Quartz nozzle and method of manufacturing the same

Abstract

To provide a quartz nozzle that can be used for supplying raw material gases and other purposes in a semiconductor deposition device and a method of manufacturing the same.SOLUTION: In a semiconductor deposition device, a quartz nozzle that is fused to the tip of a gas pipe for supplying a raw material gas and used is formed from synthetic quartz. The quartz nozzle 10 includes: a circular nozzle surface 11 with multiple discharge holes 12 formed for discharging the raw material gas; and a skirt portion 13 consisting of a side wall that is upright relative to the nozzle surface 11 on the periphery of the nozzle surface. The inner diameter D1 of the skirt portion 13 is the same as the inner diameter of the gas pipe to which the quartz nozzle 10 is mounted. The end face of the gas pipe made of quartz and the end face of the skirt portion of the quartz nozzle 10 are heated with an oxyhydrogen burner or the like, slightly melted and fused together. By providing the skirt portion in this way, the influence of heating during fusion on the nozzle surface 11 can be suppressed, thereby suppressing influence such as deformation or clogging of the discharge holes 12 due to heating.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a quartz nozzle that can be used for supplying source gases in a semiconductor film forming apparatus and for other purposes, and a method for manufacturing the same. [Background technology]

[0002] In semiconductor film formation equipment, quartz gas pipes and nozzles are sometimes used to supply source gases that are chemically stable even at high temperatures. Patent Document 1 discloses a quartz nozzle that supplies reactant gases from five gas holes in the vertical direction. Patent Document 2 discloses a quartz nozzle with 14 discharge holes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-313774 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-175995 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to eject the source gas in a rectified state without disturbance, it is conceivable to form a nozzle surface by providing a large number of holes in a quartz plate like a shower head. To join such a nozzle to a quartz gas pipe, a method of fusing the two together using an oxyhydrogen burner or the like can be used. However, this type of fusion process poses the problem of heat deformation of the nozzle surface and holes. While narrowing the holes is desirable for streamlining the flow of source gas, narrowing the holes can sometimes result in the holes becoming clogged due to deformation during fusion. Deformation or blockage of the holes disrupts the flow of source gas, creating vortices and causing variations in the semiconductor film thickness. Furthermore, deposition of reaction products can cause particles and crystal defects, hindering semiconductor film formation. In view of the above problems, the present invention aims to provide a quartz nozzle that is less susceptible to the effects of heat during fusion, and a method for manufacturing the same. [Means for solving the problem]

[0005] The present invention provides A quartz nozzle made of quartz is fused to the tip of a quartz gas pipe through which a gas flows, a nozzle surface having a plurality of ejection holes formed therein for ejecting the gas; a skirt portion formed of a side wall of a constant height standing upright on the nozzle surface so as to surround the entire periphery of the nozzle surface, The skirt portion may be a quartz nozzle having a shape that allows it to be fused to the end face of the gas pipe without any gaps.

[0006] According to the present invention, since the skirt portion is provided, the skirt portion and the gas pipe can be fused together, which reduces the effect of heat caused by fusion on the nozzle surface and prevents deformation of the discharge hole.

[0007] In the present invention, the shape and thickness of the nozzle surface, the shape, dimensions and arrangement of the ejection holes, the thickness and height of the skirt portion, etc. can be determined arbitrarily. For example, the gas pipe, nozzle surface, etc. may be circular. The nozzle surface is preferably flat in that ejection holes can be easily formed therein, but it may also be curved. The plurality of discharge holes may have the same shape and size, or may have a mixture of different shapes and sizes. From the viewpoint of achieving gap-free fusion bonding to the end face of the gas pipe, it is preferable that the shape of the skirt portion matches the shape of the end face of the gas pipe, particularly the shape of the inner circumference. Alternatively, the shape of the inner circumference of the skirt portion may be made to match the shape of the outer circumference of the gas pipe so that the skirt portion can be placed over the end face of the gas pipe like a lid.

