Air exhaust assembly and process chamber

Abstract

The utility model provides an air exhaust assembly and a process chamber, the air exhaust assembly comprises an annular lining structure and a baffle structure which are arranged in a cavity, the lining structure is arranged around a base, and an air exhaust channel is formed between the lining structure and the cavity wall of the cavity; a plurality of first air exhaust holes and a plurality of second air exhaust holes are formed in the side wall of the lining structure; when the base is located at the process position, the plurality of first exhaust holes are located above the bearing surface of the base; the baffle structure is arranged around the side wall of the lining structure and can ascend and descend relative to the lining structure, and the baffle structure can shield the multiple first air exhaust holes or the multiple second air exhaust holes. The baffle structure shields the second air exhaust hole, and the gaseous by-product can be discharged out of the cavity through the first air exhaust hole, the air exhaust channel and the air exhaust opening in sequence, so that the possibility that the gaseous by-product is in contact with the base in the process of discharging the gaseous by-product out of the cavity is greatly reduced, and the gaseous by-product is prevented from forming a solid by-product on the base when encountering cold; therefore, the good cleanliness in the cavity is ensured, and the product yield is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductors, and in particular to an exhaust component and a process chamber. Background Art

[0002] In the manufacturing process of integrated circuit chips, in order to meet the requirements of miniaturization of integrated circuit chip size and high requirements for morphology control, multiple patterns are usually etched on silicon wafers. However, the surface of silicon wafers is easily naturally oxidized to form silicon oxide (SiO2), which causes silicon oxide to easily react with etching gas to form solid byproducts during dry etching process.

[0003] In order to remove solid by-products, after the etching process, the silicon wafer is usually controlled to move up relative to the base to the gas guide plate set at the top of the process chamber. The temperature of the gas guide plate is relatively high, which causes the silicon wafer to heat up, and the solid by-products are volatilized by heat to obtain gaseous by-products, which are then extracted from the process chamber. However, after cleaning the silicon wafer in this way, solid by-products are easily attached to the base, and the solid by-products attached to the base may crack or fall off during the subsequent process, affecting the product yield. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art, and proposes an exhaust component and a process chamber.

[0005] In a first aspect, the utility model provides an exhaust assembly, which is applied to a process chamber, the process chamber comprising a cavity and a base located in the cavity, the exhaust assembly comprising an annular lining structure and an annular baffle structure; the lining structure is used to be arranged in the cavity and surround the base to enclose a process area, and the lining structure is also used to form an exhaust channel with the cavity wall of the cavity;

[0006] The side wall of the lining structure has multiple first exhaust holes and multiple second exhaust holes; the process area is connected to the exhaust channel through the multiple first exhaust holes and / or multiple second exhaust holes; wherein, when the base is located in the process position, the multiple first exhaust holes are located above the base bearing surface, and the multiple second exhaust holes are located below the base bearing surface; the baffle structure is arranged around the side wall of the lining structure, and can be raised and lowered relative to the lining structure, and the baffle structure is used to selectively block the multiple first exhaust holes or the multiple second exhaust holes.

[0007] In an implementation of the first aspect of the utility model, the baffle structure includes a first blocking ring, a second blocking ring and a connecting rod, the first blocking ring is located above the second blocking ring, and the connecting rod is fixedly connected to the first blocking ring and the second blocking ring; the baffle structure can move between a first position and a second position; when the baffle structure is located at the first position, the first blocking ring blocks the multiple first air extraction holes, and the multiple second air extraction holes are exposed; when the baffle structure is located at the second position, the second blocking ring blocks the multiple second air extraction holes, and the multiple first air extraction holes are exposed.

[0008] In an implementation of the first aspect of the utility model, at least one circle of first air extraction holes and at least one circle of second air extraction holes are provided on the side wall of the lining structure, and the first air extraction holes in each circle are arranged at intervals along the circumference of the lining structure, and the second air extraction holes in each circle are arranged at intervals along the circumference of the lining structure.

[0009] In an implementation of the first aspect of the utility model, the first air exhaust hole is provided with a circle, the first air exhaust hole is a circular hole and its diameter is greater than or equal to 3mm and less than or equal to 4mm, and the height of the first blocking ring along the vertical direction is greater than or equal to 5mm; and / or, the second air exhaust hole is provided with a circle, the second air exhaust hole is a circular hole and its diameter is greater than or equal to 3mm and less than or equal to 4mm, and the height of the second blocking ring along the vertical direction is greater than or equal to 5mm.

[0010] In an implementation of the first aspect of the present invention, the lining structure includes a first annular plate, a first annular liner, and a second annular plate that are coaxially arranged, and the first annular plate, the first annular liner, and the second annular plate are stacked in sequence from top to bottom;

[0011] Multiple first air extraction holes and multiple second air extraction holes are all arranged on the first annular liner; the baffle structure is located between the first annular plate and the second annular plate, the first annular plate is used to limit the vertical upward displacement of the baffle structure, and the second annular plate is used to limit the vertical downward displacement of the baffle structure.

