Gas injector

Abstract

To provide a gas injector.SOLUTION: A gas injector and an apparatus constructed and arranged to process a plurality of substrates in a process chamber with such a gas injector may be disclosed. The gas injector may be used to provide a process gas into the process chamber. The gas injector may have a primary conduit elongated along a main axis and a feed end at one end constructed and arranged to connect to a process gas line of the apparatus. There may be provided a plurality of secondary conduits connected with their first end to the primary conduit substantially perpendicular to the main axis of the primary conduit and being provided with a gas exhaust opening at a second end of the secondary conduit to provide the process gas into the process chamber.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure may relate to gas injectors and apparatus constructed and arranged to process a plurality of substrates using such gas injectors. The gas injectors may be used to provide process gas into a process chamber. The gas injector may have a main tube elongated along a main axis and an inlet at one end constructed and arranged to connect to a process gas line of the apparatus. [Background technology]

[0002] During processes such as atomic layer deposition (ALD), epitaxy, and chemical vapor deposition (CVD), precursors, which may be in gaseous form, may be provided to a substrate. These precursors are often stored in a vessel or reservoir that is transported via a gas injector to the process chamber to react with the substrate. To improve the reactivity of the precursors in the process chamber, a plasma may be provided.

[0003] ALD manufacturing processes typically involve pulsing precursors with gas injectors into a process chamber, reacting them with the substrate surface, and then purging the chamber before introducing the next precursor. For the reaction efficiency of the precursor in the process chamber, the concentration throughout the process chamber can be important. Summary of the Invention

[0004] This Summary is provided to introduce a selection of concepts in a simplified form that are described in more detail below in the Detailed Description of Example Embodiments of the Disclosure. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0005] It may be an object to provide gas injectors and devices with improved efficiency.

[0006] Thus, a gas injector may be provided for providing process gas into a process chamber of an apparatus configured and arranged, in use, to process a plurality of substrates. The gas injector may comprise a main tube elongated along a major axis and an inlet at one end configured and arranged to connect to a process gas line of the apparatus. A plurality of secondary tubes are connected at their first ends to the main tube substantially perpendicular to the major axis of the main tube and are provided with a gas outlet at second ends of the secondary tubes to provide process gas into the process chamber.

[0007] This Summary is provided to introduce a selection of concepts in a simplified form that are described in more detail below in the Detailed Description of Example Embodiments of the Disclosure. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0008] While the specification concludes with claims particularly pointing out and distinctly claiming what are regarded as the embodiments, the advantages of the embodiments of the present disclosure may be more readily ascertained from the description of certain specific examples of the embodiments of the present disclosure when read in conjunction with the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic cross-sectional side view of a gas injector. [Diagram 2] FIG. 2 is a schematic cross-sectional bottom view of the gas injector of FIG. 1. [Diagram 3] 2 is a schematic cross-sectional side view of the gas injector of FIG. 1, illustrating its position relative to a substrate. [Figure 4] 2 is a schematic cross-sectional view of an apparatus constructed and arranged to process a plurality of substrates using the gas injector of FIG. 1; [Diagram 5] 5 is a schematic cross-sectional top view of a gas injector showing its position relative to the substrate in the apparatus of FIG. 4. [Figure 6]5 is a schematic cross-sectional top view of a gas injector in the apparatus of FIG. 4 as it is moved above the substrate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale, for example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of the illustrated embodiments of the present disclosure.

[0011] Although certain specific embodiments and examples are disclosed below, it will be understood by those skilled in the art that the invention extends beyond the specifically disclosed embodiments and / or uses of the invention, and obvious modifications and equivalents thereof, and therefore it is not intended that the scope of the disclosed invention should be limited by the specific disclosed embodiments described below.

[0012] The illustrations presented herein are not meant to be the actual appearance of any particular materials, structures, or devices, but merely idealized representations used to describe embodiments of the present disclosure.

[0013] The particular implementations shown and described are illustrative of the invention and its best mode and are not intended to otherwise limit the scope of aspects and implementations in any way. Indeed, for the sake of brevity, conventional manufacturing, association, preparation, and other functional aspects of the system may not be described in detail. Furthermore, the connecting lines shown in the various figures are intended to represent example functional relationships and / or physical couplings between the various elements. Many alternative or additional functional relationships or physical connections may be present in an actual system and / or may not be present in some embodiments.