[0008] In the present invention, The nozzle face and the skirt portion may be integrally formed.

[0009] This simplifies the construction of the quartz nozzle and also reduces the possibility of the flow of source gas being disturbed at the joint between the nozzle face and the skirt portion. However, this does not exclude the possibility of molding the nozzle face and the skirt portion as separate bodies and joining them together.

[0010] In the present invention, The quartz may be synthetic quartz.

[0011] While so-called fused silica can be fused at around 1200°C, synthetic silica can reach temperatures of approximately 1800°C or higher during fusion, making it more susceptible to the effects of heat. However, the present invention is highly useful in that it can suppress such effects.

[0012] In the present invention, The skirt portion may protrude from the nozzle surface by a height of 3 mm or more.

[0013] This makes it possible to further suppress the influence of heat on the nozzle surface when the skirt portion is fused.

[0014] In the present invention, The distance between the outermost discharge hole and the outer edge of the skirt portion may be 5 mm or more.

[0015] By doing so, even if the nozzle surface is affected by heat during fusion bonding, deformation of the ejection holes can be suppressed.

[0016] The present invention provides A method for manufacturing a quartz nozzle formed of quartz and fused to the tip of a quartz gas pipe through which a gas flows, comprising: (a) preparing a slurry containing quartz powder; (b) preparing a molding die corresponding to the shape of the quartz nozzle, the molding die having a nozzle surface in which a plurality of ejection holes for ejecting the gas are formed, and a skirt portion formed of a side wall of a constant height that stands upright on the nozzle surface so as to surround the entire periphery of the nozzle surface; (c) holding a pin or wire for forming the discharge hole in a state where the pin or wire penetrates the molding die; (d) mixing the slurry and a curing agent and injecting the mixture into the mold, and curing the mixture to form a molded article having the shape.

[0017] The quartz nozzle of the present invention can be manufactured in various ways, such as by cutting it out from a block of quartz, or by molding the nozzle surface and skirt surface separately and then joining them together. However, the above-mentioned method makes it possible to manufacture a quartz nozzle relatively easily and accurately without wasting material as occurs with cutting.

[0018] The present invention does not necessarily have to include all of the various features described above, and some of them may be omitted or combined as appropriate. It goes without saying that the various features described for the quartz nozzle can also be applied to the method for manufacturing the quartz nozzle. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 2 is an explanatory diagram showing the structure of a quartz nozzle. [Figure 2] FIG. 10 is an explanatory diagram showing a state in which a quartz nozzle is fused to a gas pipe. [Figure 3] FIG. 10 is an explanatory diagram showing a state in which a conventional quartz nozzle is fused to a gas pipe. [Figure 4] 10A and 10B are explanatory diagrams showing the structure of a modified quartz nozzle. [Figure 5] 1 is a flowchart showing a manufacturing process of a quartz nozzle. DETAILED DESCRIPTION OF THE INVENTION

[0020] Examples of the present invention will be described below. FIG. 1 is an explanatory diagram showing the structure of a quartz nozzle. In a semiconductor film formation apparatus, the nozzle is fused to the tip of a gas pipe for supplying source gas. In this embodiment, both the gas pipe and the quartz nozzle are made of synthetic quartz. Fused quartz may be used instead of synthetic quartz.

[0021] 1(a) is a perspective view of a quartz nozzle 10. The quartz nozzle 10 of the embodiment includes a circular nozzle surface 11 having a plurality of ejection holes 12 formed therein for ejecting a source gas, and a skirt portion 13 surrounding the nozzle surface 11 and formed of a side wall that stands upright relative to the nozzle surface 11. The corner where the nozzle surface 11 and the skirt portion are connected is chamfered 13a, but the chamfered edge 13a may be omitted.

