Pressure control device of semiconductor cavity

Abstract

A pressure control device of a semiconductor cavity comprises the components of a cavity of which the bottom is provided with a plurality of openings which are arranged along the circumferential direction; and the pendulum valves correspond to the openings in a one-to-one mode, the pendulum valves are arranged at the positions of the openings respectively, and the pendulum valves are used for adjusting the opening degrees of the openings. The pressure control device of the semiconductor cavity provided by the embodiment of the utility model is beneficial to improving the uniformity of the pumping speed when the gas in the cavity is pumped out, and improving the gas pressure in the cavity, thereby improving the uniformity of a semiconductor process.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing technology, and in particular to a pressure control device for a semiconductor cavity. Background Technology

[0002] In vacuum processes of semiconductor manufacturing, such as etching, the stability of pressure within the reaction chamber is crucial for the uniformity and stability of the process. In practice, a pendulum valve is typically used to control the pressure stability within the reaction chamber. Generally, the reaction chamber has an extraction port, and an extraction system is installed corresponding to this port to remove excess gas from the reaction chamber. The pendulum valve is located at this extraction port, and by adjusting the opening of the pendulum valve, the pressure within the reaction chamber is controlled.

[0003] However, when the pendulum valve controls the opening of the exhaust port, since the valve plate opens the exhaust port from one side, there will be a certain angle, which will inevitably deviate to one side. The travel of the gas on the left and right sides of the reaction chamber is inconsistent, which makes it impossible for the gas on the left and right sides of the reaction chamber to be extracted evenly. The gas pressure in the reaction chamber is uneven, which in turn affects the uniformity of the semiconductor process and the stability of the environment in the reaction chamber.

[0004] Therefore, there is an urgent need to provide a pressure control device for a semiconductor cavity to ensure uniform gas pumping speed within the reaction chamber, thereby improving the uniformity of the process. Utility Model Content

[0005] The technical problem solved by this utility model is to provide a pressure control device for a semiconductor cavity, which controls the gas flow rate in the semiconductor cavity to be uniform, thereby improving the stability of the environment in the cavity and the uniformity of the semiconductor process.

[0006] To solve the above-mentioned technical problems, this utility model provides a pressure control device for a semiconductor cavity, comprising: a cavity, wherein a plurality of circumferentially arranged openings are provided on the bottom of the cavity; a plurality of pendulum valves, wherein each pendulum valve corresponds to one of the openings, and the plurality of pendulum valves are respectively disposed at each of the openings, wherein the pendulum valves are used to adjust the opening degree of the openings.

[0007] Optionally, when there are two openings, the two openings are arranged in a centrally symmetrical manner with respect to the center point of the bottom.

[0008] Optionally, when the number of openings is greater than two, the multiple openings are arranged circumferentially at equal intervals on the bottom of the cavity.

[0009] Optionally, the opening is circular in shape, and the areas of the multiple openings are equal. When the number of openings is greater than two, the center distance between each adjacent opening is equal.

[0010] Optionally, the pendulum valve includes: an air inlet and an air outlet, the shapes of which are adapted to the shape of the opening, and the airflow channel formed by the air inlet and the air outlet being aligned with the opening; and a valve plate perpendicular to the airflow channel, the valve plate being rotated to adjust the opening of the airflow channel.

[0011] Optionally, the valve plate can be rotated away from the center point of the bottom to increase the opening of the airflow channel until the airflow channel is fully opened, and the valve plate can be rotated towards the center point of the bottom to decrease the opening of the airflow channel until the airflow channel is completely closed.

[0012] Optionally, each of the valve plates controls the opening degree of the airflow channel to be equal.

[0013] Optionally, the pendulum valve further includes a drive mechanism for driving the valve plate to rotate.

[0014] Optionally, it also includes a vacuum pump connected to the opening, the vacuum pump being used to extract gas from the cavity.

[0015] Optionally, the cavity is a wafer etching cavity.

