for the material gas passage 8. The material of the flange members 11 and 12 is not particularly limited as long as it can withstand high temperatures of 800°C or higher; for example, it can be made of quartz.

[0017] A heating mechanism 18 for heating the reaction vessel inside the storage container is installed on the outside of the storage container 13. For example, a mantle heater can be used as the heating mechanism 18. The mantle heater is preferably capable of heating to 800°C or higher, and more preferably capable of heating to 1000°C or higher, in order to enhance the reactivity between the metal material and the raw material gas.

[0018] Gas passages are provided inside the side walls of each reaction vessel. The raw material gas G1, along with the carrier gas, is supplied to the upper part of the internal space 1z of the uppermost first reaction vessel 1 through the first raw material gas passage 6. The raw material gas G1, along with the carrier gas, is also supplied to the internal space 3z of the lowermost third reaction vessel 3 through the second raw material gas passage 7.

[0019] At least a portion of the raw material gas G1 supplied to the first reaction vessel 1 reacts with the metallic material M contained in the lower part of the internal space 1z to produce product gas G3. The product gas G3, along with the unreacted raw material gas G1 and carrier gas, is supplied to the upper part of the internal space 2z of the second reaction vessel 2 through the first product gas flow path 9.

[0020] At least a portion of the raw material gas G1 supplied to the second reaction vessel 2 reacts with the metal material M contained in the lower part of the internal space 2z to produce product gas G3. The product gas G3, along with the unreacted raw material gas G1 and carrier gas, is supplied to the upper part of the internal space 3z of the third reaction vessel 3 through the second product gas flow path 10.

[0021] The product gas G3 supplied to the third reaction vessel 3 reacts with the raw material gas G1 supplied to the internal space 3z through the second raw material gas channel 7 to produce semiconductor material gas G2. The produced semiconductor material gas G2 is discharged from the semiconductor material gas supply device 100 through the material gas channel 8.

[0022] The first raw material gas flow path 6 is formed by stacking the first reaction vessel 1, the second reaction vessel 2, and the third reaction vessel 3 vertically in that order, thereby connecting the raw material gas flow path inside the side wall of the first reaction vessel 1, the raw material gas flow path inside the side wall of the second reaction vessel 2, and the raw material gas flow path inside the side wall of the third reaction vessel 3.

[0023] The first product gas channel 9 and the second product gas channel 10 are formed by stacking the first reaction vessel 1 and the second reaction vessel 2, and the second reaction vessel 2 and the third reaction vessel 3 vertically in an upward and downward direction, respectively.

[0024] An insulating material 14 is placed on top of the first reaction vessel 1 via a spacer member 16. Furthermore, a heat insulating material 15 is placed at the bottom of the third reaction vessel 3 via a spacer member 17. Furthermore, the thermal insulation material 15 and the spacer member 17 are provided with a first raw material gas passage 6, a second raw material gas passage 7, and a material gas passage 8.

[0025] The insulating materials 14 and 15 reduce heat dissipation from each reaction vessel, preventing a decrease in the reactivity between the metal material M and the raw material gas G1. As an insulating material, materials that can withstand temperatures of 800°C or higher can be used, such as alumina fibers, foamed quartz, or vacuum insulating glass. However, alumina fibers are preferable because they are low-cost.

[0026] Metallic material M is contained in the lower parts of the internal spaces 1z and 2z of the first reaction vessel 1 and the second reaction vessel 2, respectively. The metallic material M is at least one selected from the group consisting of solid metals and liquid metals, and specifically, examples include gallium, aluminum, and indium. Gallium is preferred as the metallic material M.

[0027] Examples of raw material gas G1 include halogen gases and hydrogen halide gases. As the raw material gas G1, chlorine gas or hydrogen chloride gas is preferred, and chlorine gas is more preferred. Examples of carrier gases to be mixed with raw material gas G1 include nitrogen gas, hydrogen gas, argon gas, and helium gas. Preferably, the carrier gas is at least one selected from the group consisting of nitrogen gas, hydrogen gas, argon gas, and helium gas, with nitrogen gas or argon gas being more preferred, and nitrogen gas being even more preferred because it can be easily produced from air (atmosphere) and is inexpensive.