[0022] FIG. 1(b) is a front view of the nozzle surface 11. In this embodiment, the nozzle surface 11 is a flat plate, but it may be a concave or convex curved surface. The shape, dimensions, and arrangement of the discharge holes 12 may also be For example, in the illustrated example, the ejection holes 12 are formed over almost the entire surface of the nozzle surface 11, but it is also possible to have no ejection holes 12 formed near the outer periphery, and in this case, it is preferable that the distance L1 (see FIG. 1(c)) between the outermost ejection hole 12 and the outer edge of the skirt portion 13 is 5 mm or more. 1(b) all have the same shape and size, it is acceptable for there to be a mixture of discharge holes 12 with different shapes and sizes. For example, there may be a plurality of discharge holes 12 with a diameter d≦1 mm.

[0023] 1(c) is a cross-sectional view taken along the A-A' cross section which includes the diameter of the nozzle surface 11. As already explained, a skirt portion 13 is provided on one side of the plate-shaped nozzle surface 11 having a thickness of t. The surface of the nozzle surface 11 on which the skirt portion 13 is provided will be referred to as the back surface, and the surface on which the skirt portion 13 is not provided will be referred to as the front surface. The height H1 (hereinafter sometimes simply referred to as "height") of the skirt portion 13 protruding from the nozzle surface 11 can be determined arbitrarily, but is preferably 3 mm or more. The overall thickness H2 of the quartz nozzle 10 is "height H1 + thickness t." H2 is preferably 3 mm or more, and more preferably 5 mm or more, 10 mm or more, 15 mm or more, or 20 mm or more. The distance L1 between the outermost discharge hole 12 and the outer edge of the skirt portion 13 is preferably 5 mm or more, and more preferably 7 mm or more, 10 mm or more, or 20 mm or more. Regarding the relationship between the thickness T and height H1 of the skirt portion 13, H1 / T is preferably 4 or more, and more preferably 6 or more, 10 or more, or 15 or more. It is not necessary to satisfy all of the above-mentioned numerical conditions, and some of them may be selected or combined.

[0024] A recess is formed on the rear side of the nozzle surface 11 by the skirt portion 13. The inner diameter D1 of the skirt portion 13 is the same as the inner diameter of the gas pipe to which the quartz nozzle 10 is attached. This prevents steps from occurring on the inner surface when the quartz nozzle 10 is attached to the gas pipe. In this embodiment, the outer diameter D2 of the skirt portion 13 is the same as the outer diameter of the gas pipe, but it may be different.

[0025] FIG. 2 is an explanatory diagram showing the state of fusing a quartz nozzle to a gas pipe. FIG. 2(a) is an explanatory diagram showing the state before fusing. The quartz nozzle 10 is fused by aligning the skirt portion 13 with the end face of the gas pipe 1 that conveys the source gas. The fusion is performed, for example, by heating both the end face of the gas pipe 1 and the end face of the skirt portion 13 with an oxyhydrogen burner or the like, slightly melting them, and joining them. Heating can be performed by various methods, but in the case of synthetic quartz, it is necessary to heat it up to about 1800°C, so it is preferable to use an oxyhydrogen burner.

[0026] 2(b) shows the fused state. As shown in the figure, at joint C, the gas pipe 1 and the skirt portion 13 of the quartz nozzle 10 are joined without any gaps. The inner diameter D1 of the skirt portion 13 (see FIG. 1(c)) is matched to the inner diameter of the gas pipe 1, so when they are joined as shown in FIG. 2(b), no step is formed on the inside, allowing the source gas to flow without turbulence. In this embodiment, the outer diameter D2 of the skirt portion 13 is matched to the outer diameter of the gas pipe 1, so they can be joined without any step in appearance as shown in FIG. 2(b).

