Gas spray header and deposition equipment

Abstract

The utility model provides a gas spray header and deposition equipment, the gas spray header comprises an outer ring, a plurality of first gas holes extending in the height direction are distributed in the outer ring, and the first gas holes are communicated with the top surface of the outer ring and the bottom surface of the outer ring; the inner ring is arranged in the outer ring, a plurality of second air holes extending in the height direction are distributed in the inner ring, the second air holes are communicated with the top face of the inner ring and the bottom face of the inner ring, and the height of the inner ring is larger than that of the outer ring so that the bottom face of the inner ring can protrude downwards relative to the outer ring. By adjusting the gas flow, the deposition rate of the inner ring and the deposition rate of the outer ring are basically consistent, and the uniformity of the film is optimized.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor product preparation equipment, and in particular to a gas shower head and deposition equipment. Background Art

[0002] When using a tungsten metal deposition equipment to process a wafer, the gas showerhead on the equipment is used to provide the gas required for the process to ensure that the wafer can contact the process gas to complete the process. Figure 1 As shown, the gas shower head 2' is provided with regularly arranged air holes 20', which are arranged in a concentric circle manner. The process gas is introduced into the cavity through the air holes 20', which can ensure that the wafer reacts with the process cavity during the process to complete the process. Figure 1 In the figure, only the black dots are used to exemplarily represent the positions of the pores 20'. Figure 2 As shown, there are four identical gas shower heads 2' on the mounting surface 1 of the deposition equipment. The functions of the gas shower heads 2' at different positions are different. The upper left is the first gas shower head, the upper right is the second gas shower head, the lower left is the third gas shower head, and the lower right is the fourth gas shower head. Among them, the air holes of the third gas shower head and the fourth gas shower head are connected to the gas supply pipeline. When the process is carried out, the wafer is placed on the base normally, and the gas required for the process is provided to the cavity through the air holes, and a reaction occurs on the surface of the wafer, thereby depositing a thin film. When the process is carried out, the edge minimum coverage ring (MOER) is used to protect the edge of the wafer to prevent tungsten metal from being deposited on the back of the wafer. However, the existence of the edge minimum coverage ring will also affect the deposition rate at the edge of the wafer, resulting in the film thickness of the edge thinner than the inner circle, that is, the outer circle of the film is thin and the inner circle is thick. The difference in thickness will affect the uniformity of the film, resulting in discontinuity of the deposited tungsten metal at the edge, affecting the electrical properties of the contact hole. Utility Model Content

[0003] In view of the problems in the prior art, the purpose of the present application is to provide a gas shower head and a deposition device to adjust the gas flow rate so that the deposition rates of the inner circle and the outer circle are basically consistent, thereby optimizing the uniformity of the thin film.

[0004] The present application provides a gas shower head for a deposition device, wherein the gas shower head comprises:

[0005] An outer ring, wherein a plurality of first air holes extending in a height direction are distributed inside the outer ring, and the first air holes communicate with a top surface of the outer ring and a bottom surface of the outer ring;

[0006] The inner ring is arranged inside the outer ring, and a plurality of second air holes extending in the height direction are distributed inside the inner ring, and the second air holes connect the top surface of the inner ring and the bottom surface of the inner ring. The height of the inner ring is greater than the height of the outer ring, so that the bottom surface of the inner ring protrudes downward relative to the outer ring.

[0007] In some embodiments, the length of the airway in the second pore is 1.2 to 1.8 times the length of the airway in the first pore.

[0008] In some embodiments, a plurality of third air holes extending in the height direction are provided at the junction between the inner ring and the outer ring, and the third air holes connect the top surface of the junction and the bottom surface of the junction.

[0009] In some embodiments, the third air holes are evenly arranged in a circle along the circumference of the junction.

[0010] In some embodiments, the aperture of the third pore is larger than the aperture of the first pore and the aperture of the second pore.

[0011] In some embodiments, the aperture of the first pore is the same as the aperture of the second pore, and the aperture of the third pore is 2 to 4 times the aperture of the first pore.

[0012] In some embodiments, a bottom surface of the junction corresponding to the position of the third air hole is provided with a slope, and the slope is inclined upward from the inside to the outside.

[0013] In some embodiments, the first air holes and the second air holes are arranged in a plurality of concentric circles.

[0014] In some embodiments, the top surface of the inner ring is flush with the top surface of the outer ring.

[0015] An embodiment of the present application further provides a deposition device, comprising a plurality of gas shower heads, wherein at least one of the gas shower heads adopts the structure of the above-mentioned gas shower head.