[0028] Next, the method of using the semiconductor material gas supply device 100 of this embodiment (method of supplying semiconductor material gas) will be described. The following explanation describes the case where gallium is used as the metal material M and chlorine gas is used as the raw material gas G1.

[0029] Gallium and chlorine gas react in the following two steps to produce gallium trichloride as a semiconductor material gas. 2Ga + Cl2(g) → 2GaCl(g) GaCl + Cl2(g) → GaCl3(g)

[0030] Specifically, first, an excess of chlorine gas is introduced into the uppermost first reaction vessel containing gallium. In the uppermost first reaction vessel 1, gallium monochloride (GaCl) is produced by the reaction of gallium with chlorine gas, and the GaCl and unreacted Cl2 flow into the lower second reaction vessel 2, which contains gallium. Since the second reaction vessel 2 contains gallium, the unreacted Cl2 flowing from the upper level reacts with the gallium to produce gallium monochloride (GaCl).

[0031] Finally, a large amount of gallium monochloride (GaCl) flows into the bottommost third reaction vessel 3. Then, by adding chlorine gas to the bottommost third reaction vessel 3, the second reaction between gallium monochloride and chlorine gas occurs, producing gallium trichloride (GaCl3).

[0032] In the semiconductor material gas supply device 100 of this embodiment, a two-stage reaction method is employed in which the first-stage reaction (GaCl production) occurs in a reaction vessel containing gallium, and the second-stage reaction (GaCl3 production) occurs in a reaction vessel not containing gallium.

[0033] Furthermore, in the semiconductor material gas supply device 100 of this embodiment, the footprint can be reduced by stacking multiple reaction vessels, and the surface area of ​​the metal raw material M can be easily increased, thus enabling the large-scale production of semiconductor material gas G2. The generated semiconductor material gas G2 is discharged from the semiconductor material gas supply device 100 and then transferred, for example, to the film deposition section of a semiconductor manufacturing apparatus, where it is used for wafer deposition.

[0034] As described above, in the semiconductor material gas supply device 100 of this embodiment, reaction vessels (generally also called "boats") stacked inside the device are arranged in a series of multiple stages vertically. Therefore, it is possible to increase the supply amount of semiconductor material gas and further reduce unreacted raw material gas.

[0035] Furthermore, according to the semiconductor material gas supply device 100 of this embodiment, raw material gas can be introduced into the reaction vessel using a gas channel provided inside the side wall, which is formed by stacking the reaction vessels vertically. Therefore, a gas channel can be formed by a simple method, and since there are no pipes requiring complex welding, a reaction vessel with low cost, good operability and maintainability can be realized.

[0036] The semiconductor material gas supply device 100 of this embodiment includes one of the following first to fourth embodiment remaining amount confirmation mechanisms in order to confirm the remaining amount of liquid metal M present in the internal space of the reaction vessel.

[0037] (1st form) As shown in Figure 2, the first embodiment of the remaining amount confirmation mechanism 200 applicable to the semiconductor material gas supply device 100 of this embodiment is located in the first reaction vessel 1 which contains liquid metal M in the lower part of the internal space 1z and has a pair of (two) electrodes 201, 202 located in the internal space 1z and a voltage detection circuit 203 which is electrically connected to the pair of electrodes 201, 202 via a conductor. In other words, the remaining amount confirmation mechanism 200 in this embodiment is an electrode-type level switch.

[0038] In this embodiment, the first reaction vessel 1 has a lid 1A, a bottom 1B, and side walls 1C, and these materials are conductive materials such as graphite. Furthermore, an insulating member 204 is provided on a portion of the upper part of the side wall 1C. The insulating member 204 adheres tightly to the wall surface of the side wall 1C due to the load of the lid portion 1A located on the upper part of the side wall 1C, thereby suppressing gas leakage from the semiconductor material to the minimum extent possible.

