Stop piece structure of pressure control valve arranged above molecular pump in process cavity

Abstract

The invention provides a separation blade structure of a pressure control valve arranged above a molecular pump in a process cavity, the separation blade structure comprises a sliding rod mechanism and a baffle, the sliding rod mechanism comprises a sliding rod and a sliding block, and the sliding block can move along the sliding rod; the baffle comprises a plurality of separation blades, the separation blades are connected with the sliding block through fixed connection points, each separation blade comprises a separation blade groove penetrating through the upper surface and the lower surface, and the separation blades penetrate through the sliding rod through the separation blade grooves and are tightly arranged into a circle with the position where the sliding rod is located as the circle center; when the sliding block moves along the sliding rod, all the blocking pieces move in the transverse direction. According to the invention, the problem that the uniformity of the key size in the wafer surface becomes poor due to the asymmetry of the opening and closing mode of the baffle plate in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor manufacturing, and in particular to a baffle structure of a pressure control valve arranged above a molecular pump in a process chamber. Background Art

[0002] In the field of semiconductor manufacturing technology, when etching, chemical vapor deposition and other process machines process wafers, the working pressure is about 2mtorr~1torr. The principle of controlling the operating pressure of the process chamber is: when a certain volume of gas flows into the chamber, the pressure gauge feedback controls the opening size of the upper baffle of the molecular pump to stabilize the process pressure.

[0003] Different types of baffles have different opening and closing methods. For example, the widely used pendulum valve has a disc as its active structure. The disc moves left and right to control the size of the opening, thereby controlling the pressure in the cavity. However, the opening and closing method of the pendulum valve is asymmetric (such as Figure 1 As shown in the figure, the pumping rates on both sides of the chamber are different. In this case, the distribution of plasma will be uneven, which will eventually lead to poor uniformity of the critical dimensions within the wafer surface and obvious special distribution. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a baffle structure of a pressure control valve arranged above a molecular pump in a process chamber, so as to solve the problem that the uniformity of key dimensions within the wafer surface deteriorates due to the asymmetry of the opening and closing method of the baffle.

[0005] To achieve the above-mentioned purpose and other related purposes, the present invention provides a baffle structure of a pressure control valve disposed above a molecular pump in a process chamber, the structure comprising: a slide rod mechanism and a baffle plate,

[0006] The slide bar mechanism includes a slide bar and a slider, and the slider can move up and down along the slide bar;

[0007] The baffle plate includes a plurality of baffles, and the plurality of baffles are connected to the slider through a fixed connection point, and each of the baffles includes a baffle groove penetrating the upper and lower surfaces, and each of the baffles is passed through the baffle groove on the slider, and is closely arranged in a circle with the slider as the center;

[0008] When the slider moves along the slide rod, each baffle moves in a transverse direction, and the length of the baffle groove determines the opening and closing range of the valve.

[0009] Optionally, the length of the baffle groove is 6 cm to 10 cm.

[0010] Optionally, the length of the baffle is between 12 cm and 20 cm.

[0011] Optionally, the blocking plate groove is rectangular in a top view.

[0012] Optionally, the baffle is fan-shaped, and the fixed connection point is located on a side of the baffle groove close to the arc edge.

[0013] Optionally, the number of the baffles ranges from 12 to 36.

[0014] Optionally, when viewed from a top view, there is no space between the edges of adjacent baffles.

[0015] Optionally, the sliding rod is an elongated round rod.

[0016] Optionally, the slide bar mechanism further comprises a guide rail and a transmission part, wherein the guide rail is used to ensure smooth movement of the slider on the slide bar, and the transmission part is used to transmit power from a power source to the slider.

[0017] Optionally, the slider has a plurality of slider connection points, and each of the slider connection points is respectively connected to the fixed connection point on each of the baffles through a long strip structure.

[0018] Optionally, when the slider moves downward along the slide rod, the long strip structure pushes each of the baffles to move in a direction away from the slide rod; when the slider moves upward along the slide rod, the long strip structure pulls each of the baffles to move in a direction close to the slide rod.

[0019] As described above, the baffle structure of the pressure control valve disposed above the molecular pump in the process chamber of the present invention controls the opening of the pressure control valve in a "concentric circle" scaling form with the baffle on the upper part of the molecular pump, thereby improving the symmetry of the process chamber, ensuring that the pumping rate in all directions of the wafer is more uniform, and maintaining better uniformity of the plasma in the chamber, which greatly improves the uniformity of key dimensions within the wafer surface and improves the wafer uniformity. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The diagram shows an asymmetric opening of the baffle structure of a conventional pendulum valve.

[0021] Figure 2 A schematic top view of a baffle according to the present invention is shown.

[0022] Figure 3 Shown is a schematic front view of a baffle according to the present invention.

[0023] Figure 4 Shown is a schematic side view of a single baffle of the present invention. DETAILED DESCRIPTION

[0024] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0025] See also Figures 1 to 4 It should be noted that the illustrations provided in this embodiment are only schematic illustrations of the basic concept of the present invention. Although the illustrations only show components related to the present invention and are not drawn according to the number, shape and size of components in actual implementation, the form, quantity and proportion of each component in actual implementation may be changed arbitrarily, and the component layout may also be more complicated.

