Gas mixing structure and gas uniformizing device

Abstract

The utility model provides a gas mixing structure and a gas uniformizing device. The gas mixing structure comprises a shell and a gas mixing part, the gas mixing part is located in the shell, and a gas inlet cavity is formed between the gas mixing part and the shell; the shell is provided with a plurality of air inlets; the gas mixing part comprises a pipe wall and a mixing cavity defined by the pipe wall, and through holes are formed in the pipe wall of the gas mixing part; gas enters the gas inlet cavity from the gas inlet and then enters the mixing cavity through the through holes in the pipe wall to be mixed. The gas uniformizing device comprises a cavity and the gas mixing structure, the gas mixing structure is located at the top of the cavity, the gas mixing part of the gas mixing structure extends out of the shell and extends into the cavity through the top of the cavity, and gas enters the gas mixing structure, is mixed by the gas mixing part and then enters the cavity. According to the gas mixing structure and the gas uniformizing device, the gas mixing uniformity can be improved, a film layer on a wafer grows continuously and uniformly, and the film forming uniformity is improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular to a gas mixing structure and a gas homogenizing device. Background Art

[0002] During the chemical vapor deposition (CVD) film growth process in semiconductor manufacturing, poor uniformity or discontinuity is common, especially when the growth location is small and the film thickness is very thin. This manifests as poor resistance uniformity, which affects the continuity of film growth in subsequent processes, causing damage to the metal layer and leading to more defects. The distribution uniformity of the reaction gases in this process has a significant impact on film uniformity, and gas uniformity is primarily determined by the gas inlet structure in the gas homogenizer.

[0003] The existing air intake structure generally has two air intake holes set on the side wall. The two streams of reaction gases with large flow rates directly collide with each other, resulting in an eccentric mixing of the reaction gases when they enter the cavity from the air intake structure, causing a higher gas concentration in a certain part of the wafer. For example, when looking down at the wafer from top to bottom, the gas concentration is higher in the lower left corner of the wafer, which will cause more thin film to be deposited on the corresponding part of the wafer surface. In addition, due to the influence of airflow, the corresponding air intake holes in the lower left corner of the bottom of the air intake structure may be clogged by deposition or particles. These problems cause uneven gas entry into the chamber, which in turn leads to poor film formation uniformity on the wafers in the chamber.

[0004] Therefore, a new air intake structure and air uniformity device are needed to solve the problem of uneven air mixing caused by eccentricity during air mixing, which in turn leads to poor uniformity in wafer film formation in the chamber. Utility Model Content

[0005] In view of the shortcomings of the prior art described above, the purpose of this application is to provide a gas mixing structure and a gas uniformity device to solve the problem of uneven gas mixing caused by the eccentricity of the gas intake structure during gas mixing in the prior art, which in turn leads to poor uniformity in wafer film formation in the chamber.

[0006] On the one hand, an embodiment of the present application provides a gas mixing structure, comprising a shell and a gas mixing section; the gas mixing section is located inside the shell, and an air intake cavity is formed between the gas mixing section and the shell; the shell is provided with a plurality of air intake ports; the gas mixing section comprises a tube wall and a mixing cavity surrounded by the tube wall, and the tube wall of the gas mixing section is provided with a through hole; after the gas enters the air intake cavity from the air intake port, it enters the mixing cavity through the through hole in the tube wall for mixing.

[0007] In some embodiments, the air inlet chamber is divided into several sub-air inlet chambers by a partition layer, and the several sub-air inlet chambers are not connected to each other. Each of the sub-air inlet chambers is connected to the mixing chamber by the through hole. Different reaction gases enter the mixing chamber from different sub-air inlet chambers through the through holes and are mixed.

[0008] In some embodiments, each of the sub-inlet cavities is configured with at least one inlet port.

[0009] In some embodiments, the plurality of sub-inlet chambers include a first sub-inlet chamber and a second sub-inlet chamber, wherein the first sub-inlet chamber is located above the second sub-inlet chamber, the first sub-inlet chamber is for the first gas to pass through, and the second sub-inlet chamber is for the second gas to pass through.

[0010] In some embodiments, the plurality of through holes are randomly distributed.

[0011] In some embodiments, the gas mixing portion includes an extension portion extending from the bottom of the shell.