[0027] Figure 3 is an explanatory diagram showing the state of a conventional quartz nozzle being fused to a gas pipe. Figure 3(a) shows the state before fusion. As shown in the figure, the conventional quartz nozzle 10A is composed of a plate-shaped nozzle surface 11A with discharge holes 12A formed therein, and does not have a skirt portion. In this state, the outer peripheries of the gas pipe 1 and the nozzle surface 11 are heated to fuse them. Figure 3(b) shows the fused state. The nozzle surface 11A is fused directly to the end face of the gas pipe 1 at joint C. However, with this method, the outer periphery of the nozzle surface 11A is heated, which melts the nozzle surface 11A, and the discharge holes 12 near the periphery may be deformed or blocked due to the effects of surface tension. While it is possible to heat the nozzle surface 11A in a way that does not deform the discharge holes 12, this reduces workability and may result in poor fusion.

[0028] According to the quartz nozzle 10 of this embodiment (see FIG. 2), as shown in FIG. 2, fusion can be performed by utilizing the skirt portion 13. Since it is the end face of the skirt portion 13 that is heated, the influence of heat on the discharge hole 12 can be suppressed. As explained above, the height of the skirt portion 13 can be determined arbitrarily, but if the height of the skirt portion 13 is set to 3 mm or more, there is an advantage in that the effects of heating the skirt portion 13 can be further suppressed. As explained above, the arrangement of the discharge holes 12 can be determined arbitrarily, but if the distance L1 between the outermost discharge hole 12 and the outer edge of the skirt portion 13 is set to 5 mm or more, it becomes possible to further avoid the effects of heat.

[0029] 4A and 4B are explanatory diagrams showing the structure of a modified quartz nozzle, in which Fig. 4A shows a perspective view of the state before fusion, and Fig. 4B shows a cross-sectional view of the quartz nozzle 10B. The quartz nozzle 10B of this modified example has an inner diameter D3 that is the same as the outer diameter D4 of the gas pipe 1. Therefore, the quartz nozzle 10B can be fused to the gas pipe 1 by placing it over the gas pipe 1 like a lid. This allows the gas pipe 1 to be fused to the back surface 11Bb of the nozzle surface 11B, as shown in FIG. 4(b). As a result, the possibility of a step occurring between the gas pipe 1 and the quartz nozzle 10B can be further reduced.

[0030] Figure 5 is a flowchart showing the manufacturing process of a quartz nozzle. It shows the method of pouring quartz slurry into a mold and letting it harden. First, the worker installs the pins and molds (step S10). The installation state is shown schematically in the figure. Molds M1 and M2 have holes formed in their bottom surfaces that correspond to the discharge holes 12. Pins P are installed so as to pass through these discharge holes 12 and remain vertical. Instead of pins, wires may be installed with sufficient tension applied to maintain linearity. The space N surrounded by molds M1 and M2 is the space in which the quartz nozzle is formed. The shape of the molds is not limited to the example shown in the figure, and various shapes and arrangements are possible.

[0031] Next, a slurry, which is a solution for forming a quartz nozzle, is poured through an inlet provided in the mold (step S11). The slurry can be composed of various components, for example, a solution containing silica glass powder, a curable resin, a binder, and pure water. A sol may also be used.

[0032] After the slurry is poured in this way, it is hardened in this state (step S12). Thereafter, the wire and the mold are removed (step S13), and a hardened body having a large number of discharge holes 12 formed at positions corresponding to the wire is formed, as shown in the figure. The hardened body is then dried, degreased, and vitrified (step S14), thereby forming a quartz nozzle.

[0033] The quartz nozzle can be manufactured by various methods other than the above. For example, it can be manufactured by cutting out a block of quartz. Alternatively, the nozzle face 11 and the skirt portion 13 can be formed separately and then joined together. However, the method shown in Figure 5 makes it possible to integrally mold a quartz nozzle with a nozzle face and skirt portion relatively easily without wasting material compared to these methods. It also makes it possible to form a large number of ejection holes with high precision, and it is also possible to reduce the diameter of the ejection holes.