[0014] It should be understood that the configurations and / or approaches described herein are exemplary in nature, and that these specific embodiments or examples are not to be taken in a limiting sense, as numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. Thus, the various illustrated operations may be performed in the order illustrated, in other orders, or omitted in some cases.

[0015] 1 is a schematic cross-sectional side view of a gas injector according to one embodiment. In use, the gas injector 1 may be used to provide process gas into a process chamber of an apparatus configured and arranged to process a plurality of substrates. The gas injector 1 may comprise a main tube 3 elongated along a main axis 4 parallel to a Z-axis. At one end, the main tube 3 may comprise a supply tip 7 configured and arranged to connect to a process gas line (not shown) of the apparatus.

[0016] The gas injector 1 may comprise a number of secondary pipes 5. The secondary pipes 5 may be connected to a main pipe 3. The secondary pipes may be connected to the main pipe 3 at a first end 9 substantially perpendicular to a major axis of the main pipe. The secondary pipes 5 may be provided with a gas outlet 11 at a second end 13 of the secondary pipe 5 for providing process gas into the process chamber.

[0017] FIG. 2 is a schematic cross-sectional bottom view of the gas injector 1 of FIG. 1, showing the gas outlet 11. The secondary tube 5 may have a curved shape 15 in a plane substantially perpendicular to the main axis of the primary tube 3. The plane may be parallel to the X, Y axes. In use, the plane may correspond to a horizontal plane in which a substrate is positioned in the apparatus. The gas outlet 11 may be at the bottom surface of the secondary tube 5. In this way, the gas outlet 11 may provide process gas to an upper surface of a substrate positioned below.

[0018] The curved shape 15 may form a part of a generally circular shape having a radius of 8-22 cm, preferably 12-18 cm, about the first axis 12. The first axis 12 may be substantially parallel to the main axis 4 of the main tube 3 and may extend in the Z direction. The secondary tube 5 may have a length from the first end 9 to the second end 13 of 8-22 cm, preferably 12-18 cm. In use, the first axis 12 may correspond to the vertical Z axis of the apparatus, perpendicular to the plane in which the substrate is positioned in the apparatus. The first axis 12 may be positioned near the centre of the substrate to be positioned in the apparatus.

[0019] Returning to Figure 1, the main pipe 3 may have a branching portion 16 connected to a plurality of secondary pipes 5. The main pipe 3 may have a non-branching portion 19 constructed and arranged to connect the branching portion 16 to the supply end 7. The non-branching portion 19 may have a length of 10 to 40, preferably 15 to 30 cm.

[0020] Figure 3 is a schematic cross-sectional side view of the gas injector 1 of Figure 1 showing its position relative to a substrate 17. As shown, the gas outlet 11 may be at the bottom surface of the secondary tube 5. In this manner, the gas outlet 11 may provide process gas to the upper surface of a substrate 17 positioned therebelow.

[0021] The number of secondary tubes 5 may be equal to the number of substrates 17 to be processed in the process chamber. Although only 13 substrates are illustrated, the present invention is not limited to this number of substrates. The number of secondary tubes 5 may be 2-201, preferably 25-151, and most preferably 50-101.

[0022] The secondary tubes 5 may be spaced apart along the main tube 3 at substantially the same distance along the major axis. The same distance may be between 0.4 and 5 cm, more preferably between 0.6 and 4 cm, and most preferably between 0.8 and 3 cm. The secondary tubes 5 may be provided along a substantially straight line along the major axis of the main tube 3.

[0023] Figure 4 is a schematic cross-sectional view of an apparatus constructed and arranged to process a plurality of substrates using the gas injector 1 of Figure 1. In this figure, a process tube 18 is shown defining a process chamber 20. The furnace may include a vertically movable door 22 configured to close a central inlet opening 24 in lower and upper flanges 26. The upper and lower flanges 26 may partially close an open end of the process tube 18. A liner 30 may extend along the process tube 18 to protect the tube.

[0024] The vertically movable door 22 may also be configured to support a wafer boat 28 configured to hold a plurality of substrates 17 supported on a pedestal 32. The wafer boat 28 may have a plurality of boat rails 21. The boat rails 21 may be provided with spaces to form edges for supporting the substrates 17 in the wafer boat 28.

