Gas mixing device for semiconductor process and semiconductor process equipment

Abstract

The present invention discloses a gas mixing device for semiconductor processing, which comprises, from the upstream end to the downstream end, the following: a narrow hole defined in the body and having an upstream end and a downstream end; a buffer space defined in the body and having an upstream end and a downstream end, the upstream end fluid of the buffer space being connected to the downstream end of the narrow hole, and the width of the buffer space being greater than the width of the narrow hole; and a diverter plate having an upper surface and a lower surface, a plurality of diverter holes being formed between the upper and lower surfaces of the diverter plate, the plurality of diverter holes being connected to the downstream end of the buffer space. It is characterized in that a recess is formed on the upper surface of the diverter plate, and the recess is directly opposite to the downstream end of the narrow hole, so that the gas flow passing through the narrow hole hits the wall of the recess to form turbulence. In addition, the present invention also provides a semiconductor processing equipment.

Description

Technical Field

[0001] The present invention relates to a gas mixing device, in particular to a gas mixing device in a semiconductor process equipment, and more particularly to a gas mixing device connected to the upstream of a spray assembly. Background Art

[0002] The semiconductor manufacturing process may involve the use of multiple gases (or chemical sources). For example, the production of multilayer thin films requires the use of multiple gases. During the process, different gases are mixed and supplied to the wafer surface for reaction. The uniformity of the gas mixing determines the quality of the deposition on the wafer surface. Therefore, gas mixing devices are known to be developed and optimized for semiconductor processing equipment.

[0003] Figures 1A to 1C Illustration of the effect of gas mixing. Figure 1A The ideal mixing effect is shown, where the first gas flow (rightward arrow) and the second gas flow (leftward arrow) merge approximately in the center of the confluence space. This is because the pressures of the two gases are comparable and their flow paths correspond. Figure 1B This shows the actual mixing effect, where the pressure of one gas is greater than the other, causing the two gases to mix primarily at the edges of the confluence space. Figure 1C This shows another possible mixing effect that may occur in practice, where the gas flows are not aligned and parallel to each other, resulting in misalignment of the two gases at the junction and inadequate mixing.

[0004] Chinese patent publication number CN110917914A discloses a gas mixing device that receives and mixes two gases, and supplies the mixed gas to a spray assembly of a semiconductor process equipment. The gas mixing device includes a first guide member, a second guide member, and a diverter plate. The first guide member is responsible for receiving and supplying the first gas, and the second guide member is connected to the downstream of the first guide member and is responsible for receiving and supplying the first gas from the first guide member. The second guide member is also responsible for receiving and supplying the second gas. The diverter plate is connected to the downstream of the second guide member, so that the two together define a confluence channel for the first gas and the second gas to mix here. With the gas mixing device, the first gas and the second gas can be pre-mixed before entering the semiconductor process chamber, thereby improving the mixing effect.

[0005] However, the structural design of the aforementioned gas mixing device is extremely complex, resulting in high manufacturing and processing costs. Subsequent replacement or maintenance of the device requires disassembly, making the maintenance process complex and relatively expensive. Furthermore, the gas flow path of the aforementioned gas mixing device still has numerous blind spots, preventing adequate gas mixing. Therefore, in order to produce higher-quality semiconductor thin films and reduce production costs to enhance product competitiveness, it is necessary to develop a gas mixing device with a simple structural design that is suitable for various semiconductor process equipment. Summary of the Invention

[0006] The present invention aims to provide a gas mixing device and semiconductor process equipment for semiconductor processing to solve the problem of poor gas mixing in the prior art.

[0007] The present invention provides a gas mixing device for semiconductor processes, comprising: a body having an upstream end and a downstream end. The body comprises, in order, the following between the upstream and downstream ends: a narrow hole defined in the body and having an upstream end and a downstream end; a buffer space defined in the body and having an upstream end and a downstream end, the upstream end of the buffer space being fluidically connected to the downstream end of the narrow hole, and the width of the buffer space being greater than the width of the narrow hole; and a diverter plate having an upper surface and a lower surface, a plurality of diverter holes formed between the upper and lower surfaces of the diverter plate, the plurality of diverter holes being fluidically connected to the downstream end of the buffer space, a recess formed on the upper surface of the diverter plate, the recess facing the downstream end of the narrow hole, thereby causing airflow passing through the narrow hole to collide with the wall of the recess, thereby forming turbulent flow.