[0012] In an implementation of the first aspect of the present invention, the liner structure further includes a third annular plate and a second annular liner coaxially arranged with the first annular liner, the second annular plate is superimposed on the second annular liner, and the second annular liner is superimposed on the third annular plate;

[0013] The first annular plate, the first annular liner and the second annular plate are used to enclose a first flow space together with the cavity wall, and the second annular plate, the second annular liner and the third annular plate are used to enclose a second flow space together with the cavity wall. A notch is provided on the second annular plate, and the first flow space is connected to the second flow space through the notch to form an exhaust channel.

[0014] In an implementation of the first aspect of the utility model, the second annular lining includes an arc-shaped plate, a first stop plate, and a second stop plate, one end of the arc-shaped plate is connected to the first end of the first stop plate, and the other end is connected to the first end of the second stop plate; the first stop plate and the first end to the second end of the second stop plate extend from the inner circumferential surface of the second annular plate to the outer circumferential surface of the second annular plate; a film transmission port is formed between the second end of the first stop plate and the second end of the second stop plate, the film transmission port is connected to the process area, and the film transmission port is used for silicon wafers to pass through; and the notch is arranged in the area of ​​the second annular plate corresponding to the arc-shaped plate.

[0015] In an implementation of the first aspect of the utility model, the first annular plate and the first annular liner are fixedly connected to form an integral structure, and the second annular plate, the second annular liner and the third annular plate are fixedly connected to form an integral structure.

[0016] In an implementation of the first aspect of the utility model, the baffle structure and the side wall gap of the lining structure are matched, and the gap between the baffle structure and the side wall of the lining structure along the radial direction of the lining structure is greater than or equal to 0.1 mm and less than or equal to 0.2 mm.

[0017] In the second aspect, the utility model provides a process chamber, comprising: a cavity and a base arranged in the cavity and any one of the vacuum components provided by the first aspect of the utility model, a vacuum port is provided on the cavity wall of the cavity, and the vacuum port is used to connect to the vacuum pump; the lining structure is arranged around the cavity wall and the base and forms a vacuum channel with the cavity wall, and the vacuum channel is connected to the vacuum port; the base can be raised and lowered, and the base can rise from below the multiple second vacuum holes to the process position.

[0018] The utility model has the following beneficial effects:

[0019] The vacuum assembly provided by the utility model is provided with a plurality of first vacuum holes and a plurality of second vacuum holes by designing an inner lining structure and a baffle structure. When the base is located at the process position, the first vacuum holes are located above the bearing surface, and the second vacuum holes are located below the bearing surface. In addition, the baffle structure can selectively block the plurality of first vacuum holes or the plurality of second vacuum holes. After the etching process, the baffle structure can block the plurality of second vacuum holes, so that the gaseous byproducts flow from the first vacuum holes into the vacuum channel, and then are discharged from the vacuum port to the outside of the cavity.

[0020] In this way, the possibility of gaseous by-products contacting the base during discharge out of the cavity is greatly reduced, which helps to avoid the gaseous by-products from forming solid by-products on the base due to cooling, thereby ensuring good cleanliness in the cavity and guaranteeing product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1( a ) and FIG. 1( b ) are schematic diagrams of a process chamber in the related art during an etching process and a cleaning process, respectively;

[0022] Figure 2 It is a structural schematic diagram of a lining structure in a process chamber in the related art;

[0023] Figure 3 for Figure 2 An exploded schematic diagram of the liner structure in the process chamber shown;

[0024] FIG. 4( a ) and FIG. 4( b ) are schematic diagrams showing the principles of a process chamber during an etching process and a cleaning process, respectively, provided in an embodiment of the present application;

[0025] Figure 5 A three-dimensional schematic diagram of an air extraction assembly provided in an embodiment of the present application when the baffle structure is located in a first position;

[0026] Figure 6 A three-dimensional schematic diagram of an air extraction assembly provided in an embodiment of the present application when the baffle structure is located in the second position;

[0027] Figure 7 A schematic diagram of an exploded view of an air extraction assembly provided in one embodiment of the present application.