[0025] The vertically movable door 22 may be provided with a drive 27 allowing a rotation 29 of the wafer boat 28 in the process chamber 20. This rotation may allow to improve the thermal uniformity of the substrates 17 in the boat 28. Between the drive 27 and the wafer boat 28, a pedestal 32 may be provided with a heater and / or insulation, which may allow to further improve the thermal uniformity. The liner 30 may be closed at the top end, for example in a dome shape, and may be substantially closed against the gas above the inlet opening 24.

[0026] The gas injector 1 may be disposed within a process chamber 20 that extends substantially vertically beyond the height of a wafer boat 28. A liner 30 extending along the process tube 18 may have a radially outwardly extending bulge 31 to accommodate the gas injector 1.

[0027] The first precursor provided to the feed end 7 of the gas injector 1 may be a sublimated solid metal precursor. The apparatus may be configured to provide the sublimated solid metal precursor from a precursor container to the process chamber.

[0028] The first precursor provided to the feed end 7 of the gas injector 1 may be a vaporized metal chloride. The metal chloride may be selected from titanium tetrachloride (TiCl4), vanadium tetrachloride (VCl4), molybdenum pentachloride (MoCl5), molybdenum dioxide dichloride (MoO2Cl2), niobium pentachloride (NbCl5), tantalum pentachloride (TaCl5), aluminum trichloride (AlCl3), hafnium tetrachloride (HfCl4), and zirconium tetrachloride (ZrCl4). The apparatus may be configured to provide the vaporized metal precursor from a precursor container to the process chamber.

[0029] The gas injector 1 may include a supply end 7 operably connected to a first supply line 34, which may be connected to a second source of a first precursor 36. The supply end 7 may be operably connected to a second supply line (not shown), which may be connected to a second source containing nitrogen for purging or a second precursor for treatment.

[0030] The second precursor provided at the supply end 7 of the gas injector 1 may include ammonia. The first precursor and the second precursor may react with each other on the substrate 17 to form a metal nitride on the surface of the substrate 17.

[0031] The apparatus may be provided with a pump connection 38 for feeding gases from the process chamber 20 .

[0032] Figure 5 is a schematic cross-sectional top view of the gas injector 1 of Figure 1 showing its position relative to a substrate 17. The secondary tube 5 may be provided with a bottom-side gas exhaust at the second end 13 for providing process gas into the process chamber, but this is not visible in this top view.

[0033] The secondary tube 5 may have a curved shape in a plane substantially perpendicular to the major axis of the primary tube 3. The plane may be parallel to the X, Y axes and may correspond to the horizontal plane in which the substrate 17 is positioned in the apparatus in use.

[0034] The curved shape may form a portion of a generally circular shape having a radius of 8 to 22 cm, preferably 12 to 18 cm, about the first axis 12. The first axis 12 may be substantially parallel to the main axis 4 of the main tube 3. The first axis 12 may be positioned near the center of a substrate 17 positioned in the apparatus.

[0035] The secondary tube 5 may have a length from the first end 9 to the second end 13 of 8 to 22 cm, preferably 12 to 18 cm. This may correspond to the radius of the substrate 17 used by the device.

[0036] The substrates 17 may be mounted in the apparatus on a wafer boat 28 (see FIG. 4) having a number of boat rails 21. The boat rails 21 may be provided with spaces to provide edges for supporting the substrates 17 in the wafer boat.

[0037] A liner 30 may extend along the process tube 18 to protect the tube. The liner 30 extending along the process tube 18 may have a bulge 31 extending radially outward. The bulge 31 may accommodate the gas injector 1 when it is retracted from the substrate 17 as in FIG. 5. Retraction of the gas injector 1 may be required when a vertically movable door 22 (see FIG. 4) supporting a wafer boat 28 having a plurality of substrates 17 thereon may be moved up to place the substrates 17 into the process chamber 20.

[0038] The vertically movable door 22 may be provided with a drive 27 that allows for rotation 29 of the wafer boat 28 in the process chamber 20. The wafer boat 28 may have multiple boat rails 21 for supporting the substrates 17 in the wafer boat 28. Retraction of the gas injectors 1 may be required when the wafer boat 28 is rotated to avoid the boat rails 21 contacting the gas injectors 1.