[0012] In some embodiments, the extension is a straight-through pipe.

[0013] On the other hand, an embodiment of the present application provides a gas homogenizing device, comprising a chamber and a gas mixing structure as described in any one of the above items, wherein the gas mixing structure is located at the top of the chamber, and the gas mixing portion of the gas mixing structure extends out of the shell and extends into the chamber through the top of the chamber, and the gas enters the gas mixing structure and then enters the chamber after being mixed by the gas mixing portion.

[0014] In some embodiments, the gas uniformizing device includes a gas uniformizing structure, which is located between the gas mixing structure and the chamber and is used to allow the gas to enter the chamber uniformly.

[0015] As described above, the gas mixing structure and gas homogenizing device of the present application have the following beneficial effects: on the one hand, the gas mixing structure of the present application includes a shell and a gas mixing part, and the gas enters the gas inlet cavity from the gas inlet on the shell, and is first screened through the through holes in the tube wall of the gas mixing part, and then enters the gas mixing cavity of the gas mixing part, so that the different gases are mixed more evenly. On the other hand, the gas homogenizing device of the present application includes a chamber and the above-mentioned gas mixing structure, and the evenly mixed gas is passed into the chamber through the gas mixing part of the gas mixing structure. The gas mixing structure and gas homogenizing device of the present application can improve the uniformity of gas mixing, so that the film layer on the wafer in the chamber grows evenly, thereby improving the uniformity of film formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following figures describe in detail exemplary embodiments disclosed in this application. Like reference numerals denote similar structures throughout the several views of the drawings. Those skilled in the art will appreciate that these embodiments are non-limiting, exemplary embodiments, and that the drawings are provided for illustration and description purposes only and are not intended to limit the scope of this application. Other embodiments may also achieve the inventive intent of this application. It should be understood that the drawings are not drawn to scale.

[0017] in:

[0018] Figure 1 is a schematic diagram of a gas mixing structure according to some embodiments of the present application;

[0019] Figure 2 is a schematic perspective view of the appearance of a housing according to some embodiments of the present application;

[0020] Figure 3 is a three-dimensional schematic diagram of a separation layer according to some embodiments of the present application;

[0021] Figure 4 is a front cross-sectional schematic diagram of a gas mixing structure according to some embodiments of the present application;

[0022] Figure 5 Schematic diagram of a gas homogenizing device according to some embodiments of the present application. DETAILED DESCRIPTION

[0023] The following description provides specific application scenarios and requirements of the present application, with the purpose of enabling those skilled in the art to make and use the content of this application. Various local modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of this application. Therefore, this application is not limited to the embodiments shown, but is intended to be of the widest scope consistent with the claims.

[0024] refer to Figure 1 , an embodiment of the present application provides a gas mixing structure 10, including a shell 1 and a gas mixing section 2. The gas mixing section 2 is located in the shell 1, and an air inlet chamber 12 is formed between the gas mixing section 2 and the shell 1. The shell 1 is provided with a plurality of air inlets 11. The gas mixing section 2 includes a tube wall 21 and a mixing chamber 22 surrounded by the tube wall 21, and the tube wall 21 of the gas mixing section is provided with a through hole 23. After the gas enters the air inlet chamber 12 from the air inlet 11, it enters the mixing chamber 22 through the through hole 23 on the tube wall 21 for mixing. The flow rate of the gas when entering the air inlet chamber 12 from the air inlet 11 is relatively large. The setting of the air inlet chamber 12 and the gas mixing section 2 can buffer the airflow, avoiding the direct collision of the airflow after entering from the air inlet 11, causing uneven mixing. While the original reaction gas penetrates into the mixing chamber 22 through the through hole 23 on the tube wall 21, the reaction gas can also be screened through the through hole 23. Specifically, after the reaction gas fills the air inlet chamber 12, the gas pressure inside the air inlet chamber 12 is greater than the gas pressure inside the mixing chamber 22. Therefore, the reaction gas in the air inlet chamber 12 can diffuse into the mixing chamber 22 through the through hole 23. After the sieved reaction gas enters the mixing chamber 22, it becomes relatively stable and is easier to mix evenly in the mixing chamber 22.

[0025] Figure 21 is a perspective view of the housing 1, which is provided with an air inlet 11. It should be noted that the number and position of the air inlets 11 in the figure are for illustration only and are not limited to two, and can be provided according to actual needs.

