Gasifier

Abstract

The utility model provides a gasifier which can efficiently and stably gasify liquid raw materials for semiconductor manufacturing at the temperature as low as possible without uneven heating. A vaporizer (10) is configured from a liquid raw material supply unit (12) for supplying a liquid raw material (LM) for semiconductor manufacturing, a vaporizing unit (20) having a vaporizing space (K) for vaporizing the supplied liquid raw material (LM) therein, and a raw material gas discharge unit (40) for discharging the vaporized raw material gas (VG) to the next step. The gasification unit (20) includes: a gasifier main body (22) which is configured from a transparent member through which infrared rays are transmitted and through which the infrared rays pass through the gasification space (K) and through which the infrared rays are transmitted from one side wall (22h) to the other side wall (22h) facing the gasification space (K); a transparent spherical body (30) which is filled in the gasification space (K) and through which infrared rays are transmitted; a heater (H) that is disposed so as to provide a gap (d) having a width (M) with respect to the gasifier main body (22), and that irradiates the gasifier main body (22) with infrared rays; and a reflection member (28) having a heater (H) interposed therebetween, the surface facing the gasifier body (22) being a mirror surface (28k) for reflecting infrared rays.

Description

Technical Field

[0001] This invention relates to a vaporizer that enables liquid raw materials used in semiconductor manufacturing processes to be vaporized efficiently and stably without uneven heating. Background Technology

[0002] In semiconductor manufacturing processes, there are processes such as oxide film formation or thin film formation that require liquid raw materials to perform.

[0003] For example, in the oxide film formation process, in order to form an oxide film on the surface of a silicon wafer, a raw material gas (specifically, an oxidizing gas such as water vapor or hydrogen peroxide vapor) for oxide film formation is supplied into a high-temperature oxidation furnace to perform the oxide film formation process.

[0004] In the thin film formation process, in order to form a thin film on a substrate, liquid raw materials are vaporized into raw material gases, which are then supplied to the thin film forming apparatus to perform the thin film formation process.

[0005] Furthermore, a vaporizer is used as equipment for supplying the liquid compound by vaporizing it in the aforementioned processes. A conventional vaporizer includes, for example, a vaporizer with a plurality of holes within its main body. This vaporizer surface is heated by a heater, and simultaneously, liquid raw material is ejected from a nozzle and atomized into fine droplets, which are then sprayed onto the vaporizer surface along with a carrier gas flow, thereby vaporizing it. In such a vaporizer, since the fine droplets come into contact with the ventilating components, the vaporization efficiency can be improved (see Patent Documents 1 and 2).

[0006] However, conventionally, the ventilator used to vaporize the fine droplets of liquid feedstock is heated by heat conduction from a heater. This results in sections far from the heater where heat cannot reach them sufficiently, leading to lower temperatures and an inability to uniformly supply heat to the ventilator. Consequently, droplets may not be vaporized in these lower-temperature sections, causing blockages. If the vaporization of the liquid feedstock is not 100%, the unvaporized liquid can form particles that adhere to the wafer surface, severely damaging thin film formation. Therefore, a vaporizer as described in Patent Document 3 has been proposed.

[0007] In the vaporizer described in Patent Document 3, the following improvement was made: an opaque material, such as ceramic, that easily absorbs infrared radiation is used to form a ventilating component that vaporizes droplets of liquid raw material, so that the temperature of the ventilating component becomes uniform throughout when the droplets of liquid raw material are vaporized through this opaque ventilating component. That is, infrared radiation from the heater is irradiated onto the entire outer surface of the ventilating component disposed in the vaporization section through a transparent quartz sleeve.

[0008] Existing technical documents

[0009] Patent documents

[0010] Patent Document 1: Japanese Patent Application Publication No. 2005-347598

[0011] Patent Document 2: Japanese Patent Application Publication No. 10-85581

[0012] Patent Document 3: Japanese Patent Application Publication No. 2009-188266 Utility Model Content

[0013] The problem to be solved by utility models

[0014] In this way, the radiant heat from the heater can be used to uniformly heat the entire outer surface of the ventilated component, and all droplets flowing over the outer surface of the ventilated component can be vaporized without any omissions.