[0028] Description of reference numerals:

[0029] 100-process chamber;

[0030] 10- cavity; 11- mixing chamber; 12- air inlet pipeline; 13- air extraction port;

[0031] 20- base;

[0032] 30- air guide plate;

[0033] 40-air extraction assembly;

[0034] 50- lining structure; 501- first air extraction hole; 502- second air extraction hole; 504- air extraction channel; 505- first circulation space; 506- second circulation space; 51- first annular lining; 52- first annular plate; 53- second annular plate; 531- notch; 54- third annular plate; 55- film transfer port;

[0035] 56 - second annular liner;

[0036] 60- baffle structure; 61- first blocking ring; 62- second blocking ring; 63- connecting rod;

[0037] 70-thimble;

[0038] 200-air pump;

[0039] 400-Silicon wafer. DETAILED DESCRIPTION

[0040] The following embodiments of the present application provide a process chamber, which can implement processes such as dry etching processes. Specifically, remote plasma assistance can be used to implement the dry etching process, or in-situ plasma assistance can be used to implement the dry etching process.

[0041] Taking remote plasma assisted dry etching as an example, the principle of the etching process is: an etching gas is introduced into the process chamber, the etching gas is NF3 and NH3, and the etching gas reacts with silicon oxide according to the following formula (1).

[0042] NF3+NH3+SiO2→(NH4)2SiF6+H2O Formula (I)

[0043] Of course, in some embodiments, pure gas-assisted dry etching can also be used. The principle of the etching process is: etching gas is introduced into the process chamber, the etching gas is HF and NH3, and the etching gas reacts with silicon oxide according to the following formula (II).

[0044] HF+NH3+SiO2→(NH4)2SiF6+H2O Formula (II)

[0045] According to formula (1) and formula (2), it can be understood that during the etching process, the silicon wafer is placed on a susceptor in the process chamber, the temperature of the susceptor is close to room temperature, and the etching gas combines with silicon oxide at room temperature to generate a solid by-product (NH4)2SiF6.

[0046] The principle of removing solid by-products is as follows: the silicon wafer is controlled to move relative to the base to a gas guide plate disposed on the top of the process chamber. The temperature of the gas guide plate is relatively high, so that the temperature of the silicon wafer rises. The solid by-products are decomposed by heat according to the following formula (III) to generate gaseous by-products SiF4, HF and NH3, and the gaseous by-products are extracted from the process chamber.

[0047] (NH4)2SiF6→SiF4+HF+NH3 Formula (III)

[0048] FIG. 1( a ) and FIG. 1( b ) are schematic diagrams showing a process chamber in the related art during an etching process and a cleaning process, respectively. Figure 2 A schematic diagram of a lining structure in a process chamber in the related art is shown. Figure 3 for Figure 2 The exploded schematic diagram of the lining structure shown in FIG. Figure 3In the example shown, a lining structure 50a is provided in the process chamber 100a of the related art. The lining structure 50a is arranged around the cavity wall of the cavity 10a and the base 20a. A circle of exhaust holes 501a is provided on the lining structure 50a. As shown in FIG. 1(a), during the etching process, the silicon wafer 400 is placed on the base 20a, and the exhaust hole 501a is located below the supporting surface of the base 20a; as shown in FIG. 1(b), during the cleaning process, the silicon wafer 400 is raised to be close to the air guide plate 30a with a higher temperature, and the solid by-products are decomposed into gaseous by-products by heat. The gaseous by-products flow from the exhaust hole 501a to between the lining structure 50a and the cavity wall of the cavity 10a, and then are discharged from the exhaust port 13a of the cavity 10a to the outside of the process chamber 100a under the suction action of the exhaust pump 200a. The flow path of the gaseous by-products is shown by the solid arrow in FIG. 1(b). The flow path of the gaseous by-products on the lining structure 50a is shown in FIG. Figure 2 Indicated by the solid arrow.

[0049] However, after the etching process is carried out in the process chamber 100a for a period of time, solid by-products are easily attached to the base 20a. The solid by-products attached to the base 20a may crack or fall off during the subsequent process, which may easily cause the particle size in the film layer on the silicon wafer 400 to exceed the standard, affecting the product yield. In addition, solid by-products are easily attached to the hole wall of the exhaust hole 501a, which affects the smoothness of the discharge of gaseous by-products. In order to avoid excessive accumulation of solid by-products on the base 20a and in the exhaust hole 501a of the lining structure 50a, the cavity 10a, the base 20a and the lining structure 50a need to be regularly maintained. Specifically, the cavity 10a is opened and the cavity wall of the cavity 10a is wiped to keep the cavity 10a clean, and the base 20a and the lining structure 50a are taken out for cleaning or replacement. During the maintenance process, the process chamber 100a needs to be shut down, which affects the production cycle of the product.

[0050] After careful analysis, the inventors of the present application found that the reason for the excessive accumulation of solid by-products on the base and in the exhaust holes of the lining structure is that: during the etching process, the temperature of the base is close to room temperature, and the temperature of the base is lower than the temperature of the air guide plate. The gaseous by-products are easily in contact with the base when flowing to the exhaust holes. When the gaseous by-products are cooled, they will be transformed back into solid (NH4)2SiF6 or ammonium fluoride NH4F, resulting in the generation of solid by-products on the base. In addition, in the vertical direction, the distance between the exhaust holes and the air guide plate on the lining structure is relatively far, and the temperature of the hole wall of the exhaust hole is low. When the gaseous by-products flow through the exhaust holes, they are cooled, resulting in the generation of solid by-products on the hole wall of the exhaust hole. The solid by-products will block part of the exhaust holes, resulting in a reduction in the amount of gaseous by-products allowed to pass through the exhaust holes per unit time.