[0026] The technical solution of this application is described in detail below with reference to the embodiments and drawings.

[0027] Further, refer to Figure 3 and Figure 4 As shown, in some embodiments, the air inlet chamber 12 is divided into several sub-air inlet chambers 122 by a partition layer 121, and the several sub-air inlet chambers 122 are not connected to each other. Each sub-air inlet chamber 122 is connected to the mixing chamber 22 by a through hole 23, and the number of through holes 23 in each sub-air inlet chamber 122 can be different, depending on specific needs. Different reaction gases first enter the different sub-air inlet chambers 122 that are isolated from each other, and then diffuse smoothly into the mixing chamber 22 through the through holes 23 before being mixed. The reaction gas is screened through the through holes 23, which can make the gas flow smaller and more uniform, easier to mix together, and help to improve the uniformity of the mixed gas. The partition layer 121 is snap-fitted and sealed to the shell 1 to form several annular, sealed sub-air inlet chambers 122. The number of layers of the partition layer 121 is set according to the specific process requirements.

[0028] In some embodiments, each sub-inlet cavity 122 is configured with at least one inlet port 11. Different reactant gases enter different sub-inlet cavities 122 through different inlet ports 11. That is, one inlet port 11 corresponds to one sub-inlet cavity 122, and several sub-inlet cavities 122 form several annular sealed spaces. The number of inlet ports 11 can be determined based on the number of gas types that need to enter the same sub-inlet cavity 122.

[0029] In some embodiments, the plurality of sub-inlet chambers 122 include a first sub-inlet chamber 1221 and a second sub-inlet chamber 1222. The first sub-inlet chamber 1221 is located above the second sub-inlet chamber 1222. The first sub-inlet chamber 1221 allows the flow of a first gas, while the second sub-inlet chamber 1222 allows the flow of a second gas. In some embodiments, the first gas comprises hydrogen, and the second gas comprises dicobalt hexacarbonyl. The first and second gases are isolated and diffuse into the mixing chamber 22 through the through-holes 23 before mixing. For example, the first gas is hydrogen (H2) and argon (Ar), and the second gas is dicobalt hexacarbonyl (CCTBA) and argon (Ar), wherein argon is a diluent gas. Since dicobalt hexacarbonyl is an organic substance and has a certain degree of adhesion, it may remain on the inner wall of the tube wall 21 after entering the mixing chamber 22 from the second sub-inlet chamber 1222 and become a source of particle pollution. Therefore, the inlet chamber 12 is designed as an upper and lower sub-inlet chamber 122. After H2 and Ar enter the mixing chamber 22 from the upper first sub-inlet chamber 1221, they diffuse downward, which can take away some of the dicobalt hexacarbonyl adhering to the inner wall of the tube wall 21 and improve the uniformity of the reaction gas mixing.

[0030] In some embodiments, the distribution of the through holes 23 is random. In some embodiments, the apertures of the through holes 23 may also be different. Different numbers of through holes 23 and different apertures can be selected according to different gas properties and different process requirements. For example, the reaction gases hydrogen and dicobalt hexacarbonyl are gases of different properties, requiring different numbers of through holes 23 and different apertures. Alternatively, one process requires a hydrogen flow rate of 8 sccm (Standard Cubic Centimeters Per Minute), and another process requires a hydrogen flow rate of 6 sccm. Different apertures can be selected according to the flow specifications required by different processes.

[0031] In some embodiments, the through hole 23 may also be provided with a screen or other forms to act as an air intake screen, so that the gas entering the mixing chamber 22 is more stable.

[0032] In some embodiments, the gas mixing unit 2 includes an extension portion 24, which extends from the bottom of the housing 1. In some embodiments, the extension portion 24 is a straight-through pipe without an air intake screen, which can increase air intake efficiency.

[0033] The gas mixing structure 10 of the present application places the air inlet screen function (i.e., the through hole 23) in front of the pipe wall 21 of the mixing chamber 22, sieving the reaction gas before mixing, controlling the flow of the reaction gas, so that the reaction gas entering the mixing chamber 22 is mixed smoothly, and the uniformity of the gas mixing is improved. At the same time, the mixed gas output end extension 24 of the mixing chamber 22 is set as a straight-through pipeline to obtain a higher reaction chamber 101 (refer to Figure 5)Intake efficiency.