[0015] On the other hand, infrared rays cannot penetrate opaque ventilated components, and the inside of the ventilated components heats up through heat transfer from the surface.

[0016] On the other hand, droplets flowing over the surface of the ventilating component, along with the airflow, flow from the surface of the ventilating component through the internal micropores to the inner surface side as the vaporized gas is discharged.

[0017] If the thickness of the ventilated component is large, the temperature on its inner surface will be lower than that on its outer surface, which is directly exposed to infrared radiation. This temperature unevenness can easily lead to blockage on the inner surface of the ventilated component. Consequently, the thickness of the ventilated component is limited, thus hindering vaporization efficiency.

[0018] In addition to temperature unevenness, a key aspect of liquid feedstock vaporization processes is preventing excessive temperature increases during vaporization. This is because liquid compounds used in semiconductor film deposition, for example, are temperature-sensitive and readily polymerize at high temperatures. As the temperature rises, dimers form, then trimers, and finally polymers, increasing their molecular weight—in other words, becoming high-molecular-weight compounds. This results in higher boiling points, making vaporization difficult and ultimately leading to solidification. Consequently, film formation becomes impossible. Further temperature increases cause decomposition, further hindering film formation. Therefore, vaporizers must operate at the lowest possible temperature. Thus, vaporizers aim to achieve vaporization at the lowest possible temperature with an extremely uniform temperature distribution.

[0019] This invention was made in view of the above-mentioned problems, and provides a vaporizer that can vaporize liquid raw materials for semiconductor manufacturing efficiently and stably at the lowest possible temperature without uneven heating.

[0020] Technical means for solving problems

[0021] To achieve the above objectives, the present invention (technical solution 1) comprises the vaporizer 10 as follows.

[0022] A vaporizer 10 comprises a liquid raw material supply unit 12 for supplying liquid raw material LM for semiconductor manufacturing, a vaporization unit 20 having a vaporization space K inside for vaporizing the supplied liquid raw material LM, and a raw material gas discharge unit 40 for sending the vaporized raw material gas VG to the next process.

[0023] The vaporizer 10 is characterized in that it includes:

[0024] The vaporizer body 22, which allows infrared light to pass through the vaporization space K and be transmitted from one side wall 22h to the opposite side wall 22h, is made of a transparent component.

[0025] A transparent spherical body 30 is filled in the vaporization space K and allows infrared light to pass through.

[0026] A heater H, configured with a gap d of width M relative to the vaporizer body 22, irradiates the vaporizer body 22 with infrared radiation; and

[0027] The reflective component 28 has a mirror 28k on the side that places the heater H in the middle and faces the vaporizer body 22 to reflect infrared light.

[0028] Technical solution 2 is a technical solution in which an auxiliary reflective component 29 is also provided on the heater H. Figure 2 , Figure 3 Based on the vaporizer 10 described in technical solution 1, the vaporizer 10 is characterized in that,

[0029] On the side of the heater H opposite to the vaporizer body 22, there is an auxiliary reflective component 29 with a mirror 29k that reflects infrared light on the side opposite to the vaporizer body 22.

[0030] Technical solution 3 is a modified example of the vaporizer body 22. Figure 7 Based on the vaporizer 10 described in technical solution 1, the vaporizer 10 is characterized in that,

[0031] The vaporizer body 22 is made of tubing formed in a spiral shape.

[0032] Technical solution 4 involves ventilation of gap d. Figure 2 The technical solution described in technical solution 1, based on the vaporizer 10, is characterized in that:

[0033] The vaporization section 20 is provided with a displacement gas supply section 25 that communicates with the gap d and supplies displacement gas, and a displacement gas discharge section 26 that discharges the supplied displacement gas. The gap d between the vaporizer body 22 and the heater H becomes the passage for the displacement gas.

[0034] Technical solution 5 is a technical solution involving the size of the gap d. Figure 4 Based on the vaporizer 10 described in technical solution 1, the vaporizer 10 is characterized in that,

[0035] The width M of the gap d is formed to be greater than the thickness δ of the temperature boundary layer T formed around the heater H.