[0016] Compared with the prior art, the technical solution of this utility model embodiment has the following beneficial effects:

[0017] The pressure control device for the semiconductor cavity provided by this technical solution has multiple circumferentially arranged openings at the bottom of the cavity, and a pendulum valve corresponding to each opening is also provided at the opening. Each pendulum valve controls the opening degree of each opening individually. With multiple openings arranged circumferentially along the bottom of the cavity, the gas in the cavity is extracted through multiple openings in a dispersed manner. Compared with the gas being extracted from a single side, this improves the uniformity of airflow distribution and the uniformity of gas pressure in the cavity, thereby helping to improve the stability of the process environment in the cavity and the uniformity of the semiconductor process. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a pressure control device for a semiconductor cavity in one embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram showing the distribution of multiple openings in one embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram showing the distribution of multiple openings in another embodiment of the present invention;

[0021] Figure 4 This is a simplified structural diagram of the pendulum valve in one embodiment of the present invention;

[0022] Figures 5 to 6 This is a schematic diagram illustrating the process of adjusting the opening degree of the pendulum valve in one embodiment of this utility model. Detailed Implementation

[0023] As described in the background section, pendulum valves are commonly used in semiconductor manufacturing processes to regulate and control the gas pressure within the semiconductor process chamber. Currently, a vent is typically located at the bottom of the semiconductor chamber, and a pendulum valve is installed at this vent to control the opening degree of the vent and thus regulate the gas pressure. Because the pendulum valve usually opens from one side of the vent, the gas being extracted from the chamber is also biased to one side, with a faster extraction rate on the open side and a slower extraction rate on the other side. This affects the uniformity of the semiconductor process within the chamber; for example, it can cause different etching rates on different sides during etching processes, impacting the performance of the resulting semiconductor device.

[0024] To address the aforementioned issues, this invention provides a pressure control device for a semiconductor cavity. Multiple openings are circumferentially arranged at the bottom of the cavity, along with multiple pendulum valves, each corresponding to one of the openings. Each pendulum valve controls one opening. Gas within the cavity is dispersed and extracted through these multiple openings. Compared to extraction from a single side, extraction from multiple directions results in a more uniform gas flow, improving the uniformity of airflow distribution and gas extraction speed within the cavity. This, in turn, enhances the uniformity of the semiconductor process and improves the performance of the resulting semiconductor structure.

[0025] To make the above-mentioned objectives, features and beneficial effects of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0026] Figure 1 This is a schematic diagram of the structure of a pressure control device for a semiconductor cavity in one embodiment of the present invention; Figure 2 This is a schematic diagram of the opening distribution at the bottom of the cavity in one embodiment of the present invention; Figure 3 This is a schematic diagram of the opening distribution at the bottom of the cavity in another embodiment of the present invention; Figure 4 This is a simplified structural diagram of the pendulum valve in one embodiment of the present invention; Figures 5 to 6 This is a schematic diagram illustrating the process of adjusting the opening degree of the pendulum valve in one embodiment of this utility model.

[0027] Reference Figures 1 to 3 The pressure control device for the semiconductor cavity includes: a cavity 10, on the bottom 11 of the cavity 10, a plurality of circumferentially arranged openings 20; a plurality of pendulum valves 30, each of the pendulum valves 30 corresponding to one of the openings 20, and the plurality of pendulum valves 30 being respectively disposed at each of the openings 20, the pendulum valves 30 being used to adjust the opening degree of the opening 20.

[0028] In this embodiment, the cavity 10 is a wafer etching cavity; in other embodiments, the cavity may also be other process cavities that require control of gas pressure.

[0029] In this embodiment, the pressure control device of the semiconductor cavity further includes a vacuum pump 12, which is connected to a plurality of openings 20 and is used to extract gas from the cavity 11.

[0030] In this embodiment, the air pump 12 is connected to the opening 20 via the pendulum valve 30.

[0031] In this embodiment, the vacuum pump 12 is a molecular pump.

[0032] In this embodiment, the number of pendulum valves 30 is the same as the number of openings 20. A pendulum valve 30 is provided at each opening 20, and each pendulum valve 30 controls the opening degree of an opening 20 independently.

[0033] In this embodiment, by providing multiple openings 20 along the circumference on the bottom 11, and each opening 20 being individually controlled by a pendulum valve 30, the gas inside the cavity 10 can be extracted through multiple openings 20, reducing the non-uniformity of airflow inside the cavity caused by extraction from a single opening, and improving the uniformity of airflow distribution inside the cavity, thereby improving the uniformity of semiconductor process.