[0034] Specifically, in some embodiments, in the process of growing a metal cobalt (Co) film, an upper and lower sub-gas inlet chamber structure is adopted. The reaction gas hydrogen (H2) and the dilution gas argon (Ar) are introduced from the gas inlet 11 of the upper sub-gas inlet chamber 1221, and the reaction gas dicobalt hexacarbonyl (CCTBA) and the dilution gas argon (Ar) are introduced from the gas inlet 11 of the lower sub-gas inlet chamber 1222. After the reaction gases hydrogen and dicobalt hexacarbonyl enter their respective corresponding sub-gas inlet chambers 122, they are screened through the through holes 23 of the tube wall 21 and then smoothly diffused into the mixing chamber 22. Thereafter, they are evenly mixed in the mixing chamber 22 and then enter the reaction chamber 101 through the extension portion 24. On the other hand, the dicobalt hexacarbonyl (CCTBA) in this example is an organic substance with a certain degree of adhesion, and may remain on the inner wall of the pipeline and become a source of particle pollution. Therefore, in the gas mixing structure 10 with upper and lower sub-inlet chambers, hydrogen and argon are introduced into the upper sub-inlet chamber 1221, and dicobalt hexacarbonyl and argon are introduced into the lower sub-inlet chamber 1222. The hydrogen and argon can carry away some of the particle pollution sources adhered to the inner wall of the pipe wall 21. At the same time, the extension portion 24 is a straight pipeline, which can enable the gas to reach the reaction chamber quickly and unimpeded.

[0035] refer to Figure 5 As shown, in some embodiments, the present application further provides a gas uniformity device 100, comprising a chamber 101 and a gas mixing structure 10. The gas mixing structure 10 is located at the top of the chamber 101, and the gas mixing portion 2 of the gas mixing structure 10 extends out of the shell 1 and extends into the chamber 101 through the top of the chamber 101. After the gas enters the gas mixing structure 10, it is mixed in the gas mixing portion 2 and then enters the chamber 101. The gas mixing structure 10 improves the uniformity of the reaction gas mixing, so that the film layer on the surface of the wafer 103 in the chamber 101 grows uniformly, and reduces the resistance uniformity (RSU) value, wherein the lower the RSU value, the better the resistance uniformity of the wafer.

[0036] In some embodiments, the gas homogenizing device 100 includes a gas homogenizing structure 102. The gas homogenizing structure 102 is located between the gas mixing structure 10 and the chamber 101 and is configured to uniformly distribute gas into the chamber 101. The gas, uniformly mixed by the gas mixing structure 10, is first passed into the gas homogenizing structure 102 of the gas homogenizing device 100 for further homogenization before entering the chamber 101.

[0037] In some embodiments, the gas homogenization structure 102 includes a barrier layer 1021 and a shower head 1022. The mixed gas entering the chamber 101 passes through the barrier layer 1021 and then through the shower head 1022 to reach the top of the wafer 103, further ensuring the uniformity of the mixed reaction gas reaching the surface of the wafer 103, thereby achieving uniform film growth on the surface of the wafer 103.

[0038] The beneficial effects that may be brought about by the embodiments of the present application include, but are not limited to: a gas mixing structure and gas homogenizing device of the present application, which utilizes an air inlet chamber structure, causing the reactant gas to reside in the air inlet chamber before entering the gas mixing section. The reactant gas is then screened through the through-holes in the gas mixing section tube wall and diffused into the mixing chamber, thereby stabilizing the reactant gas and achieving a more uniform gas mixture. The uniform reactant gas enters the reaction chamber directly and quickly through the straight-through pipe of the extension portion 24, greatly improving the gas intake efficiency, enabling more uniform film growth on the wafer, and thus improving the level of the wafer film formation process.

[0039] It should be noted that different embodiments may produce different beneficial effects. In different embodiments, the beneficial effects that may be produced may be any one or a combination of the above, or any other possible beneficial effects.

[0040] The basic concepts have been described above. It will be apparent to those skilled in the art that the detailed disclosure above is merely illustrative and does not limit this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and revisions to this application. Such modifications, improvements, and revisions are suggested in this specification and remain within the spirit and scope of the exemplary embodiments of this application.