[0051] Based on the above description, an embodiment of the present application provides a process chamber and an exhaust assembly thereof. In order to enable those skilled in the art to better understand the technical solution of the utility model, the exhaust assembly provided by the utility model and the process chamber equipped with the same are described in detail below in conjunction with the accompanying drawings.

[0052] FIG4(a) and FIG4(b) are schematic diagrams of the principles of a process chamber provided in an embodiment of the present application during an etching process and a cleaning process, respectively. The process chamber provided in an embodiment of the present application, as shown in FIG4(a) and FIG4(b), comprises a chamber 10 and a base 20, a side wall bottom of the chamber 10 is provided with an exhaust port 13, the exhaust port 13 is used to connect to an exhaust pump 200 arranged outside the chamber 10, the exhaust pump 200 is used to extract the gas in the chamber 10, the top of the chamber 10 also has a connected mixing chamber 11, the base 20 is located in the chamber 10, the base 20 has a bearing surface, and the bearing surface is used to bear a silicon wafer 400. The exhaust pump can be, for example, a dry pump or other types of vacuum pumps.

[0053] The process chamber 100 also includes an air inlet line 12, the inlet end of which is connected to a gas source (not shown) located outside the cavity 10, and the gas source is used to introduce etching gas into the cavity. The outlet end of the air inlet line 12 is connected to a mixing chamber 11, and the etching gas is mixed in the mixing chamber 11 to generate ammonium fluoride NH4F, and ammonium fluoride and silicon oxide can combine to generate a solid by-product (NH4)2SiF6.

[0054] An air guide plate 30 is also installed inside the cavity 10. The air guide plate 30 is located at the top of the cavity 10. The air guide plate 30 is provided with a plurality of spaced uniform flow holes. The etching gas mixed in the mixing chamber 11 flows into the cavity 10 through the uniform flow holes, thereby improving the uniformity of the etching gas.

[0055] It is understandable that the process chamber 100 of this embodiment may also include a first lifting device, which is arranged outside the cavity 10 and can drive the base 20 to rise and fall between the film transfer position and the process position in the vertical direction, and the film transfer position is below the process position.

[0056] The process chamber 100 also includes a second lifting device (not shown) and three ejector pins 70. Three vias are provided on the base 20. Any one of the three ejector pins 70 is correspondingly inserted into one via. The second lifting device can drive the ejector pin 70 to move up and down along the via. The ejector pin 70 lifts the silicon wafer 400 so that the silicon wafer 400 can move in the vertical direction. The ejector pin 70 can be lifted between a first height and a second height. At the first height, the silicon wafer 400 is placed on the bearing surface. At the second height, the silicon wafer 400 is located above the bearing surface and there is a certain distance between the two. It can be understood that the number of ejector pins 70 and vias is not limited to the above number, and can be specifically designed according to needs and actual working conditions.

[0057] The process chamber 100 further includes an exhaust assembly, which is disposed inside the cavity 10. The structure of the exhaust assembly provided in the embodiment of the present application is described in detail below in conjunction with the accompanying drawings.

[0058] Figure 5 This is a three-dimensional schematic diagram of an air extraction assembly provided in an embodiment of the present application when the baffle structure 60 is located in the first position. Figure 6 This is a three-dimensional schematic diagram of the air extraction assembly provided in one embodiment of the present application when the baffle structure 60 is located in the second position. Figure 5 and Figure 6 As shown, the exhaust assembly 40 includes an inner lining structure 50 and a baffle structure 60. Both the inner lining structure 50 and the baffle structure 60 are annular. The inner lining structure 50 is located in the cavity 10 and below the air guide plate 30. The inner lining structure 50 is arranged around the base 20. The inner lining structure 50 encloses a process area. The inner lining structure 50 is also in contact with the cavity wall of the cavity 10 and an exhaust channel 504 is formed therebetween. The exhaust channel 504 is connected to the exhaust port 13.

[0059] A plurality of first air extraction holes 501 and a plurality of second air extraction holes 502 are provided on the side wall of the lining structure 50. Furthermore, when the base 20 is located at the film transfer position, the bearing surface is located below the plurality of second air extraction holes 502. When the base 20 rises to the process position, all the first air extraction holes 501 are located above the bearing surface, and all the second air extraction holes 502 are located below the bearing surface of the base 20. The air extraction port 13 may be located below the plurality of second air extraction holes 502.