[0036] Utility Model Effect

[0037] According to this utility model (technical solution 1), since the vaporizer body 22 and the spherical body 30 are made of transparent components that allow infrared rays to pass through, the infrared rays emitted from the heater H can pass through them uniformly and without unevenness. Furthermore, due to repeated reflections by the reflective component 28, the infrared rays pass through the vaporizer body 22 and the spherical body 30 uniformly, heating all the liquid raw material LM flowing down between the spherical bodies 30 uniformly and without unevenness, thereby vaporizing it.

[0038] Furthermore, the heater H is positioned relative to the vaporizer body 22 with a gap d of width M, thus blocking heat conduction from the heater H to the vaporizer body 22, which causes uneven heating. As a result, the liquid feedstock LM supplied to the vaporization space K is uniformly and directly heated only by radiative heat based on infrared radiation during its flow down between the spheres 30 filling the vaporization space K.

[0039] If the vaporizer body 22 is formed in a spiral shape (technical solution 3), the flow path of the liquid raw material LM becomes longer, and the liquid raw material LM flows down while swirling, so the exposure time to infrared radiation is longer, which can achieve more reliable vaporization.

[0040] Furthermore, the gap d between the vaporizer body 22 and the heater H becomes a passageway. If the displacement gas flows into this gap d (technical solution 4), the heated gas (air) that has accumulated in this part and been heated by the heater H is discharged. As a result, the liquid feedstock LM supplied to the vaporization space K is not affected by the heated gas (air) and is heated more uniformly and directly only by the radiative heat based on the infrared rays emitted from the heater H.

[0041] In addition, if the size (width M) of the gap d is made to be greater than the thickness δ of the temperature boundary layer T (technical solution 5), the heat transfer from the displacement gas flowing through the gap d, which serves as the passage, to the vaporizer body 22 is reliably blocked. Attached Figure Description

[0042] Figure 1 This is a cross-sectional view of the vaporizer according to the first embodiment of this utility model.

[0043] Figure 2 yes Figure 3 A-A' section view.

[0044] Figure 3 yes Figure 1 The B-B' cross-section view in the image.

[0045] Figure 4 yes Figure 2 A magnified view of the gap in the image.

[0046] Figure 5 This is a cross-sectional view of the vaporizer according to the second embodiment.

[0047] Figure 6 yes Figure 5 The C-C' cross-section view.

[0048] Figure 7 (a) is a cross-sectional view of the vaporizer of the third embodiment, and (b) is another example of the straight pipe section.

[0049] Figure 8 This is a schematic diagram showing the state in which the liquid material flowing between the spheres is heated by radiative heat. Detailed Implementation

[0050] The present invention will now be described with reference to the accompanying drawings. The vaporizer 10 vaporizes the liquid raw material LM into a raw material gas VG, which is supplied to various semiconductor manufacturing apparatuses using the raw material gas VG. It is generally composed of a liquid raw material supply unit 12, a vaporization unit 20, and a raw material gas discharge unit 40.

[0051] The liquid raw material supply unit 12 supplies liquid raw material LM to the vaporization unit 20, which vaporizes the supplied liquid raw material LM. The raw material gas discharge unit 40 discharges the vaporized raw material gas VG to the next process. The liquid raw material supply unit 12 can supply liquid raw material LM in the form of droplets or in the form of atomized liquid raw material LM, and is appropriately selected to match the specifications required for the vaporizer 10.

[0052] There are various types of liquid raw materials (LM), which are appropriately selected based on the raw material gas (VG) used in various semiconductor manufacturing equipment. Here, hydrogen peroxide water is cited as a representative example.

[0053] (First implementation method:) Figures 1-3 )

[0054] As described above, the liquid feedstock supply section 12 of the vaporizer 10 of this utility model can supply liquid feedstock LM in the form of droplets or in the form of atomized liquid feedstock LM. Hereinafter, the case of atomized liquid feedstock LM will be described as an example, and the case of supplying liquid feedstock LM in the form of droplets will be described in detail later.

[0055] The liquid feedstock supply unit 12 includes a liquid feedstock inlet pipe 12a and a carrier gas inlet pipe 12b. The liquid feedstock inlet pipe 12a protrudes from the center of the upper surface of the liquid feedstock supply unit 12, and a liquid feedstock supply hole 12c is provided through its center for the liquid feedstock LM to pass through. The front end of the liquid feedstock supply hole 12c is narrowed into a conical shape, and a spray nozzle 12d is provided that opens on the bottom surface of the liquid feedstock supply unit 12.