[0034] In the above-described manufacturing method, wires and pins can be used arbitrarily. However, wires have the advantage that sufficient tension must be applied to maintain straightness, whereas pins do not require tension. Furthermore, pins do not require as large a device as wires, so they have the advantage of being able to accommodate an increased number of holes. On the other hand, when the hole diameter is very fine, pins may bend, and wires may be preferable. Wires and pins can be selected appropriately taking these factors into consideration.

[0035] For example, the two may be used according to the following criteria: In the following description, the hole diameter d and the overall thickness H2 of the quartz nozzle 10 (see FIG. 1) are used. (1) In the range of d≦0.3 mm, there is a risk of the pin bending, so wire is used. (2) When 0.3 mm≦d≦0.4 mm, either wire or pin can be selected. (3) If 0.4 mm≦d and H2 / d≦50, use a pin. (4) When 0.4 mm≦d and 50≦H2 / d≦100, either wire or pin can be selected. (5) When 0.4 mm≦d and 100≦H2 / d, wire is used. If a pin is used, it will be extremely thin and it will be difficult to maintain linearity. The above criteria are merely examples, and for example, this may be simplified to use a wire when d≦0.3 mm and a pin when 0.4 mm≦d. In addition, the two can be used differently based on various other criteria.

[0036] The above describes an embodiment of the present invention. The use of the quartz nozzle of this embodiment has the advantage that it can be fused to a gas pipe for supplying raw materials while avoiding deformation or clogging of the nozzle. Furthermore, the manufacturing method of this embodiment has the advantage that such a quartz nozzle can be manufactured easily and accurately. The present invention does not necessarily have to have all of the above-mentioned features, and some of them may be omitted or combined as appropriate. Furthermore, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made. The present invention is not limited to a quartz nozzle attached to a gas pipe for supplying source gases in a semiconductor film formation apparatus, and can also be used to supply various source gases. [Industrial Applicability]

[0037] The present invention can be utilized for a quartz nozzle that can be used for supplying source gases in a semiconductor film forming apparatus and for other purposes, and for a method of manufacturing the same. [Explanation of symbols]

[0038] 1. Gas pipe 10, 10A, 10B Quartz nozzle 11, 11A, 11B nozzle surface 11Bb back side 12, 12A discharge hole 13 Skirt Club 13a Chamfer

Claims

1. A quartz nozzle made of quartz is fused to the tip of a quartz gas pipe through which a gas flows, a nozzle surface having a plurality of ejection holes formed therein for ejecting the gas; a skirt portion formed of a side wall of a constant height standing upright on the nozzle surface so as to surround the entire periphery of the nozzle surface, The skirt portion of the quartz nozzle is shaped so that it can be fused to the end surface of the gas pipe without any gaps.

2. 2. The quartz nozzle according to claim 1, wherein the nozzle face and the skirt portion are integrally formed.

3. 2. The quartz nozzle according to claim 1, wherein said quartz is synthetic quartz.

4. 2. The quartz nozzle according to claim 1, wherein the skirt portion protrudes from the nozzle surface by a height of 3 mm or more.

5. 2. The quartz nozzle according to claim 1, wherein the distance between the outermost discharge hole and the outer edge of the skirt portion is 5 mm or more.

6. A method for manufacturing a quartz nozzle formed of quartz and fused to the tip of a quartz gas pipe through which a gas flows, comprising: (a) preparing a slurry containing quartz powder; (b) preparing a molding die corresponding to the shape of the quartz nozzle, the molding die including a nozzle surface having a plurality of ejection holes for ejecting the gas formed therein, and a skirt portion formed of a side wall of a constant height that stands upright on the nozzle surface so as to surround the entire periphery of the nozzle surface; (c) holding a pin or wire for forming the discharge hole in a state in which the pin or wire penetrates the molding die; (d) mixing the slurry and a curing agent and injecting the mixture into the mold, and curing the mixture to form a molded body having the shape.

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