[0034] In this embodiment, the bottom 11 of the cavity 10 is circular, and the openings 20 are all circular in shape, with multiple openings 20 distributed along the circumference of the bottom 11.

[0035] In other embodiments, the bottom 11 of the cavity 10 can be a square or other polygon, and multiple openings 20 are distributed along the circumference of the polygon, which can also achieve the effect of balancing the air flow.

[0036] In some embodiments, the number of openings 20 may be two or more.

[0037] refer to Figure 2 In one embodiment, there are two openings 20, and the two openings 20 are arranged in a centrally symmetrical manner with respect to the center point A of the bottom 11.

[0038] In this embodiment, the two openings 20 are centrally symmetrically arranged on the bottom 11. When the gas in the cavity 10 is drawn out from the two openings 20, the gas travels symmetrically, thereby improving the uniformity of gas extraction and increasing the gas pressure in the cavity 10.

[0039] In other embodiments, the two openings 20 may not be centrally symmetrically arranged. However, when there are two openings 20, the two openings 20 cannot be located on the same side. Specifically, the bottom 11 is divided into a first region 110 and a second region 120 with the center line passing through the center point A of the bottom 11 as the boundary. The two openings 20 are located in the first region 110 and the second region 120 respectively. They cannot be located in the first region 110 or the second region 120 at the same time, so as to avoid the gas in the cavity 10 being extracted from one side of the cavity 10 alone.

[0040] In another embodiment, the number of openings 20 may be greater than two, with the plurality of openings 20 arranged circumferentially at equal intervals along the bottom 11 of the cavity 10. Specifically, refer to Figure 3 In this embodiment, four openings 20 are provided on the bottom 11, and the distance between any two adjacent openings 20 is equal.

[0041] In this embodiment, the opening 20 is circular in shape, and the equal spacing between multiple openings 20 can be understood as the center distance between each adjacent opening 20 being equal.

[0042] In other embodiments, when the shape of the opening 20 is a quadrilateral or other shape, the equal spacing between the multiple openings 20 can be understood as the distance between the center points of each adjacent opening 20 being equal.

[0043] In other embodiments, the multiple openings 20 may also be spaced unequally. Similarly, the bottom 11 is divided into a first region 110 and a second region 120 with the center line passing through the center point A of the bottom 11 as the boundary. The difference between the number of openings in the first region 110 and the number of openings in the second region 120 is less than or equal to 1. Preferably, the total area of ​​the openings in the first region 110 and the total area of ​​the openings in the second region 120 are equal, which can improve the uniformity of gas extraction in the cavity 10.

[0044] In this embodiment, the areas of the plurality of openings 20 are equal. Having equal areas of the plurality of openings 20 makes it easier to control the opening degree of the openings 20 to be equal, thereby controlling the flow rate of gas extracted from each opening 20 to be equal.

[0045] refer to Figure 4 The pendulum valve 30 includes: an air inlet 31 and an air outlet 32, the shapes of the air inlet 31 and the air outlet 32 ​​being adapted to the shape of the opening 20, and the airflow channel 33 formed by the air inlet 31 and the air outlet 32 ​​being aligned with the opening 20; and a valve plate 34, the valve plate 34 being perpendicular to the airflow channel 33, and the valve plate 34 being rotated to adjust the opening of the airflow channel 33.

[0046] The pendulum valve 30 includes a valve cover 35, with an air inlet 31 and an air outlet 32 ​​disposed on the valve cover 35, and a valve plate 34 disposed inside the valve cover 35.

[0047] In this embodiment, the airflow channel 33 is aligned with the opening 20, and the valve plate 34 adjusts the opening of the airflow channel 33 in a manner equivalent to adjusting the opening of the opening 20.

[0048] In this embodiment, the pendulum valve 30 further includes a drive mechanism 36, which is used to drive the valve plate 34 to rotate.

[0049] In this embodiment, the drive mechanism 36 is a motor.