[0056] A carrier gas inlet pipe 12b is provided on the side of the liquid raw material inlet pipe 12a, and a carrier gas supply path 12e connected to the spray nozzle 12d and exerting the Venturi effect is provided on the outer periphery of the liquid raw material inlet pipe 12a.

[0057] The vaporization section 20 is generally composed of a vaporizer body 22, a spherical body 30, a heater H, and a reflector component 28.

[0058] The vaporizer body 22 is its upper surface ( Figure 1 The hollow container is a cylindrical structure with an opening on the upper side and a closed bottom side. The closed bottom side is designated as the bottom component 22s. The opening end on the upper surface is sealed by the main body of the liquid feedstock supply section 12. The main body that seals the opening end on the upper surface of the vaporizer body 22 is designated as the top component 22t. The space between the top component 22t and the bottom component 22s of the vaporizer body 22 is the vaporization space K for vaporizing the liquid feedstock LM. The cylindrical portion of the hollow container is the sidewall 22h.

[0059] As for the materials of the vaporizer body 22 and the liquid raw material supply section 12, transparent components that allow infrared rays emitted from the heater H to pass through are selected. In this embodiment, transparent quartz glass is used.

[0060] The interior of the vaporizer body 22 (vaporization space K) is filled with spherical bodies 30. Figure 1 In order to atomize the liquid raw material LM, the spherical body 30 is filled with an open space in the upper part of the spherical body 30 in such a way as to form an atomization space S in the upper part of the spherical body 30.

[0061] Similar to the vaporizer body 22, the sphere 30 is also selected as a transparent component that allows infrared light emitted from the heater H to pass through. In this embodiment, a sphere made of transparent quartz glass and having a diameter of, for example, 2 mm to 5 mm is used.

[0062] A porous filter 23 is provided on the filled spherical body 30 as needed. As for the porous filter 23, the material of the porous filter 23 is not limited as long as it is not affected by the liquid raw material LM and can allow the liquid raw material LM to pass through smoothly. Here, a porous semi-molten quartz glass porous body is used, which is formed by melting and bonding the contact parts of quartz glass powder particles in a semi-molten state, so that infrared rays emitted from the heater H can be transmitted and can be welded and fixed to the vaporizer body 22.

[0063] The reason for using transparent quartz glass as the material for the vaporizer body 22 and the spherical body 30 is that infrared rays emitted from the heater H can be transmitted, and the infrared rays can be transmitted to the center of the vaporizer body 22.

[0064] In this embodiment, the spherical body 30 is spherical, but not limited to spheres; for example, it could also be granular quartz. Since the surface area is larger in this case, it is preferable in terms of improving the gasification efficiency of the liquid feedstock. However, a shape that would break due to vibration or other external forces, resulting in particles, is not used.

[0065] A tubular feed gas discharge section 40 is provided through a hole in the lower side of the hollow container constituting the vaporizer body 22. A porous mass filter 24 is installed at the end of the feed gas discharge section 40 on the vaporizer body side. The porous mass filter 24 only needs to be able to allow the feed gas VG to pass through smoothly without being affected by it. The porous mass filter 24 is the same filter as the porous mass filter 23 described above.

[0066] Furthermore, a cylindrical heating block 60 with a built-in raw material gas heater GH is installed on the outer periphery of the tubular raw material gas discharge section 40.

[0067] On both sides of the vaporizer body 22, multiple heaters (two in this embodiment) are erected.

[0068] A gap d is provided between each heater H and the side wall 22h of the vaporizer body 22. This blocks heat transfer from the heater H to the vaporizer body 22. However, since gas (air) exists within this gap d, heat from the heater H will still transfer to the vaporizer body 22. Therefore, as will be described later, the gap d is considered as a passage for gas replacement.

[0069] The reflective component 28 is a cylindrical component designed to reflect infrared rays emitted from the heater H toward the vaporization space K. Its inner surface is precision-machined into a mirror surface 28k by electroplating or grinding, or by attaching aluminum foil to achieve the same surface. The reflective component 28 is as follows... Figure 3 It is thus arranged outside the heater H in a manner that surrounds the vaporizer body 22. A top plate 21 is installed at the upper end of the reflector 28, and a bottom plate 27 is installed at the lower end of the reflector 28.