[0060] The baffle structure 60 is arranged around the side wall of the lining structure 50, that is, the baffle structure 60 is arranged in the exhaust channel 504, and the baffle structure 60 is lifted and lowered in the vertical direction relative to the lining structure 50, and the baffle structure 60 can selectively block the multiple first exhaust holes 501 or the multiple second exhaust holes 502. In this embodiment, the process chamber 100 can switch between the first working state and the second working state. In the second working state, the baffle structure 60 blocks all the first exhaust holes 501, and all the second exhaust holes 502 are exposed. At this time, the process area is connected to the exhaust channel 504 through the multiple second exhaust holes 502; in the first working state, the baffle structure 60 blocks all the second exhaust holes 502, and all the first exhaust holes 501 are exposed. At this time, the process area is connected to the exhaust channel 504 through the multiple first exhaust holes 501. Of course, when the first exhaust hole 501 and the second exhaust hole 502 are not blocked by the baffle structure 60 , the process area is connected to the exhaust channel 504 through the first exhaust hole 501 and the second exhaust hole 502 .

[0061] Exemplarily, the working process of the process chamber 100 is described in detail by taking the example of performing a cleaning process in the first working state and performing an etching process in the second working state.

[0062] Before the process starts, when transferring the wafer, the base 20 is located at the wafer transfer position, the carrying surface is located below all the second air extraction holes 502, the ejector pins 70 are at the first height, and the robot places the silicon wafer 400 to be processed on the carrying surface.

[0063] When the etching process is performed, as shown in FIG4(a), the process chamber 100 is in the second working state, the baffle structure 60 blocks all the first pumping holes 501, and all the second pumping holes 502 are exposed; the base 20 rises to the process position, the carrying surface and the silicon wafer 400 placed on the carrying surface are located above all the second pumping holes 502 and below all the first pumping holes 501; the etching gas is introduced into the process chamber 100, and the etching gas flows downward from the top of the cavity 10 to the process area. Part of the etching gas reacts with the silicon oxide on the silicon wafer 400 to obtain solid by-products. The remaining etching gas in the process area flows into the pumping channel 504 from the second pumping holes 502 under the driving action of the pump 200, and is then discharged from the pumping port 13 to the outside of the cavity 10. The flow path of the etching gas is shown by the hollow arrow in FIG4(a).

[0064] During the cleaning process, as shown in FIG. 4( b), the etching gas is stopped from being introduced into the process chamber 100; the process chamber 100 is switched from the second working state to the first working state, the baffle structure 60 blocks all the second exhaust holes 502, and all the first exhaust holes 501 are exposed; the base 20 is still located at the process position, and the bearing surface is located above all the second exhaust holes 502 and below all the first exhaust holes 501; the second lifting device drives the ejector pin 70 to move up to the second height, and the ejector pin 70 lifts the silicon wafer 400 and moves it up to Above all the first air pumping holes 501 and close to the air guide plate 30, the temperature of the air guide plate 30 is higher than the room temperature. Due to the heat radiation from the air guide plate 30, the silicon wafer 400 is heated up, and the solid by-products formed on the surface of the silicon wafer 400 during the etching process are decomposed into gaseous by-products by heat. The gaseous by-products flow into the air pump channel 504 from the first air pumping holes 501 under the suction action of the air pump 200, and are then discharged from the air pump port 13 to the outside of the cavity 10. The flow path of the gaseous by-products is shown by the dotted arrow in Figure 4(b).

[0065] After the process is completed, when the wafer is taken out, the ejector pin 70 moves down to the first height, and the silicon wafer 400 returns to the supporting surface of the base 20; the base 20 descends from the process position to the wafer transfer position, and the robot takes away the etched silicon wafer 400.

[0066] In summary, the exhaust assembly 40 of this embodiment is designed with a lining structure 50 and a baffle structure 60, and the lining structure 50 is provided with a plurality of first exhaust holes 501 and a plurality of second exhaust holes 502, and the baffle structure 60 can selectively cover the plurality of first exhaust holes 501 or the plurality of second exhaust holes 502. Moreover, when the base 20 is in the process position, the first exhaust holes 501 are located above the bearing surface, and the second exhaust holes 502 are located below the bearing surface.

[0067] On the one hand, the possibility of the gaseous by-products contacting the base 20 in the process of being discharged from the cavity 10 from the first air extraction hole 501, the air extraction channel 504 and the air extraction port 13 in sequence is greatly reduced, so as to prevent the gaseous by-products from being cooled and forming solid by-products on the base 20, thereby ensuring good cleanliness in the cavity 10 and ensuring product yield. On the other hand, compared with the example shown in FIG. 1 , the first air extraction hole 501 in this embodiment is closer to the air guide plate 30. Due to the heat radiation from the air guide plate 30, the hole wall temperature of the first air extraction hole 501 is relatively high, so as to reduce the risk of the gaseous by-products flowing through the first air extraction hole 501 being cooled and condensed into solid by-products, thereby avoiding part of the first air extraction hole 501 being blocked by solid by-products, so as to ensure that the gas (for example, gaseous by-products) in the cavity 10 can be discharged smoothly.