[0016] The gas shower head and deposition equipment provided by the present application have the following advantages:

[0017] By adopting the gas shower head structure of the present application, since the height of the inner ring is greater than the height of the outer ring, and the length of the airway in the second air hole is greater than the length of the airway in the first air hole, the gas flow rate in the second air hole of the inner ring can be reduced, so that the gas flow rates of the inner and outer rings are the same. By adjusting the gas flow rate, the deposition rates of the inner and outer rings are basically the same, the uniformity of the thin film is optimized, and the electrical properties of the outer ring contact holes can be optimized, so that the yield of the product is improved, the production efficiency is promoted, and the reliability of the product is greatly guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings.

[0019] Figure 1 It is a schematic diagram of providing a plurality of gas through holes in a gas shower head;

[0020] Figure 2 is a schematic diagram of four gas shower heads arranged in a deposition apparatus;

[0021] Figure 3 is a schematic structural diagram of a gas shower head according to an embodiment of the present application;

[0022] Figure 4 is a bottom view of a gas shower head according to another embodiment of the present application;

[0023] Figure 5 yes Figure 4 Magnified view of the mestomata A.

[0024] Reference numerals:

[0025] 1 Deposition equipment mounting surface 22 Inner ring

[0026] 2' Existing gas shower head 221 Second air hole

[0027] 20' Existing air hole 23 Junction

[0028] 2 Gas shower head 231 Third air hole

[0029] 21 Outer ring 232 Slope

[0030] 211 First pore DETAILED DESCRIPTION

[0031] The example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in a variety of forms and should not be construed as being limited to the embodiments set forth herein; on the contrary, these embodiments are provided so that the present application will be comprehensive and complete, and the concept of the example embodiments will be fully conveyed to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated descriptions will be omitted. "Or" and "or" in the specification may both mean "and" or "or". Although the terms "upper", "lower", "between", etc. may be used in this specification to describe different exemplary features and elements of the present application, these terms are used herein only for convenience, such as according to the directions of the examples described in the accompanying drawings. Nothing in this specification should be construed as requiring a specific three-dimensional direction of the structure to fall within the scope of the present application. Although "first" or "second" etc. are used in this specification to represent certain features, they are only used to represent the function, and are not used as a limitation on the number and importance of specific features.

[0032] As described above, when the deposition device in the prior art deposits a thin film on the surface of a wafer, due to the existence of the minimum edge coverage ring, the thickness of the inner and outer circles of the thin film is inconsistent, which affects the uniformity of the thin film. In order to solve the technical problems in the prior art, the present application provides a gas shower head for a deposition device and a deposition device including the same. The gas shower head includes an outer ring and an inner ring. The outer ring is arranged outside the inner ring. A plurality of first air holes extending in the height direction are distributed inside the outer ring, and the first air holes are connected to the top surface of the outer ring and the bottom surface of the outer ring. A plurality of second air holes extending in the height direction are distributed inside the inner ring, and the second air holes are connected to the top surface of the inner ring and the bottom surface of the inner ring. The height of the inner ring is greater than the height of the outer ring, so that the bottom surface of the inner ring protrudes downward relative to the outer ring. The embodiment of the present application also provides a deposition device including the gas shower head, and the deposition device includes a plurality of gas shower heads, wherein at least one gas shower head adopts the above-mentioned structure in which the height of the inner ring and the outer ring are inconsistent. Specifically, which gas shower head or heads in the deposition device adopts the structure in which the inner circle and the outer circle have inconsistent heights can be selected as needed. For example, the third gas shower head and the fourth gas shower head of the existing deposition device are designed to have a gas shower head structure in which the inner circle height is greater than the outer circle height, but the present application is not limited to this.

[0033] By adopting the present application, since the height of the inner circle is greater than that of the outer circle, the length of the airway in the second air hole is greater than that in the first air hole. When other conditions are basically the same, the longer the airway, the smaller the flow rate. Therefore, the gas flow rate in the second air hole of the inner circle can be reduced, so that the gas flow rate of the inner and outer circles is the same. By adjusting the gas flow rate, the deposition rates of the inner and outer circles are basically the same, the uniformity of the thin film is optimized, and the electrical properties of the outer circle contact holes can be optimized, so that the yield of the product is improved, the production efficiency is promoted, and the reliability of the product is greatly guaranteed.

[0034] The structure of the gas shower head in a specific embodiment is described below in conjunction with the accompanying drawings. It should be understood that the accompanying drawings and the following description are only examples and are not intended to limit the scope of protection of the present application.