[0070] Through these reflective components 28, the sidewalls 22h of the vaporizer body 22, the top plate 21 and the bottom plate 27, a hollow annular space is formed inside, which houses the heater H.

[0071] exist Figure 3 An auxiliary reflective element 29 is used in the heater H. Since the main reflective element 28 surrounds the vaporizer body 22, this auxiliary reflective element 29 is not necessary. The auxiliary reflective element 29 is located on the back side of the heater H, that is, on the side opposite to the side wall 22h of the vaporizer body 22, and is integrally located on the back side of the heater H. The surface opposite to the vaporizer body 22 becomes a mirror surface 29k.

[0072] Next, the method for vaporizing the liquid feedstock LM using the vaporizer 10 will be described. The heater H is energized, creating a vaporization space K where the liquid feedstock LM can be vaporized. Once vaporization is achieved, the liquid feedstock LM is supplied to the liquid feedstock inlet pipe 12a of the liquid feedstock supply unit 12, and the carrier gas CG is supplied to the carrier gas inlet pipe 12b. This generates a Venturi effect, causing the liquid feedstock LM to atomize from the spray nozzle 12d and be evenly distributed within the atomization space S.

[0073] The mist-like liquid raw material LM, dispersed in the atomizing space S, is evenly poured onto the porous filter 23 and flows down to the side of the spherical body 30.

[0074] Regarding the spherical bodies 30 within the vaporizer body 22, adjacent spherical bodies 30 are in point contact with each other and support each other, forming a gap P (approximately triangular in plan view) between them, which is composed of complex concave spherical surfaces. Figure 8 The liquid raw material LM flowing down towards the spherical body 30 wets the surface of the spherical body 30 while flowing down, or a considerable portion of the liquid raw material LM accumulates in the void P and flows down while forming a pooled liquid.

[0075] On the other hand, infrared rays emitted from the heat source of heater H are emitted radially. On the side of heater H facing the vaporizer body 22, a considerable portion of the infrared rays travel toward the vaporizer body 22. Infrared rays exiting to the back side are reflected by the auxiliary reflector 29 on the back of heater H (or by the cylindrical main reflector 28 if the auxiliary reflector 29 is absent) and travel toward the vaporizer body 22.

[0076] The vaporizer body 22 is formed of transparent quartz glass that transmits infrared light. Therefore, infrared light traveling towards the vaporizer body 22 is refracted and transmitted through the sidewall 22h of the vaporizer body 22. Since the interior of the vaporizer body 22 is filled with spherical bodies 30, infrared light reaching the vaporization space K inside the vaporizer body 22 is refracted and transmitted through these spherical bodies 30 to the opposite sidewall 22h, and then refracted and transmitted through that sidewall 22h. To avoid complicating the accompanying drawings, infrared light is shown as a straight line.

[0077] Most of the infrared radiation transmitted through the vaporizer body 22 is reflected by the mirror 28k on the opposite side of the cylindrical reflector 28 and then transmitted back through the vaporizer body 22. The remaining infrared radiation is reflected by the auxiliary reflector 29. This process is repeated instantaneously and infinitely within the cylindrical reflector 28.

[0078] On the other hand, the infrared radiation within the vaporization space K of the vaporizer body 22 becomes instantaneously uniform due to the infinite, instantaneous reflection. Consequently, the temperature of the liquid feedstock LM, which absorbs uniform infrared radiation as it flows through the vaporization space K, becomes uniform throughout the entire vaporization space K. In other words, there is almost no heating through heat transfer from the vaporizer body 22 and the spherical body 30; the liquid feedstock LM is heated solely by uniform infrared radiation.

[0079] Here, when the infrared radiation used is mid-infrared with a wavelength of 2.5 μm to 4 μm, the absorption peak wavelength (3 μm) of water, which is the liquid feedstock LM, is included. Therefore, a portion of the mid-infrared radiation reaching the vaporizer body 22 is absorbed by the thin film of the liquid feedstock LM formed on the surface of the sphere 30, or by the liquid feedstock LM accumulated in the voids P, causing them to vaporize. If the film thickness of the liquid feedstock LM is too small, the infrared radiation is transmitted as is. Since the sphere 30 is formed of transparent quartz glass that allows infrared radiation to pass through, the infrared radiation that is not absorbed by the liquid feedstock LM passes through the sphere 30 and comes out to the opposite side.