[0068] On this basis, the maintenance frequency of the cavity 10, the base 20 and the lining structure 50 can be greatly reduced to prevent the process chamber 100 from being shut down for too long due to maintenance, thereby ensuring that the process chamber 100 has a high production efficiency and reducing the impact on the product production cycle.

[0069] In this embodiment, the process chamber 100 may further include a driving device, which is used to drive the baffle structure 60 to rise and fall in the vertical direction, so that the baffle structure 60 switches between the first position and the second position. When the baffle structure 60 is in the first position, it covers all the first exhaust holes 501, and the second exhaust holes 502 are exposed, so that the process chamber 100 can be in the second working state. When the baffle structure 60 is in the second position, it covers all the second exhaust holes 502, and the first exhaust holes 501 are exposed, so that the process chamber 100 can be in the first working state.

[0070] The specific structure of the air extraction assembly 40 will be described in detail below.

[0071] Please continue reading Figure 5 and Figure 6The lining structure 50 includes a first annular lining 51, a first annular plate 52 and a second annular plate 53 which are coaxially arranged. All the first air exhaust holes 501 and all the second air exhaust holes 502 are arranged on the first annular lining 51. The first annular plate 52, the first annular lining 51 and the second annular plate 53 are stacked in sequence from top to bottom. The outer diameter of the first annular plate 52 and the outer diameter of the second annular plate 53 are greater than the outer diameter of the first annular lining 51. Then, the first annular plate 52 and the second annular plate 53 both protrude toward the outside of the first annular lining 51.

[0072] In this embodiment, the baffle structure 60 is sleeved on the outer periphery of the first annular liner 51 to cover the first air extraction hole 501 or the second air extraction hole 502 on the outer side of the first annular liner 51. The baffle structure 60 is located between the first annular plate 52 and the second annular plate 53. The first annular plate 52 is used to limit the vertical upward displacement of the baffle structure 60, and the second annular plate 53 is used to limit the vertical downward displacement of the baffle structure 60.

[0073] In this way, the baffle structure 60 is restricted from moving up and down between the first annular plate 52 and the second annular plate 53 to prevent the baffle structure 60 from moving up or down and falling off the first annular liner 51, thereby ensuring that the baffle structure 60 can play a shielding role and further ensuring that the process chamber 100 can achieve the first working state and the second working state.

[0074] Further, as shown in Figure 4, Figure 5 and Figure 6 As shown, the lining structure 50 may also include a third annular plate 54 and a second annular liner 56. The third annular plate 54 and the second annular liner 56 are both coaxially arranged with the first annular liner 51, and in the vertical direction, the second annular plate 53 is stacked on the second annular liner 56, and the second annular liner 56 is stacked on the third annular plate 54. In other words, the first annular plate 52, the first annular liner 51, the second annular plate 53, the second annular liner 56 and the third annular plate 54 are stacked in sequence from top to bottom. The outer diameter of the third annular plate 54 is greater than the outer diameter of the second annular liner 56, and the first annular plate 52, the second annular plate 53 and the third annular plate 54 all protrude and extend toward the outside of the first annular liner 51 and the second annular liner 56.

[0075] In this embodiment, the first annular plate 52, the first annular liner 51, the second annular plate 53 and the cavity wall of the cavity 10 together form a first circulation space 505. When the baffle structure 60 covers all the first air extraction holes 501 in the first position, the first circulation space 505 is connected to the second air extraction holes 502; when the baffle structure 60 covers all the second air extraction holes 502 in the second position, the first circulation space 505 is connected to the first air extraction holes 501. The second annular plate 53, the second annular liner 56, the third annular plate 54 and the cavity wall of the cavity 10 together form a second circulation space 506, and the air extraction port 13 can be specifically provided on the portion of the cavity wall of the cavity 10 corresponding to the second circulation space 506, and the second circulation space 506 is connected to the air extraction port 13. A notch 531 is provided on the second annular plate 53, and the first circulation space 505 is connected to the second circulation space 506 through the notch 531 to form an air extraction channel 504.