[0008] The beneficial effect of the gas mixing device of the semiconductor process is that the recess is directly opposite to the downstream end of the narrow hole, so that the airflow passing through the narrow hole hits the wall of the recess to form turbulence, thereby improving the gas mixing effect and thus improving the uniformity of deposition.

[0009] Furthermore, the width of the upstream end of the narrow hole is greater than the width of the downstream end of the narrow hole.

[0010] Furthermore, the cavity is formed by an inwardly concave curved surface on the upper surface of the diverter plate.

[0011] Furthermore, the width of the downstream end of the narrow hole is smaller than a maximum width of the recess.

[0012] Furthermore, the plurality of diversion holes surround the recess.

[0013] Furthermore, the body includes a first plate and a second plate, the first plate defines the narrow hole and the buffer space, and the second plate defines the plurality of diversion holes and the recess.

[0014] The present invention also provides a semiconductor process equipment, comprising: a spray component for supplying a mixed gas to a wafer surface; a gas mixing tube, fluidically connected to the spray component and supplying the mixed gas; and the gas mixing device, fluidically connected to the gas mixing tube, for mixing a first gas and a second gas.

[0015] Furthermore, the center of the gas mixing tube, the center of the narrow hole and the center of the recess are coaxial.

[0016] Furthermore, the narrow hole is configured to receive the first gas and the second gas in the gas mixing tube, and the plurality of diverter holes are configured to divert the mixed gas back to the downstream end of the gas mixing tube.

[0017] Further, the recess is configured to have a relatively higher Reynolds number than the narrow hole when gas mixing occurs.

[0018] Furthermore, the positions of the narrow hole and the recess enable gas mixing to occur primarily in the center of the gas mixing tube.

[0019] The technical effect of the semiconductor process equipment is to ensure that the first gas (such as a precursor) and the second gas (such as a process gas) are mixed at the center of the channel, and the turbulence generation means of the gas mixing device further improves the gas mixing effect, thereby improving the uniformity of deposition. The spatial configuration of the gas mixing device of the present invention enables the gases to be actively mixed. In addition, the composition structure of the gas mixing device of the present invention is relatively simple, and the practicality (such as ALD equipment) and applicability of reactants are also good. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention may be further understood with reference to the following figures and descriptions. Non-limiting and non-exhaustive examples are described with reference to the following figures. The components in the figures are not necessarily to actual size; the emphasis is on illustrating the structure and principles.

[0021] Figures 1A to 1C Schematic diagrams illustrating the gas mixing effects, showing ideal mixing, actual mixing, and staggered mixing, in order.

[0022] Figure 2 A schematic diagram showing an embodiment of the semiconductor process equipment of the present invention.

[0023] Figure 3 A schematic diagram showing an embodiment of the gas mixing device of the present invention. DETAILED DESCRIPTION

[0024] The present invention will be more fully described below with reference to the accompanying drawings, illustrating specific exemplary embodiments. However, the claimed subject matter may be embodied in many different forms, and thus the construction of the claimed subject matter is not limited to any exemplary embodiment disclosed herein; the exemplary embodiments are provided for illustrative purposes only. Similarly, the present invention is intended to provide a reasonably broad scope for the claimed subject matter.

[0025] The use of the phrase "in one embodiment" in this specification does not necessarily refer to the same embodiment, and the use of "in other (some) embodiments" in this specification does not necessarily refer to different embodiments. For example, the claimed subject matter includes all or some combinations of exemplary embodiments.

[0026] Figure 2 Figure 2 The schematic diagram of the semiconductor process equipment of the present invention mainly includes a chamber sidewall 1, an upper cover 2 connected to the top of the sidewall 1, a spray assembly 3 fixed to the bottom of the upper cover 2, and a wafer support plate 4 surrounded by the sidewall 1 and located below the spray assembly 3. A bottom (not shown) is also connected to the bottom of the sidewall 1, so that the sidewall 1, the bottom and the inner side of the spray assembly 3 define a chamber in the chamber. Although not shown, it should be understood that other components are configured on the top of the upper cover 2, such as a radio frequency connection device for electrical connection to the spray assembly 3. The downstream end of a gas mixing pipe 5 is fixed to the top of the upper cover 2 and is fluidically connected to the spray assembly 3 through the air inlet of the upper cover 2, so that a mixed gas enters the diffusion space of the spray assembly 3 and the spray plate and is supplied to the chamber. The inner side of the sidewall 1 is also configured with an annular channel 6 connected to an external exhaust system for exhausting the chamber gas.