[0039] The pair of electrodes 201 and 202 are each bent into an L-shape and are positioned to penetrate the insulating member 204. As a result, the base ends of electrodes 201 and 202 are located outside the first reaction vessel 1, and the tips are located in the internal space 1z, which is partitioned by the lid 1A, the bottom 1B, and the side wall 1C.

[0040] The material of electrodes 201 and 202 is not particularly limited, but if the semiconductor material gas generated is a corrosive gas such as chloride, a corrosion-resistant material can be used. As a corrosion-resistant material, highly corrosion-resistant metals such as Inconel and Hastelloy are preferred, and carbon materials such as graphite are more preferred. By using a corrosion-resistant material for electrodes 201 and 202, the contamination of the semiconductor material gas with impurities can be reduced, and the lifespan of the electrodes can be extended.

[0041] The electrodes 201 and 202 are inserted through holes provided in the insulating member 204 so as not to interfere with the conductive material side wall 1C. This electrically insulates the electrodes 201 and 202 from the side wall 1C.

[0042] Here, the method of attaching electrodes 201 and 202 to the insulating member 204 is not particularly limited. For example, as shown in Figure 3, a flange portion 201A is provided on electrode 201, electrode 201 is inserted into the insulating member 204, and the flange portion 201A and the wall surface of the insulating member 204 are in close contact, and it can be fixed with screws 205 made of insulating material. The same applies to electrode 202. In this way, by creating a structure in which electrodes 201 and 202 and insulating member 204 are in close contact and fixed together, gas leakage from the gap between electrodes 201 and 202 and insulating member 204 can be suppressed.

[0043] As shown in Figure 2, the base ends of electrodes 201 and 202 are electrically connected to a voltage detection circuit 203 located in a sufficiently cooled position via wires or the like. On the other hand, the tips of electrodes 201 and 202 are positioned so as to float at different heights above the bottom of the internal space 1z. This ensures that the electrodes are insulated when the liquid level of the liquid metal M falls below the level of one of the tips of electrodes 201 or 202. In this way, the remaining amount confirmation mechanism 200 of this embodiment can confirm the remaining amount of liquid metal M by monitoring the conductivity between electrodes 201 and 202 using the voltage detection circuit 203. Therefore, it becomes possible to determine the appropriate timing for replenishing the liquid metal M to the first reaction vessel 1.

[0044] (A variation of the first form) As shown in Figure 4, the remaining amount confirmation mechanism 210, which is a modified example of the first embodiment applicable to the semiconductor material gas supply device 100 of this embodiment, is located in the first reaction vessel 1 which contains liquid metal M in the lower part of the internal space 1z, and has one electrode 201 located in the internal space 1z, conductors 206, 207, and an electrodetector circuit 203. In other words, the remaining charge confirmation mechanism 210, which is a modified version of this embodiment, differs in configuration from the remaining charge confirmation mechanism 200 in that it does not have an electrode 202. Therefore, components common to both the remaining charge confirmation mechanism 200 and 210 are given the same reference numerals and their descriptions are omitted.

[0045] The conductor 206 is located between the electrode 201 and the voltage detection circuit 203. In other words, the electrode 201 is electrically connected to the voltage detection circuit 203 via the conductor 206. Furthermore, the conductor 207 is located between the side wall 1C of the first reaction vessel 1 and the voltage detection circuit 203. That is, the side wall 1C, which is made of a conductive material, is electrically connected to the voltage detection circuit 203 via the conductor 207. As a result, when the liquid level of the liquid metal M falls below the tip of the electrode 201, the electrode 201 and the side wall 1C are insulated. Thus, the remaining amount confirmation mechanism 210, which is a modified version of this embodiment, can confirm the remaining amount of liquid metal M by monitoring the conductivity between the electrode 201 and the side wall 1C with the voltage detection circuit 203.

[0046] Furthermore, according to the remaining amount confirmation mechanism 210, which is a modified version of this embodiment, the first reaction vessel 1 (side wall 1C), which is made of a conductive material, is used as a substitute for one of the electrodes, thus reducing the number of electrodes inserted into the vessel by one. As a result, the structure of the remaining amount confirmation mechanism 210 is simplified, the number of parts is reduced, and gas leakage from the gap between the electrode 201 and the insulating member 204 can be further suppressed.