[0076] Combined with the above description, when the baffle structure 60 is in the first position, the process chamber 100 can be in the second working state, and the flow path of the part of the etching gas in the chamber 10 that has not reacted with the silicon wafer 400 is as follows: the etching gas flows downward from the top of the chamber 10, flows through the base 20 and continues to flow downward to the second exhaust hole 502, flows into the first flow space 505 from the second exhaust hole 502, then enters the second flow space 506 through the notch 531, and then flows out of the chamber 10 from the exhaust port 13. The flow path of the etching gas on the lining structure 50 during this process can be referred to Figure 5 When the baffle structure 60 is in the second position, the process chamber 100 can be in the first working state, and the flow path of the gaseous by-products in the cavity 10 is: the gaseous by-products flow downward to the first exhaust hole 501, flow into the first flow space 505 from the first exhaust hole 501, then enter the second flow space 506 through the gap 531, and then flow out of the cavity 10 from the exhaust port 13. The flow path of the gaseous by-products on the lining structure 50 in this process can be referred to Figure 6 Indicated by the solid arrow.

[0077] It can be seen that the first annular plate 52 and the second annular plate 53 have multiple functions. They can not only limit the displacement of the baffle structure 60 in the vertical direction, but also form an exhaust channel 504 together with other components.

[0078] It should be understood that in an embodiment in which the lining structure 50 includes a first annular plate 52, a first annular liner 51, a second annular plate 53, a second annular liner 56 and a third annular plate 54 stacked in sequence from top to bottom, any two adjacent components can be fixedly connected, so that the vacuum assembly 40 has a higher structural stability.

[0079] In some embodiments, the air extraction assembly 40 may be a split structure. Figure 7This is a schematic diagram of an exploded view of an air extraction assembly provided in one embodiment of the present application. Figure 7 In the specific example shown, the first annular liner 51 and the first annular plate 52 are fixedly connected to form an integral structure, and the second annular plate 53, the second annular liner 56 and the third annular plate 54 are fixedly connected to form an integral structure.

[0080] Among them, the first annular liner 51 and the first annular plate 52 can be formed into an integral part by an integrated molding process. In this way, not only can the assembly process of the first annular plate 52 and the first annular liner 51 be omitted, but also, without increasing the cost, it is beneficial to improve the structural strength of the integral part formed by the two. Similarly, the second annular plate 53, the second annular liner 56 and the third annular plate 54 can also be an integral part made by an integrated molding process. Among them, under the premise of no contradiction, the two adjacent components on the exhaust assembly 40 can be connected by welding, clamping, screwing or other connection technologies in the art. For example, the second annular plate 53 is provided with a pin hole, and the top of the second annular liner 56 can be protruding and fixed with a pin shaft, and the pin shaft is tightly matched with the pin hole.

[0081] In other embodiments, the air extraction assembly 40 may also be integrally formed.

[0082] As a further optional embodiment, the second annular liner 56 includes an arc plate, a first stop plate and a second stop plate, one end of the arc plate is connected to the first end of the first stop plate, and the other end is connected to the first end of the second stop plate. The first end to the second end of the first stop plate and the second stop plate extend from the inner circumference of the second annular plate 53 to the outer circumference of the second annular plate 53.

[0083] In this way, the second annular plate 53, the outer surface of the second annular liner 56, the third annular plate 54 and the cavity wall of the cavity 10 together enclose the second circulation space 506, and the second circulation space 506 is arc-shaped. To ensure that the first circulation space 505 can communicate with the second circulation space 506, the notch 531 is correspondingly arranged in the area where the second annular plate 53 and the arc-shaped plate are connected. In this example, the air extraction port 13 arranged on the cavity wall of the cavity 10 can be directly opposite to the arc-shaped plate.

[0084] A film transfer port 55 is formed between the second end of the first stop plate and the second end of the second stop plate, and a transfer port may also be provided on the cavity wall of the cavity 10, the transfer port is directly opposite to the film transfer port 55, and both the transfer port and the film transfer port 55 are configured to allow the silicon wafer 400 to pass through. The film transfer port 55 is located below all the second air extraction holes 502 and all the first air extraction holes 501. It should be noted that under the blocking of the first stop plate and the second stop plate, the second circulation space 506 is isolated from the film transfer port 55.

[0085] Specifically, the working process of the process chamber 100 generally includes the following steps.

[0086] The first lifting device drives the base 20 to move to the wafer transfer position, and the carrying surface can be flush with the bottom surface of the wafer transfer port 55. The robot takes the silicon wafer 400 to be processed by the etching process, and makes the silicon wafer 400 pass through the transmission port and the wafer transfer port 55 in sequence, and then places the silicon wafer 400 on the carrying surface.

[0087] The first lifting device drives the base 20 to move upward to the process position, so that the bearing surface is located above the film transfer port 55 and between the second air extraction hole 502 and the first air extraction hole 501 .

[0088] The first lifting device drives the base 20 to move down to the wafer transfer position, so that the bearing surface can be flush with the bottom surface of the wafer transfer port 55, and the robot takes the silicon wafer 400 that has completed the etching process, so that the silicon wafer 400 is sequentially transferred from the wafer transfer port 55 and the transmission port to the outside of the chamber 10.