[0080] Infrared rays not absorbed by the liquid feedstock LM are successively transmitted through the spherical body 30 filled in the vaporizer body 22, and emitted outward through the side wall 22h on the opposite side of the vaporizer body 22. The infrared rays emitted from the vaporizer body 22 are reflected by the mirror 28k on the opposite side of the reflecting component 28 (or part of it is reflected by the auxiliary reflecting component 29) and return to the vaporizer body 22.

[0081] The volume of the raw material gas VG after gasification in the gasification space K increases sharply, and it is discharged from the raw material gas discharge section 40 toward the next process.

[0082] In the vaporizer 10 of this invention, since the liquid raw material LM inside the vaporization space K can be heated uniformly and unevenly using only infrared light, the vaporizer body 22 can be enlarged. Furthermore, even with the enlarged vaporizer body 22, there will be no outflow of unvaporized liquid raw material LM particles that could potentially reduce the quality of the film formed on the wafer. Moreover, since uniform heating is achieved using only infrared light as described above, the liquid raw material LM can be vaporized at the necessary minimum temperature during heating, preventing excessive temperature increases. In other words, using the vaporizer 10 of this invention provides stable and significantly improved vaporization efficiency.

[0083] The above describes the situation where the liquid feedstock LM is supplied in a mist form. If the liquid feedstock LM is supplied without using a carrier gas CG, the liquid feedstock LM will drip and spread throughout the central portion of the porous filter 23. Then, it will flow down as usual, gradually diffusing as it flows down through the layer of spheres 30. Even in this case, since the infrared state of the vaporization space K is uniform, uniform vaporization is ensured, as described above.

[0084] exist Figures 1-3 The example shown takes into account the thermal movement to the vaporizer body 22 within the space where the heater H is located.

[0085] As described above, when the heater H is heated, the temperature of the surrounding gas (air) rises. This heated gas (air) heats the sidewall 22h of the vaporizer body 22. Therefore, the width M of the gap d can be improved, or the gap d can be used as a passage for the displacement gas. This applies to all embodiments.

[0086] Therefore, as shown in the attached diagram, a hole is provided in the bottom plate 27 as a displacement gas supply section 25, and a hole is provided in the top plate 21 as a displacement gas discharge section 26. This allows the displacement gas (air) to flow into the space where the heater H is located. Consequently, the surrounding gas (air) heated by the heater H rises and is discharged from the displacement gas discharge section 26, while ambient air at room temperature flows in from the displacement gas supply section 25, maintaining the space where the heater H is located at the temperature of the displacement gas (air). As a result, most of the thermal influence of the heater H on the vaporizer body 22 within the space where the heater H is located is eliminated.

[0087] However, the spacing M of the aforementioned gap d becomes a problem. Room temperature outside gas flowing in from the displacement gas supply section 25 rises along the heater H and gradually heats up. When the distance (width M) between the heater H and the side wall 22h of the vaporizer body 22 is close to and less than the thickness δ of the temperature boundary layer T, the displacement gas flowing along the heater H and heated by the heater H will come into contact with the side wall 22h of the vaporizer body 22. Therefore, the temperature of the side wall 22h will be affected by the heater H.

[0088] Therefore, in such Figure 4 As shown, when the width M between the heater H and the sidewall 22h of the vaporizer body 22 is greater than the thickness δ of the temperature boundary layer T, unheated displacement gas flows along the sidewall 22h between the heated temperature boundary layer T and the sidewall 22h, blocking the thermal influence of the heated temperature boundary layer T. Therefore, the influence of the heated temperature boundary layer T within the space where the heater H is located is reliably eliminated.

[0089] (Second implementation method:) Figure 5 , Figure 6 )

[0090] This situation occurs when the vaporizer body 22 is a double tube and a heater H is installed inside the inner tube 22b.