[0050] In this embodiment, the driving mechanism 36 drives the valve plate 34 to rotate. By controlling the rotation angle of the valve plate 34, the overlap between the valve plate 34 and the airflow channel 33 is controlled, that is, the opening of the airflow channel 33 is controlled. Since the airflow channel 33 is aligned with the opening 20, the opening of the opening 20 can be controlled.

[0051] refer to Figures 5 to 6 In this embodiment, the valve plate 34 rotates away from the center point A of the bottom 11 to increase the opening of the airflow channel 33 until the airflow channel 33 is fully opened, and the valve plate 34 rotates towards the center point A of the bottom 11 to decrease the opening of the airflow channel 33 until the airflow channel 33 is completely closed.

[0052] In this embodiment, each valve plate 34 rotates in a direction away from the center point A of the bottom 11. After reaching the position where the center point of the valve plate 34 is furthest from the center point A of the bottom 11, it rotates again in a direction closer to the center point A of the bottom 11. When the center point of the valve plate 34 is closest to the center point A of the bottom 11, the valve plate 34 completely closes the airflow channel 33, that is, completely closes the opening 20; when the center point of the valve plate 34 is furthest from the center point A of the bottom 11, the valve plate 34 completely opens the airflow channel 33, that is, completely opens the opening 20.

[0053] By controlling the valve plate 34 to move away from the center point A of the bottom 11 at the same time, or to move closer to the center point A of the bottom 11 at the same time, the opening of the formed opening 20 can be made basically symmetrical, thereby controlling the uniformity of gas extraction and the uniformity of gas distribution in the cavity 10.

[0054] In this embodiment, each valve plate 34 controls the opening degree of the airflow channel 33 to be equal, that is, each valve plate 34 controls the opening degree of the opening 20 to be equal, thereby ensuring that the airflow drawn out from each opening 20 has a consistent speed.

[0055] In this embodiment, multiple openings 20 are provided, and each opening 20 is individually controlled by a pendulum valve 30. Therefore, the pendulum valve 30 can be a small-diameter valve, which has stronger control precision and faster response speed.

[0056] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A pressure control device for a semiconductor cavity, characterized in that, include: A cavity, wherein a plurality of circumferentially arranged openings are provided on the bottom of the cavity; Multiple pendulum valves are provided, each corresponding to one of the openings. The multiple pendulum valves are respectively installed at each of the openings, and the pendulum valves are used to adjust the opening degree of the opening.

2. The pressure control device for a semiconductor cavity as described in claim 1, characterized in that, When there are two openings, the two openings are arranged in a centrally symmetrical manner with respect to the center point of the bottom.

3. The pressure control device for a semiconductor cavity as described in claim 1, characterized in that, When the number of openings is greater than two, the multiple openings are arranged circumferentially at equal intervals on the bottom of the cavity.

4. The pressure control device for a semiconductor cavity as described in claim 2 or 3, characterized in that, The opening is circular in shape, and the areas of multiple openings are equal. When the number of openings is greater than two, the center distance between each adjacent opening is equal.

5. The pressure control device for a semiconductor cavity as described in claim 1, characterized in that, The pendulum valve includes: an air inlet and an air outlet, the shapes of which are adapted to the shape of the opening, and the airflow channel formed by the air inlet and the air outlet being aligned with the opening; and a valve plate perpendicular to the airflow channel, the valve plate being adjusted by rotating to regulate the opening of the airflow channel.

6. The pressure control device for a semiconductor cavity as described in claim 5, characterized in that, The valve plate rotates away from the center point of the bottom to increase the opening of the airflow channel until the airflow channel is fully opened, and rotates towards the center point of the bottom to decrease the opening of the airflow channel until the airflow channel is completely closed.

7. The pressure control device for a semiconductor cavity as described in claim 6, characterized in that, Each of the valve plates controls the opening degree of the airflow channel to be equal.

8. The pressure control device for a semiconductor cavity as described in claim 5, characterized in that, The pendulum valve also includes a drive mechanism for driving the valve plate to rotate.

9. The pressure control device for a semiconductor cavity as described in claim 1, characterized in that, It also includes a vacuum pump connected to the opening, which is used to extract gas from the cavity.

10. The pressure control device for a semiconductor cavity as described in claim 1, characterized in that, The cavity is a wafer etching cavity.

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