[0039] When the vertically movable door 22 is closed and the boat rail 21 is out of the way of the gas injector 1, the gas injector 1 may be moved in a rotational direction 39 (about the Z axis) as shown in Figure 6. Figure 6 is a schematic cross-sectional top view of the gas injector of Figure 1. The gas exhaust (not shown) may be movable above the substrate 17 by rotating 39 the secondary tube 5 with an actuator operably connected to a controller (not shown).

[0040] A gas exhaust (not shown) may be movable above the center of the substrate 17. This may have the advantage that the concentration of precursors may be higher at the center of the substrate 17 and lower in the areas surrounding the substrate 17 in the process chamber 20. This may improve the process speed and / or precursor usage efficiency since the precursors are faster and more concentrated at the center of the substrate 17. Providing precursors from the side and relying on diffusion to reach the center of the substrate may take a lot of time.

[0041] The apparatus may be provided with a bearing constructed and arranged to mount a rotatable gas injector 1 in the apparatus. The bearing may enable the gas injector 1 to rotate 39 substantially about a main axis to move the gas outlet between the substrates 17. The bearing may be provided at the supply end 7 (in FIG. 1 ) of the gas injector 1. This has the advantage that the temperature and precursor concentration at the lower end may be lower so that there is less risk of reactions with the precursors which would disturb the bearing.

[0042] Alternatively, the gas injector 1 may move linearly using linear bearings, however, more space may be required to accommodate the gas injector 1 in its retracted position within the bulge 31 of the liner 30 when moving linearly away.

[0043] The gas injector 1 may be provided with a cooler (not shown) to cool the gas injector 1. The main pipe 3 may be provided with a cooler to cool the main pipe 3. The secondary pipe 5 may be provided with a cooler to cool the secondary pipe. The cooler may comprise a cooling line constructed and arranged to flow a cooling fluid through the gas injector 1 independent of the process gas. The cooling line may be part of a cooling circuit in which the cooling fluid is recirculated.

[0044] Cooling of the gas injector 1 may lead to non-uniformity in the temperature of the substrates 17 in the process chamber 20. To mitigate this, the wafer boat 28 and the substrates 17 that may be supported thereon may be rotated with the aid of a drive 27 operatively connected to a controller (not shown). Retraction of the gas injector 1 may be required as the wafer boat 28 rotates to avoid the boat rail 21 contacting the gas injector 1. The controller may be programmed to calculate position information of the boat rail 21 as a function of boat rotation 29, and the actuator may be controlled to move the gas injector 1 from its position between the substrates 17 as the boat rail 21 approaches the gas injector 1.

[0045] The gas exhaust port 11 has a diameter of at least 1 to 200 mm. 2 , preferably 4 to 100 mm 2 , preferably 10 to 50 mm 2 Optionally, the secondary tube 5 may be provided with a number of gas exhaust ports 11 along its length.

[0046] The gas injector 1 may be made of ceramic. The ceramic may be selected from silicon carbide (SiC), silicon oxide (SiOx), silicon, or aluminum oxide (AlOx). Optionally, the gas injector 1 may be made of metal.

[0047] Although illustrative embodiments of the invention have been described above, in part with reference to the accompanying drawings, it should be understood that the invention is not limited to these embodiments. Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

[0048] Throughout this specification, a reference to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification do not necessarily refer to the same embodiment. Furthermore, it is noted that particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner to form new embodiments not expressly described. [Explanation of symbols]

[0049] 1 Gas injector 3 main manager 4 spindle 5 Secondary pipe 7 Supply end 9 First End 11 Gas exhaust port 12 First axis 13 Second end 15 Curved Shape 16 Branch 17 Substrate 18 Process Tube 19 Non-branched section 20 Process Chamber 21 Boat Rail 22 Doors 24 Inlet opening 26 Flange 27 Drive unit 28 Wafer Boat 29 rotations 30 Liner 31 Bulge 32 Pedestal 34 First Supply Line 36 First Precursor 38 Pump connection 39 Rotation Direction

Claims

1. 1. A gas injector for providing a process gas into a process chamber of an apparatus constructed and arranged to process a plurality of substrates, comprising: a main pipe elongated along a major axis, the main pipe having a feed end at one end thereof, the feed end constructed and arranged to be connected to a process gas line of the apparatus; a plurality of secondary pipes connected at first ends to the main pipe substantially perpendicular to the main axis of the main pipe and having gas exhaust ports at second ends of the secondary pipes for providing the process gas into the process chamber.