[0026] like Figure 2 to Figure 4 As shown, this embodiment provides a baffle structure of a pressure control valve disposed above a molecular pump in a process chamber, the structure comprising a slide rod mechanism and a baffle.

[0027] The slide bar mechanism includes a slide bar and a slider, and the slider can move up and down along the slide bar;

[0028] The baffle plate includes a plurality of baffles, and the plurality of baffles are connected to the slider through a fixed connection point, and each of the baffles includes a baffle groove penetrating the upper and lower surfaces, and each of the baffles is passed through the baffle groove on the slider, and is closely arranged in a circle with the slider as the center;

[0029] When the slider moves along the slide rod, each baffle moves in a transverse direction, and the length of the baffle groove determines the opening and closing range of the valve.

[0030] In this embodiment, the longitudinal movement of the slide bar mechanism is converted into the lateral movement of the plurality of baffles, thereby realizing the "concentric circle zooming" form. Moreover, in this embodiment, the length of the baffle groove (that is, the moving range of the baffle) represents the opening and closing range of the pressure control valve.

[0031] Specifically, the sliding rod is a long round rod.

[0032] Specifically, the slide bar mechanism further includes a guide rail and a transmission part, wherein the guide rail is used to ensure the smooth movement of the slider on the slide bar, and the transmission part is used to transmit power from a power source to the slider.

[0033] In this embodiment, the guide rails and the transmission parts are not shown in the figures.

[0034] Specifically, the slider has a plurality of slider connection points, and each of the slider connection points is respectively connected to the fixed connection point on each of the baffles through a long strip structure.

[0035] More specifically, when the slider moves downward along the slide rod, the long strip structure pushes each of the baffles to move in a direction away from the slide rod; when the slider moves upward along the slide rod, the long strip structure pulls each of the baffles to move in a direction close to the slide rod.

[0036] In this embodiment, when the slider moves downward, the strip structure pushes the baffle to move away from the slide rod under the action of force, and when the slider moves upward, the strip structure pulls the baffle to move toward the slide rod under the action of force.

[0037] Specifically, the length of the baffle groove is 6 cm to 10 cm.

[0038] Specifically, the blocking plate groove is rectangular in a top view.

[0039] Specifically, the number of the baffles ranges from 12 to 36.

[0040] Specifically, the length of the baffle is between 12 cm and 20 cm.

[0041] Specifically, the baffle is fan-shaped, and the fixed connection point is located on a side of the baffle groove close to the arc-shaped edge.

[0042] Specifically, from a top view, there is no space between the edges of adjacent baffles.

[0043] In summary, the baffle structure of the pressure control valve disposed above the molecular pump in the process chamber of the present invention controls the opening of the pressure control valve in a "concentric circle" scaling form by using the baffle on the upper part of the molecular pump, thereby improving the symmetry of the process chamber, ensuring that the pumping rate in all directions of the wafer is more uniform, and maintaining better uniformity of the plasma in the chamber, which greatly improves the uniformity of the key dimensions within the wafer surface and improves the uniformity of the wafer. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

[0044] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A baffle structure of a pressure control valve disposed above a molecular pump in a process chamber, characterized in that: The structure comprises: a slide bar mechanism and a baffle, The slide bar mechanism includes a slide bar and a slider, and the slider can move up and down along the slide bar; The baffle plate includes a plurality of baffles, and the plurality of baffles are connected to the slider through a fixed connection point, and each of the baffles includes a baffle groove penetrating the upper and lower surfaces, and each of the baffles is passed through the baffle groove on the slider, and is closely arranged in a circle with the slider as the center; When the slider moves along the slide rod, each baffle moves in a transverse direction, and the length of the baffle groove determines the opening and closing range of the valve.

2. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1, characterized in that: The length of the baffle groove is 6 cm to 10 cm.

3. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1 or 2, characterized in that: The length of the baffle is between 12 cm and 20 cm.

4. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 3, characterized in that: The top view of the baffle groove is rectangular.

5. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1, characterized in that: The baffle is fan-shaped, and the fixed connection point is located on a side of the baffle groove close to the arc edge.

6. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1, characterized in that: The number of the baffles ranges from 12 to 36.

7. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1, characterized in that: Seen from a top view, there is no space between the edges of adjacent baffles.

8. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1, characterized in that: The sliding rod is a long round rod.

9. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1, characterized in that: The slide bar mechanism further comprises a guide rail and a transmission part, wherein the guide rail is used to ensure the smooth movement of the slide block on the slide bar, and the transmission part is used to transmit power from a power source to the slide block.

10. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 1, characterized in that: The slider has a plurality of slider connection points, and each of the slider connection points is respectively connected to the fixed connection point on each of the baffles through a long strip structure.

11. The baffle structure of the pressure control valve disposed above the molecular pump in the process chamber according to claim 10, characterized in that: When the slider moves downward along the slide bar, the long strip structure pushes each of the baffles to move in a direction away from the slide bar; when the slider moves upward along the slide bar, the long strip structure pulls each of the baffles to move in a direction close to the slide bar.

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