[0027] The upstream end of the gas mixing tube 5 is fluidically connected to a first pipeline supplying the first gas and a second pipeline supplying the second gas. In other words, the gas mixing tube 5 serves as a confluence of the first and second pipelines, meaning that the first and second gases meet and mix within the gas mixing tube 5. The first and second pipelines can each be equipped with a flow controller and corresponding valves to monitor and control the gas flow rates within the first and second pipelines.

[0028] The gas mixing device 7 of the present invention is fluidically connected to the gas mixing tube 5. As shown, the gas mixing device 7 is a segment of the gas mixing tube 5. Alternatively, the gas mixing device 7 is housed within the passageway of the gas mixing tube 5. Although the first and second gases meet in the gas mixing tube 5 before passing through the gas mixing device 7, they are not fully mixed. The gas mixing device 7 provides a turbulence-generating mechanism and allows gas mixing to occur in the center of the gas mixing tube 5, improving mixing efficiency.

[0029] The above configuration is only for the purpose of explaining this embodiment and is not intended to limit the present invention. For example, more or fewer components may be present in the chamber, the gas mixing device 7 may be located at another position in the gas supply line, such as closer to the upstream end or the downstream end, or the gas mixing device 7 may be located between the spray assembly 3 and the gas mixing pipe 5. Figure 2 Only part of the cavity configuration is shown, but based on the symmetry of the cavity, those skilled in the art should be able to understand other parts that are not shown.

[0030] Figure 3 The gas mixing device 7 of the present invention is shown. It has a main body composed of a first plate 71 and a second plate 72. The main body has an upstream end and a downstream end. The upstream end herein refers to the end that receives gas or is relatively close to the gas source, while the downstream end refers to the end that discharges gas or is relatively close to the spray assembly. The upstream end of the main body is removably connected to a first section 51 of the gas mixing pipe 5, and the downstream end of the main body is removably connected to a second section 52 of the gas mixing pipe 5.

[0031] The first plate 71 is located at the upstream end of the body and is removably connected to the first section 51. The first plate 71 has an upstream end and a downstream end. A narrow hole 711 is formed at the upstream end of the first plate 71. The narrow hole 711 is defined by an inclined surface extending from the upstream end to the downstream end, making the narrow hole 711 a tapered hole, but the present invention is not limited to this. The narrow hole 711 has a width W1. Regardless of whether the width W1 refers to the maximum width at the upstream end or the minimum width at the downstream end, the width W1 is less than the channel width of the first section 51. In other words, the pressure of the first gas and the second gas increases after entering the narrow hole 711 from the first section 51.

[0032] The first plate 71 has a buffer space 712 formed at its downstream end, which is fluidically connected to the narrow hole 711. The buffer space 712 is a cylindrical space defined by an annular inner wall of the first plate 71 and has a width (diameter, W2). The width W2 is greater than the width W1 of the narrow hole 711. The first gas and the second gas released through the narrow hole 711 can diffuse in the buffer space 712.

[0033] The second plate 72 has an upper surface and a lower surface, wherein the upper surface is detachably connected to the downstream end of the first plate 71, and the lower surface is detachably connected to the second section 52. The upper surface of the second plate 72 is exposed to the buffer space 712 and faces the downstream end of the narrow hole 711, so that the upper surface of the second plate 72 can be subjected to the high-pressure impact of the first gas and the second gas. A recess 721 is formed on the upper surface of the second plate 72. The recess 721 is fluidically connected to the buffer space 712 and faces the downstream end of the narrow hole 711. The width W3 of the recess is greater than the minimum width of the narrow hole 711 so that the first gas and the second gas released through the narrow hole 711 can impact the inner wall of the recess 721 as much as possible. The recess 721 is defined by the concave curve of the upper surface, but the present invention is not limited to this. In other words, the recess described in the present invention may refer to a surface that sinks from a flat surface.