[0035] like Figure 3 As shown, in one embodiment of the present application, the gas shower head includes an outer ring 21 and an inner ring 22. The outer ring 21 is arranged outside the inner ring 22. A plurality of first air holes 211 extending in the height direction are distributed inside the outer ring 21, and the first air holes 211 are connected to the top surface of the outer ring 21 and the bottom surface of the outer ring 21. A plurality of second air holes 221 extending in the height direction are distributed inside the inner ring 22, and the second air holes 221 are connected to the top surface of the inner ring 22 and the bottom surface of the inner ring 22. The height of the inner ring 22 is greater than the height of the outer ring 21, so that the bottom surface of the inner ring 22 protrudes downward relative to the outer ring 21. Since the height of the inner ring 22 is greater than the height of the outer ring 21, the air passage length in the second air holes 221 is greater than the air passage length in the first air holes 211. In this embodiment, the top surface of the inner ring 22 is flush with the top surface of the outer ring 21, and the gas pressure at the top surface of the inner ring 22 and the top surface of the outer ring 21 is the same. Since the apertures of the first pore 211 and the second pore 221 are relatively small, Figure 3 The positions of the first air holes 211 and the second air holes 221 are schematically indicated by dots.

[0036] There are three main factors that affect the gas flow rate: 1. The length of the gas pipeline, 2. The pressure difference, and 3. The shape of the pores. When other conditions are basically the same, the longer the gas channel, the smaller the flow rate. In the present application, since the pressure at each position of the gas shower head is consistent, the pressure difference does not affect the gas shower head. The length of the gas channel in the second pore 221 is greater than the length of the gas channel in the first pore 211, so that the gas flow rate in the second pore 221 of the inner ring 22 can be reduced, so that the gas flow rate passing through the inner ring 22 and the outer ring 21 is the same. By adjusting the gas flow rate, the deposition rates of the inner ring 22 and the outer ring 21 are basically the same, and the uniformity of the film is optimized. The electrical properties of the contact holes of the outer ring 21 can be optimized, the yield of the product is improved, the efficiency of production is promoted, and the reliability of the product is greatly guaranteed.

[0037] In this embodiment, the outer ring 21 is arranged at the edge of the inner ring 22. The airway length in the second air hole 221 is 1.2 to 1.8 times the airway length in the first air hole 211, and can be 1.5 times, but the present application is not limited thereto. Since the second air hole 221 and the first air hole 211 both extend in the height direction, the ratio of the airway length in the second air hole 221 to the airway length in the first air hole 211 is substantially equal to the ratio of the height of the inner ring 22 to the height of the outer ring 21. In practical applications, the ratio of the height of the inner ring 22 to the height of the outer ring 21 can be selected as needed, and is not limited to the values ​​listed here.

[0038] In this embodiment, the first pores 211 and the second pores 221 are arranged in a plurality of circles in the form of concentric circles, and the aperture of the first pores 211 is the same as the aperture of the second pores 221, which is generally about 1 mm. The aperture and distribution of the first pores 211 and the second pores 221 can be the same as those of existing pores, but the present application is not limited thereto.

[0039] When the deposition equipment with the gas shower head is used to start the process, the process gas passes through the top of the gas shower head. There are dense air holes arranged in concentric circles below the inner ring 22 and the outer ring 21. The upper and lower air holes of the inner ring 22 and the outer ring 21 are connected. Since the airway length of the second air hole 221 of the inner ring 22 is greater than the airway length of the first air hole 211 of the outer ring 21, the flow rate of the gas passing through is lower than that of the outer ring 21. At this time, the gas passing through the outer ring 21 reaches the wafer surface earlier than the inner ring 22. The process reaction of the outer ring 21 of the wafer balances the part missing due to the minimum edge coverage ring before, which will make the deposition rate of the outer ring 21 consistent with that of the inner ring 22. The uniformity of the entire wafer is guaranteed.

[0040] Figure 4 and Figure 5Schematic diagram of the structure of the gas shower head of another embodiment of the present application. After the height of the inner ring 22 is increased so that the gas passage length of the second air hole 221 is greater than the gas passage length of the first air hole 211, due to the extended design of the gas pipeline of the inner ring 22, the process gas at the junction 23 of the inner ring 22 and the outer ring 21 is less than that in other areas, which will make the metal film deposited corresponding to the junction 23 of the inner and outer rings thinner. In order to solve this problem, in this embodiment, the junction 23 between the inner ring 22 and the outer ring 21 is provided with a plurality of third air holes 231 extending in the height direction, and the third air holes 231 are connected to the top surface of the junction 23 and the bottom surface of the junction 23. The third air holes 231 can be evenly arranged in a circle along the circumference of the junction 23. The aperture of the first air hole 211 is the same as the aperture of the second air hole, and the aperture of the third air hole 231 is larger than the aperture of the first air hole 211 and the aperture of the second air hole 221. The aperture of the third pore 231 is 2 to 4 times the aperture of the first pore 211, and can be 3 times, but the present application is not limited thereto. For example, the apertures of the first pore 211 and the second pore 221 can be set to about 1 mm, while the aperture of the third pore 231 is set to about 3 mm, so that more process gas passes through the gas channel of the third pore 231 at the junction 23, compensating for the deposition thickness at the junction 23.