[0091] The vaporizer body 22 consists of a cylindrical outer tube 22a, an inner tube 22b with its upper portion shaped like a hemisphere, and a bottom component 22s that seals the bottom of both. The upper opening of the outer tube 22a is closed by a block portion (top component 22t) of the liquid feed supply section 12. The upper end of the inner tube 22b is positioned directly below the liquid feed inlet pipe 12a. The space between the outer tube 22a and the inner tube 22b is a vaporization space K, filled with spherical bodies 30. The spherical bodies 30 are filled to the height covering the upper end of the inner tube 22b. A porous filter 23 is provided on the spherical bodies 30 as needed. In the embodiment shown in the figures, the porous filter 23 is not depicted. The space between the spherical bodies 30 (porous filter 23) and the lower surface of the top component 22t is an atomization space S.

[0092] A gap d is provided between the mirror surface 28k of the reflective component 28 and the outer tube 22a to prevent heat interference from the reflective component 28. A gap d is also provided between the heater H and the inner tube 22b to prevent heat interference from the reflective component 28. A displacement gas supply section 25 and a displacement gas discharge section 26 connected to these gaps d are provided to allow displacement gas to flow through. Furthermore, as described above, the gap d can be made larger than the thickness δ of the temperature boundary layer T to prevent heat interference from the heater H. All other configurations are the same as in the first embodiment.

[0093] In addition, a heating block 60 is provided on the bottom plate 27 covering the bottom of the reflective component 28, and a raw material gas heater GH is installed thereon.

[0094] In the vaporizer 2 of the second embodiment, the liquid feedstock LM is atomized in the same manner as in the first embodiment. Although not shown, the case where the liquid is supplied as droplets without using a carrier gas CG differs from the first embodiment.

[0095] That is, the dripping liquid raw material LM falls onto the spherical body 30 directly above the hemispherical head of the inner tube 22b and spreads throughout this part, passing through the porous filter 23, or flowing into the gaps P between the spherical bodies 30 as before. Because there is a hemispherical head directly below this part, the flowing liquid raw material LM diffuses along the hemispherical head, spreading around the inner tube 22b as before while flowing down. During this process, it is uniformly heated and vaporized by radiant heat, and discharged from the raw material gas discharge section 40.

[0096] (Third implementation method:) Figure 7 )

[0097] This is an example of using a spiral-shaped transparent quartz glass tube to form the vaporizer body 22. Porous filters 23 and 24 are respectively installed on the upper or lower straight tube sections 22c and 22d, and spherical bodies 30 are filled therebetween.

[0098] The reflective component 28 is cylindrical, with a top plate 21 and a bottom plate 27 at its upper and lower ends, respectively. A transparent quartz glass tube, which serves as the outer shell of the heater H, is inserted through the center of the top plate 21 and the bottom plate 27, and the heat source of the heater H is arranged inside the tube along the vertical direction.

[0099] A gap d is provided between the transparent quartz glass tube of heater H and the spiral vaporizer body 22. Although not shown, the displacement gas can be directed to this part, and the width M of the gap d can be greater than or equal to the thickness δ of the temperature boundary layer T.

[0100] In such a vaporizer 10, the liquid raw material LM supplied from the liquid raw material supply section 12 flows into the filling section of the spherical body 30 through the upper porous filter 23 and is vaporized while rotating in a spiral.

[0101] By forming a spiral in the vaporizer body 22, the vaporization path of the liquid feedstock LM can be lengthened while the height direction of the vaporizer 10 can be compressed, making the vaporizer 10 compact.

[0102] In addition, it can also be like Figure 7 (b) In that case, the straight tube portion 22c·22d is narrowed so that its inner diameter is less than the outer diameter of the spherical body 30, and this portion replaces the porous filter 23·24 on the upper or lower side.