[0047] As described above, according to the first embodiment of the remaining amount confirmation mechanism 200,210, the remaining amount of liquid metal M can be confirmed by monitoring the conductivity between a pair of electrodes 201,202, or between electrode 201 and the side wall 1C, using an electrode-type level switch and a voltage detection circuit 203.

[0048] In the first embodiment of the remaining amount confirmation mechanism 200,210 described above, the case where the electrodes 201,202 are L-shaped was explained as an example, but the mechanism is not limited to this.

[0049] Furthermore, while the first embodiment of the remaining amount confirmation mechanism 200,210 described above was explained as having one or two electrodes as an example, it is not limited to this. For example, it may be configured to have three or more electrodes. In the case of a configuration with three or more electrodes, multiple patterns of liquid level height can be detected by arranging multiple electrodes at different lengths. Specifically, by making only one of the three electrodes shorter, it is possible to detect the upper and lower limits of the liquid level.

[0050] Furthermore, in the first embodiment of the remaining amount confirmation mechanism 200 described above, an example configuration was described in which an insulating member 204 is provided when the first reaction vessel 1 (side wall 1C) is made of a conductive material and is equipped with two electrodes, but the invention is not limited to this. For example, when the first reaction vessel 1 (side wall 1C) is made of a material other than a conductive material, the insulating member 204 may be omitted. Furthermore, if the first reaction vessel 1 (side wall 1C) is made of a conductive material, the insulating member 204 may be omitted. In this case as well, theoretically, the liquid level of the liquid metal M can be measured by measuring the resistance between electrodes 201 and 202.

[0051] Furthermore, in the first embodiment described above, a configuration in which the remaining amount confirmation mechanisms 200 and 210 are provided only in the first reaction vessel 1 was explained as an example, but the invention is not limited to this. For example, the remaining amount confirmation mechanisms 200 and 210 may be provided in the second reaction vessel 2 that contains the liquid metal M, or they may be provided in all reaction vessels that contain the liquid metal M. In other words, if the semiconductor material gas supply device 100 of the above-described embodiment is configured to include three or more reaction vessels, then the remaining amount checks 200 and 210 of this embodiment may be provided in one or more of the reaction vessels containing the liquid metal M.

[0052] (2nd form) As shown in Figure 5, the remaining amount confirmation mechanism 300, which is a second embodiment applicable to the semiconductor material gas supply device 100 of this embodiment, has two conductors 301 and 302 connected to the first reaction vessel 1 (side wall 1C) made of a conductive material, and a resistance measurement circuit 303 connected to the two conductors 301 and 302. In other words, the remaining amount confirmation mechanism 200 in this embodiment utilizes the change in the conductivity of the entire first reaction vessel 1.

[0053] Here, the resistance r of the object can be calculated using the following formula (1).

[0054]

number

[0055] In equation (1) above, "ρ" is the resistivity, "l" is the length of the object, and "s" is the cross-sectional area of ​​the object. In other words, the resistance of an object changes as its cross-sectional area changes.

[0056] Therefore, in this embodiment of the remaining amount confirmation mechanism 300, the first reaction vessel 1 is made of a conductive material, and conductive wires 301 and 302 are connected to two locations on the side wall 1C, preferably on opposite sides of the liquid metal M as shown in Figure 5, and the resistance value of the first reaction vessel 1 is measured by the resistance measurement circuit 303. As a result, when the amount of liquid metal M contained in the first reaction vessel 1 decreases, the cross-sectional area "s" of the liquid metal M with respect to the current direction decreases, and the resistance value of the entire vessel increases. Therefore, with the remaining amount confirmation mechanism 300 of this embodiment, the remaining amount of liquid metal M can be confirmed by monitoring the increase in this resistance value. Thus, it becomes possible to determine the appropriate timing for replenishing liquid metal M to the first reaction vessel 1.