[0041] Furthermore, if Figure 5 As shown, in this embodiment, a slope 232 is provided on the bottom surface of the junction 23 corresponding to the position of the third air hole 231, and the slope 232 is inclined upward from the inside to the outside. Figure 5 The arrow in the middle shows the flow direction of the gas. By setting the slope 232, the gas is forced to change its flow direction, and the process gas at the junction 23 is supplemented, which is beneficial to the deposition of the metal film, so that the film deposition at the junction 23 of the inner and outer circles is improved, thereby further improving the uniformity of the metal film as a whole. The slope 232 can also play a role in smooth transition between the inner circle 22 and the outer circle 21.

[0042] In summary, the present application provides a gas shower head structure for improving the uniformity of deposited thin films by adjusting the gas flow rate and a deposition device including the gas shower head. One or more gas shower heads in the deposition device can adopt the gas shower head structure in which the inner ring 22 is higher than the outer ring 21. Specifically, which gas shower heads adopt this design can be selected according to needs. The present application reduces the film deposition rate corresponding to the inner ring 22 by designing the height of the inner ring 22 to be higher than the outer ring 21, reduces the influence of the edge minimum coverage ring, can change the deposition film thickness at the edge of the wafer, improves the uniformity of the film, and in some embodiments, can further optimize the aperture of the third air hole 231 at the junction 23 of the inner ring 22 and the outer ring 21 to allow more process gas to pass through, and set a slope 232 below the third air hole 231 to change the gas flow direction, supplement the process gas at the junction 23, and improve the uniformity of the film as a whole. The present application is beneficial to optimizing the electrical properties of the contact holes of the outer ring 21, improving the yield of the product, promoting the efficiency of production, and greatly ensuring the reliability of the product.

[0043] The above content is a further detailed description of the present application in combination with specific preferred implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be deemed to fall within the scope of protection of the present application.

Claims

1. A gas shower head, characterized in that: For a deposition device, the gas shower head comprises: An outer ring, wherein a plurality of first air holes extending in a height direction are distributed inside the outer ring, and the first air holes communicate with a top surface of the outer ring and a bottom surface of the outer ring; The inner ring is arranged inside the outer ring, and a plurality of second air holes extending in the height direction are distributed inside the inner ring, and the second air holes connect the top surface of the inner ring and the bottom surface of the inner ring. The height of the inner ring is greater than the height of the outer ring, so that the bottom surface of the inner ring protrudes downward relative to the outer ring.

2. The gas shower head according to claim 1, characterized in that: The length of the airway in the second pore is 1.2 to 1.8 times the length of the airway in the first pore.

3. The gas shower head according to claim 1, characterized in that: A plurality of third air holes extending in the height direction are provided at the junction between the inner ring and the outer ring, and the third air holes communicate with the top surface of the junction and the bottom surface of the junction.

4. The gas shower head according to claim 3, characterized in that: The third air holes are evenly arranged in a circle along the circumference of the junction.

5. The gas shower head according to claim 3, characterized in that: The aperture of the third pore is larger than the aperture of the first pore and the aperture of the second pore.

6. The gas shower head according to claim 5, characterized in that: The aperture of the first pore is the same as the aperture of the second pore, and the aperture of the third pore is 2 to 4 times the aperture of the first pore.

7. The gas shower head according to claim 3, characterized in that: A bottom surface of the junction corresponding to the position of the third air hole is provided with a slope, and the slope is inclined upward from the inside to the outside.

8. The gas shower head according to claim 1, characterized in that: The first air holes and the second air holes are arranged in a plurality of concentric circles.

9. The gas shower head according to claim 1, characterized in that: The top surface of the inner ring is flush with the top surface of the outer ring.

10. A deposition device, characterized in that: The invention comprises a plurality of gas shower heads, wherein at least one of the gas shower heads adopts the structure of the gas shower head according to any one of claims 1 to 9.

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