[0041] It should be noted that, in the description of this application, unless otherwise expressly specified or limited, the terms "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections, electrical connections; rotational connections, or sliding connections; direct connections, or indirect connections through an intermediate medium; and can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application in light of specific circumstances.

[0042] In addition, when terms such as "first", "second", and "third" are used in the specification of this application to describe various features, these terms are only used to distinguish these features and cannot be understood as indicating or implying the relationship between the features, the relative importance, or implicitly indicating the number of features indicated.

[0043] In addition, this specification describes exemplary embodiments by reference to idealized exemplary cross-sectional views and / or plan views and / or perspective views. Therefore, differences from the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are foreseeable. Therefore, the exemplary embodiments should not be interpreted as limited to the shapes of the regions shown herein, but should include deviations in shapes due to, for example, manufacturing. Therefore, the regions shown in the figures are schematic in nature, and their shapes are not intended to illustrate the actual shapes of the regions of the device nor to limit the scope of the exemplary embodiments.

[0044] At the same time, this application uses specific terms to describe the embodiments of this specification. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a certain feature, structure, or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment," "an embodiment," or "an alternative embodiment" mentioned twice or multiple times in different locations in this application does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the present application may be appropriately combined.

[0045] Similarly, it should be noted that, in order to simplify the presentation of this application and thus facilitate understanding of one or more embodiments of the invention, the foregoing descriptions of the embodiments of this application sometimes combine multiple features into a single embodiment, figure, or description thereof. However, this disclosure method does not mean that the subject matter of this application requires more features than those recited in the claims. In fact, an embodiment may have fewer features than all of the features of a single embodiment disclosed above.

[0046] Finally, it should be understood that the embodiments described in this application are merely illustrative of the principles of the embodiments of this application. Other variations may also fall within the scope of this application. Therefore, by way of example and not limitation, alternative configurations of the embodiments of this application may be considered consistent with the teachings of this application. Accordingly, the embodiments of this application are not limited to the embodiments explicitly introduced and described in this application.

Claims

1. A gas mixing structure, characterized in that: It includes a shell and a mixing part; the mixing part is located inside the shell, and an air inlet cavity is formed between the mixing part and the shell; the shell is provided with a plurality of air inlets; the mixing part includes a tube wall and a mixing cavity surrounded by the tube wall, and the tube wall of the mixing part is provided with through holes; after the gas enters the air inlet cavity from the air inlet, it enters the mixing cavity through the through holes in the tube wall for mixing.

2. The gas mixing structure according to claim 1, characterized in that: The air inlet chamber is divided into several sub-air inlet chambers by a partition layer. The several sub-air inlet chambers are not connected to each other. Each sub-air inlet chamber is connected to the mixing chamber by the through hole. Different reaction gases enter the mixing chamber from different sub-air inlet chambers through the through holes and are mixed.

3. The gas mixing structure according to claim 2, characterized in that: Each of the sub-inlet cavities is configured with at least one inlet port.

4. The gas mixing structure according to claim 3, characterized in that: The plurality of sub-air inlet chambers include a first sub-air inlet chamber and a second sub-air inlet chamber, wherein the first sub-air inlet chamber is located above the second sub-air inlet chamber, the first sub-air inlet chamber is for the first gas to pass through, and the second sub-air inlet chamber is for the second gas to pass through.

5. The gas mixing structure according to claim 1, characterized in that: The distribution of the plurality of through holes is random.

6. The gas mixing structure according to claim 1, characterized in that: The gas mixing portion includes an extension portion extending from the bottom of the shell.

7. The gas mixing structure according to claim 6, characterized in that: The extension portion is a straight-through pipeline.

8. A gas homogenizing device, characterized in that: It comprises a chamber and the gas mixing structure according to any one of claims 1 to 7, wherein the gas mixing structure is located at the top of the chamber, the gas mixing portion of the gas mixing structure extends out of the shell and extends into the chamber through the top of the chamber, and the gas enters the gas mixing structure and then enters the chamber after being mixed by the gas mixing portion.

9. The gas homogenizing device according to claim 8, characterized in that: It includes a gas uniformity structure, which is located between the gas mixing structure and the chamber and is used to make the gas enter the chamber uniformly.

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