[0057] As explained above, the remaining amount confirmation mechanism 300 of the second form allows the remaining amount of liquid metal M to be confirmed by monitoring the increase in the overall resistance of the first reaction vessel 1 containing the liquid metal M.

[0058] Furthermore, with the second form of the remaining amount confirmation mechanism 300, there is no need to place electrodes in the internal space 1z of the first reaction vessel 1, and therefore there is no need to provide through holes in the side wall 1C. This simplifies the structure of the remaining amount confirmation mechanism 300 and further suppresses gas leakage from the first reaction vessel 1.

[0059] Furthermore, in the second embodiment described above, a configuration in which the remaining amount confirmation mechanism 300 is provided only in the first reaction vessel 1 was explained as an example, but the invention is not limited to this. For example, the remaining amount confirmation mechanism 300 may be provided in the second reaction vessel 2 that contains the liquid metal M, or it may be provided in all reaction vessels that contain the liquid metal M. In other words, if the semiconductor material gas supply device 100 of the above-described embodiment is configured to include three or more reaction vessels, the remaining amount checker 300 of this embodiment may be provided in one or more of the reaction vessels containing the liquid metal M.

[0060] (3rd form) As shown in Figure 6, the third embodiment of the remaining amount confirmation mechanism 400 applicable to the semiconductor material gas supply device 100 of this embodiment has a plurality of weight sensors (weight measuring devices) 401, 401 located below the first reaction vessel 1. In other words, the remaining amount confirmation mechanism 400 in this embodiment uses a weight sensor 401.

[0061] The weight sensors (weight measuring devices) 401,401 are located below the first to third reaction vessels 1 to 3, directly below the spacer member 17, and are spaced apart in the circumferential direction. Thus, according to the remaining amount confirmation mechanism 400 of this embodiment, by placing the weight sensors 401, 401 directly below the spacer member 17 which is thermally shielded from the first to third reactors 1 to 3 by the heat insulating material 15, it can be suitably used even when the first to third reactors 1 to 3 containing the liquid metal M are heated to a temperature above the heat resistance temperature of the weight sensors 401, 401.

[0062] Furthermore, with the remaining amount confirmation mechanism 400 of this embodiment, since the weight sensors 401, 401 are placed in the space inside the storage container 13, the accuracy of detecting weight changes is improved without having to measure the weight of the entire semiconductor material gas supply device 100.

[0063] In the semiconductor material gas supply device 100 of this embodiment, as raw materials are consumed, the consumed amount is discharged as gas to the outside of the first to third reactors 1 to 3, thus reducing the weight of the first to third reactors 1 to 3. Therefore, with the remaining amount confirmation mechanism 400 of this embodiment, the remaining amount of liquid metal M can be confirmed by monitoring the weight changes of the first to third reactors 1 to 3 using multiple weight sensors 401, 401. Thus, it becomes possible to determine the appropriate timing for replenishing liquid metal M to the first reaction vessel 1.

[0064] In the third form of the remaining quantity confirmation mechanism 400 described above, the case in which multiple weight sensors 401, 401 are provided was explained as an example, but it is not limited to this. For example, a configuration with only one large weight sensor may also be used.

[0065] Furthermore, while the third embodiment of the remaining quantity confirmation mechanism 400 described above has been explained as an example in which multiple weight sensors 401, 401 are arranged in the space inside the storage container 13, the mechanism is not limited to this. One or more weight sensors may be arranged on the outside of the storage container 13 (for example, below the flange member 12).

[0066] (4th form) As shown in Figure 7, the fourth embodiment of the remaining amount confirmation mechanism 500 applicable to the semiconductor material gas supply device 100 of this embodiment includes an optical level sensor 501, window sections 502 and 503, and a tunnel section 504. In other words, the remaining amount confirmation mechanism 500 in this embodiment uses an optical level sensor 501.

[0067] The optical level sensor 501 irradiates light onto the object to be measured, detects the light reflected from the object, and measures the distance from the irradiated light and reflected light to the object. The optical level sensor 501 is not particularly limited, but an example is a laser level sensor. The optical level sensor 501 is located above the flange member 11.