[0103] Explanation of reference numerals in the attached figures

[0104] CG: Carrier gas, d: Gap, H: Heater, GH: Feed gas heater, K: Vaporization space, LM: Liquid feed gas, M: Gap width, P: Void, S: Atomization space, T: Temperature boundary layer, VG: Feed gas, δ: Temperature boundary layer thickness

[0105] 10: Vaporizer; 12: Liquid feedstock supply section; 12a: Liquid feedstock inlet pipe; 12b: Carrier gas inlet pipe; 12c: Liquid feedstock supply hole; 12e: Carrier gas supply path; 12d: Spray nozzle; 20: Vaporization section; 21: Top plate; 22: Vaporizer body; 22a: Outer pipe; 22b: Inner pipe; 22c: Upper straight pipe section; 22d: Lower straight pipe section; 22h: Side wall; 22s: Bottom component; 22t: Top component; 23-24: Porous filter; 25: Displacement gas supply section; 26: Displacement gas discharge section; 27: Bottom plate; 28: Reflecting component; 28k: Mirror; 29: Auxiliary reflecting component; 29k: Mirror; 30: Spherical body; 40: Feedstock gas discharge section; 60: Heating block.

Claims

1. A vaporizer (10) which is composed of a liquid material supply section (12) which supplies a liquid material (LM) for use in semiconductor manufacturing, a vaporization section (20) which has a vaporization space (K) inside which the supplied liquid material (LM) is vaporized, and a material gas discharge section (40) which discharges a vaporized material gas (VG) to a next process, characterized in that the vaporization section (20) comprises: a vaporizer main body (22) which transmits infrared rays from one side wall (22h) to the opposite side wall (22h) of the vaporization space (K) and is composed of a transparent member; a transparent spherical body (30) which is filled in the vaporization space (K) and transmits infrared rays; a heater (H) which is disposed so as to have a gap (d) of a width (M) with respect to the vaporizer main body (22) and which irradiates infrared rays to the vaporizer main body (22); and a reflection member (28) which has a mirror surface (28k) which reflects infrared rays on a surface opposite to the vaporizer main body (22) with the heater (H) interposed therebetween. An auxiliary reflection member (29) which has a mirror surface (29k) which reflects infrared rays on a surface opposite to the vaporizer main body (22) is provided on a surface of the heater (H) opposite to the vaporizer main body (22). The vaporizer main body (22) is composed of a pipe material which is formed in a spiral shape. A displacement gas supply section (25) which communicates with the gap (d) and supplies a displacement gas, and a displacement gas discharge section (26) which discharges the supplied displacement gas are provided in the vaporization section (20), and the gap (d) between the vaporizer main body (22) and the heater (H) becomes a passage of the displacement gas. The width (M) of the gap (d) is formed to be larger than the thickness (δ) of a temperature boundary layer (T) formed around the heater (H).

1. A vaporizer (10) which is composed of a liquid material supply section (12) which supplies a liquid material (LM) for use in semiconductor manufacturing, a vaporization section (20) which has a vaporization space (K) inside which the supplied liquid material (LM) is vaporized, and a material gas discharge section (40) which discharges a vaporized material gas (VG) to a next process, characterized in that the vaporization section (20) comprises: a vaporizer main body (22) which transmits infrared rays from one side wall (22h) to the opposite side wall (22h) of the vaporization space (K) and is composed of a transparent member; a transparent spherical body (30) which is filled in the vaporization space (K) and transmits infrared rays; a heater (H) which is disposed so as to have a gap (d) of a width (M) with respect to the vaporizer main body (22) and which irradiates infrared rays to the vaporizer main body (22); and a reflection member (28) which has a mirror surface (28k) which reflects infrared rays on a surface opposite to the vaporizer main body (22) with the heater (H) interposed therebetween. An auxiliary reflection member (29) which has a mirror surface (29k) which reflects infrared rays on a surface opposite to the vaporizer main body (22) is provided on a surface of the heater (H) opposite to the vaporizer main body (22). The vaporizer main body (22) is composed of a pipe material which is formed in a spiral shape. A displacement gas supply section (25) which communicates with the gap (d) and supplies a displacement gas, and a displacement gas discharge section (26) which discharges the supplied displacement gas are provided in the vaporization section (20), and the gap (d) between the vaporizer main body (22) and the heater (H) becomes a passage of the displacement gas. The width (M) of the gap (d) is formed to be larger than the thickness (δ) of a temperature boundary layer (T) formed around the heater (H). ​ ​ ​ ​ 2. The gasifier of claim 1, wherein, ​ 3. The gasifier of claim 1, wherein, ​ 4. The gasifier of claim 1, wherein, ​ 5. The gasifier of claim 1, wherein, ​

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