[0034] A plurality of diverter holes 722 extend between the upper and lower surfaces of the second plate 72 and penetrate the second plate 72. The upstream ends of the diverter holes 722 are fluidically connected to the buffer space 712 to supply the mixed gas in the buffer space 712 downwardly to the channel of the second section 52. The diverter holes 722 are arranged in a manner surrounding the recess 721, but the present invention is not limited to this.

[0035] Referring to FIG. 1 , the gas mixing tube 5 has a central axis C. Figure 2 The narrow hole 711, buffer channel 712, and recess 721 are shown coaxially arranged, meaning that the centers of the narrow hole 711, the buffer channel 712, and the recess 721 are coaxial with the central axis C. In other words, the central axis C passes through the narrow hole 711, the buffer channel 712, and the recess 721. In this arrangement, the first and second gases passing through the narrow hole 711 are released at high pressure and impact the surface of the recess 721 on the upper surface of the second plate 72. The surface of the recess 721 rebounds the gases, creating turbulence and causing mixing between the narrow hole 711 and the recess 721. This mixing occurs approximately on the central axis C, achieving ideal mixing results.

[0036] This turbulent flow creates a strong disturbance in the first and second gases, enhancing mixing. Furthermore, experimental and simulation results show that the Reynolds number measured at the recess 721 or in the area between the narrow hole 711 and the recess 721 is higher than in other areas, indicating a significant turbulent flow and effective gas mixing. Furthermore, the first and second plates 71, 72 of the gas mixing device 7 of the present invention are relatively simple in structure, resulting in relatively low maintenance costs.

Claims

1. A gas mixing device for semiconductor processing, characterized in that: include: A body having an upstream end and a downstream end, wherein the upstream end and the downstream end sequentially comprise: a narrow hole defined in the body and having an upstream end and a downstream end, the upstream end of the narrow hole being configured to receive the first gas and the second gas; a buffer space defined in the body and having an upstream end and a downstream end, the upstream end of the buffer space being fluidically connected to the downstream end of the narrow hole, and a width of the buffer space being greater than a width of the narrow hole; and a diverter plate having an upper surface and a lower surface, a plurality of diverter holes being formed between the upper surface and the lower surface of the diverter plate, the plurality of diverter holes being fluidly connected to the downstream end of the buffer space, wherein a recess is formed on the upper surface of the diverter plate, and the recess is directly opposite to the downstream end of the narrow hole, thereby causing the airflow passing through the narrow hole to hit the wall of the recess and be rebounded to form turbulence.

2. The gas mixing device according to claim 1, characterized in that: The width of the upstream end of the narrow hole is greater than the width of the downstream end of the narrow hole.

3. The gas mixing device according to claim 1, characterized in that: The cavity is formed by an inwardly concave curved surface on the upper surface of the diverter plate.

4. The gas mixing device according to claim 1, characterized in that: The width of the downstream end of the narrow hole is smaller than a maximum width of the recess.

5. The gas mixing device according to claim 1, characterized in that: The plurality of diversion holes surround the cavity.

6. The gas mixing device according to claim 1, characterized in that: The main body includes a first plate and the diverter plate. The first plate defines the narrow hole and the buffer space, and the diverter plate defines the plurality of diverter holes and the recess.

7. A semiconductor process equipment, characterized in that: include: a spray assembly for supplying a mixed gas to a wafer surface; a gas mixing pipe, the gas mixing pipe being fluidically connected to the spray assembly and supplying the mixed gas; The gas mixing device according to claim 1, wherein the gas mixing device is fluidically connected to the gas mixing pipe and is used to mix a first gas and a second gas.

8. The semiconductor process equipment according to claim 7, wherein: The center of the gas mixing tube, the center of the narrow hole and the center of the cavity are coaxial.

9. The semiconductor process equipment according to claim 7, wherein: The narrow hole is configured to receive the first gas and the second gas in the gas mixing tube, and the plurality of diversion holes are configured to divert the mixed gas back to the downstream end of the gas mixing tube.

10. The semiconductor process equipment according to claim 7, wherein: The recess is configured to have a relatively higher Reynolds number than the narrow hole when gas mixing occurs.

11. The semiconductor process equipment according to claim 7, wherein: The positions of the narrow hole and the recess enable gas mixing to occur mainly in the center of the gas mixing tube.

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