[0068] The window portion 502 is located vertically below the optical level sensor 501 and is a member that closes the through hole that penetrates the flange member 11. Furthermore, the window portion 503 is located vertically below the optical level sensor 501 and the window portion 502, and is a member that closes the through hole that penetrates the lid portion 1A of the first reaction vessel 1. The windows 502 and 503 are preferably made of a material that transmits light from the optical level sensor 501 and is not corroded by semiconductor material gases. While not particularly limited, such materials include, for example, quartz.

[0069] The tunnel section 504 is located vertically below the optical level sensor 501 and the window sections 502 and 503, and is a through-hole that penetrates the bottom 1B of the first reaction vessel 1. Specifically, the tunnel section 504 has a columnar section erected vertically upward from the bottom 1B of the first reaction vessel 1 to a required height, and a through-hole that penetrates the central part of the columnar section vertically up and down. The tunnel section 504 connects the internal space 1z of the first reaction vessel 1 and the internal space 2z of the second reaction vessel 2. It is preferable that the tunnel section 504 be made of the same material as the bottom 1B of the first reaction vessel 1.

[0070] According to the remaining amount confirmation mechanism 500 of this embodiment, the liquid level of the liquid metal M contained in the second reaction vessel 2, the second stage from the top, can be confirmed by using the optical level sensor 501, the window sections 502 and 503, and the tunnel section 504. In this way, the remaining amount of liquid metal M can be confirmed by monitoring the liquid level of the liquid metal M contained in the second reaction vessel 2.

[0071] Furthermore, with the remaining amount confirmation mechanism 500 of this embodiment, since the tunnel section 504 has a columnar section erected vertically upward from the bottom 1B of the first reaction vessel 1 to a required height, the liquid level of the liquid metal M contained in the first reaction vessel 1 can be regulated. As a result, when supplying the liquid metal M to the first reaction vessel 1, the liquid level of the liquid metal M remains constant.

[0072] Furthermore, according to the remaining amount confirmation mechanism 500 of this embodiment, the tunnel section 504 has a through hole that penetrates the central part of the columnar section vertically up and down, and can therefore be used as both a gas flow path and an inlet from the first stage to the second stage of the liquid metal M.

[0073] In the fourth embodiment of the remaining amount confirmation mechanism 500 described above, a configuration comprising a tunnel section 504 and monitoring the liquid level of the liquid metal M contained in the second reaction vessel 2 was described as an example, but the mechanism is not limited to this. For example, the tunnel section 504 may be omitted, and a configuration that monitors the liquid level of the liquid metal M contained in the first reaction vessel 1 may be used.

[0074] The technical scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention. [Explanation of symbols]

[0075] 1. First reaction vessel 1A Lid 1B Bottom 1C side wall 1z internal space 2. Second reaction vessel 2z interior space 100 Semiconductor material gas supply equipment 200, 210, 300, 400, 500 Battery level indicator 201,202 electrode 203 Voltage detection circuit 206,207 Conductor 301,302 Conductor 303 Resistance Measurement Circuit 401 Weight Sensor 501 Optical Level Sensor 502, 503 Window section 504 Tunnel section M liquid metal

Claims

[Claim 1] A semiconductor material gas supply device that uses liquid metal as a raw material for semiconductor material gas generation, A first reaction vessel containing the liquid metal in the lower part of its internal space and supplied with a raw material gas to the upper part of its internal space, A second reaction vessel is located below the first reaction vessel, containing the liquid metal in the lower part of its internal space, and supplied with a gas containing the product gas generated in the first reaction vessel to the upper part of its internal space. The second reaction vessel comprises a remaining amount confirmation mechanism for confirming the remaining amount of the liquid metal present in the internal space of the second reaction vessel, The first reaction vessel has a lid, a bottom, and side walls, The aforementioned remaining amount confirmation mechanism An optical level sensor located above the first reaction vessel, A window portion located in the aforementioned lid portion, which transmits laser light, A semiconductor material gas supply device having a tunnel portion that penetrates the bottom portion vertically in the vertical direction and transmits the laser light.

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