2. 2. The gas injector of claim 1, wherein the secondary tube has a curved shape in a plane substantially perpendicular to the major axis of the primary tube.

3. 3. The gas injector of claim 2, wherein the curved shape substantially forms a part of a generally circular shape centered on a first axis substantially parallel to the main axis of the main tube and having a radius of 8 to 22 cm, preferably 12 to 18 cm.

4. 2. A gas injector as claimed in claim 1, wherein the secondary tube has a length from the first end to the second end of between 8 and 22 cm, preferably between 12 and 18 cm.

5. 2. The gas injector of claim 1, wherein the main pipe has branched portions connected to the plurality of secondary pipes and a non-branched portion constructed and arranged to connect the branched portions to the supply end, the non-branched portion having a length of 10-40, preferably 15-30 cm.

6. 2. The gas injector of claim 1, wherein the number of said plurality of sub-tubes is between 2 and 201, preferably between 25 and 151, and most preferably between 50 and 101.

7. 2. The gas injector of claim 1, wherein the plurality of secondary tubes are spaced apart from one another along the main tube at substantially the same distance along the major axis.

8. The gas injector of claim 1 , wherein the plurality of secondary pipes are provided along a substantially straight line along the major axis of the main pipe.

9. The gas injector of claim 1 , wherein the gas injector is provided with a cooler for cooling the gas injector.

10. 10. The gas injector of claim 9, wherein the main pipe is provided with a cooler for cooling the main pipe.

11. 11. The gas injector of claim 10, wherein the secondary pipe is provided with a cooler for cooling the secondary pipe.

12. 1. An apparatus constructed and arranged to process a plurality of substrates, comprising: a process tube creating a process chamber; 13. An apparatus comprising: a door configured to support a wafer boat having a plurality of substrates in the process chamber, the apparatus being provided with the gas injector of claim 1.

13. The apparatus of claim 12 , wherein the gas injector is constructed and arranged to be moveable in the apparatus to allow the gas outlet to be moved between the substrates.

14. 13. The apparatus of claim 12, wherein the process tube is provided with a liner, the liner being provided with a bulge constructed and arranged to provide space within the process tube for retracting the gas injector.

15. 13. The apparatus of claim 12, wherein the wafer boat is constructed and arranged to process a number of substrates equal to the number of sub-tubes of the gas injector.

16. The apparatus of claim 12 , wherein the apparatus is configured to provide a sublimated solid metal precursor from a precursor container to the process chamber.

17. The device is a titanium tetrachloride (TiCl ４ ), vanadium tetrachloride (VCl ４ ), molybdenum pentachloride (MoCl ５ ), molybdenum dioxide dichloride (MoO ２ C ２ ), niobium pentachloride (NbCl ５ ), Tantalum Pentachloride (TaCl ５ ), aluminum trichloride (AlCl ３ ), hafnium tetrachloride (HfCl ４ ), and zirconium tetrachloride (ZrCl ４ 13. The apparatus of claim 12 configured to provide to the process chamber a vaporized metal chloride selected from:

18. 1. An apparatus constructed and arranged to process a plurality of substrates, comprising: a process tube creating a process chamber; a gas injector having a gas outlet for providing a process gas into the process chamber; an apparatus comprising: a door configured to support a wafer boat having a plurality of substrates in the process chamber, the gas injector being configured and arranged to be movably disposed in the apparatus to enable an actuator operably connected to a controller to move the gas exhaust port between the substrates.

19. 20. The apparatus of claim 18, wherein the gas injector is provided with a cooler for cooling the gas injector, the wafer boat is provided with a boat rail for supporting the substrates in the wafer boat, and the apparatus is provided with a drive operably connected to the controller and constructed and arranged to rotate the wafer boat.

20. 20. The apparatus of claim 19, wherein the controller is programmed to calculate boat rail position information as a function of boat rotation, and the actuator is controlled to move the gas injector from the position between the substrates when the boat rail approaches the injector.

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