[0089] Based on the above, in this embodiment, the vacuum assembly 40 can define the vacuum channel 504 together with the cavity wall of the cavity 10 and also construct a wafer transfer port 55 so that the silicon wafer 400 can be moved into or out of the cavity 10 through the wafer transfer port 55.

[0090] In the lining structure 50 of any of the above embodiments, the first air extraction hole 501 can be specifically arranged at the top of the first annular lining 51, and the first air extraction hole 501 is close to the air guide plate 30. In this way, the flow path of the gaseous by-products flowing to the first air extraction hole 501 is short, and the top of the first annular lining 51 can maintain a relatively high temperature due to its proximity to the air guide plate 30, which is conducive to further reducing the risk of the gaseous by-products condensing into solid by-products when they are cooled when flowing through the first air extraction hole 501.

[0091] In the above embodiment, the arrangement of the first air extraction holes 501 is not limited. Figures 5 to 7 As shown, all the first air extraction holes 501 are arranged on the lining structure 50 to form a circle, and the circle of first air extraction holes 501 has a plurality of first air extraction holes 501 arranged at intervals along the circumference of the lining structure 50. The arrangement of the second air extraction holes 502 can refer to the arrangement of the first air extraction holes 501. Figures 5 to 7 In the example shown, all the second air extraction holes 502 are arranged on the lining structure 50 to form a circle, and the circle of second air extraction holes 502 has a plurality of second air extraction holes 502 spaced apart along the circumference of the lining structure 50 .

[0092] Of course, in other embodiments, the first air extraction holes 501 and the second air extraction holes 502 may also be arranged on the lining structure 50 to form multiple circles, and there is a gap between two adjacent circles in the vertical direction.

[0093] By arranging the first gas extraction holes 501 to form at least one circle and the second gas extraction holes 502 to form at least one circle, part of the etching gas that has not reacted with the silicon wafer 400 can flow evenly along the circumference of the cavity 10 to each second gas extraction hole 502, and the gaseous by-products can also flow evenly along the circumference of the cavity 10 to each first gas extraction hole 501.

[0094] The specific structure of the baffle structure 60 can be implemented in a variety of ways, as long as the baffle structure 60 at the first position can cover all the first air extraction holes 501, and the baffle structure 60 at the second position can cover all the second air extraction holes 502. The specific implementation of the baffle structure 60 is described below by taking the example that both the first air extraction holes 501 and the second air extraction holes 502 are provided with a circle.

[0095] As an optional example, the baffle structure 60 includes an annular baffle. In this example, the first air extraction hole 501 and the second air extraction hole 502 are both set to be circular holes, and the radii of the first air extraction hole 501 and the second air extraction hole 502 are both r. In the vertical direction, the vertical distance between the center of the first air extraction hole 501 and the center of the second air extraction hole 502 in the vertical direction is h, and the height H of the annular baffle in the vertical direction can satisfy: h+r<H<h+2r, so that the annular baffle cannot cover the first air extraction hole 501 and the second air extraction hole 502 at the same time. In order to drive the annular baffle to move, the bottom surface of the annular baffle can be protruding with a transmission rod, and the transmission rod is connected to the driving device in a transmission manner.

[0096] As another alternative example, Figures 5 to 7 As shown, the baffle structure 60 includes a first blocking ring 61, a second blocking ring 62 and a connecting rod 63. The first blocking ring 61 and the second blocking ring 62 are coaxially arranged, the first blocking ring 61 is located above the second blocking ring 62, and the connecting rod 63 is fixedly connected to the first blocking ring 61 and the second blocking ring 62. In this way, when the baffle structure 60 is in the first position, the first blocking ring 61 covers all the first air extraction holes 501. When the baffle structure 60 is in the second position, the second blocking ring 62 covers all the second air extraction holes 502.

[0097] In this example, the first air extraction hole 501 and the second air extraction hole 502 are both set to be circular holes, with the diameter of the first air extraction hole 501 being R1 and the diameter of the second air extraction hole 502 being R2. The height of the first blocking ring 61 along the vertical direction should be greater than or equal to R1, and the height of the second blocking ring 62 along the vertical direction should be greater than or equal to R2.

[0098] It should also be noted that when the baffle structure 60 is in the first position, the second blocking ring 62 can be located below the second air pumping hole 502 or above the second air pumping hole 502. For example, please continue to refer to FIG. Figure 5When the baffle structure 60 is in the first position, the second blocking ring 62 is located below the second air pumping hole 502 and the second blocking ring 62 is in contact with the second annular plate 53, and the second annular plate 53 provides support for the baffle structure 60. At this time, to ensure that the second blocking ring 62 does not block the second air pumping hole 502, the height of the second blocking ring 62 along the vertical direction should also be less than or equal to the minimum distance between the second air pumping hole 502 and the top surface of the second annular plate 53 along the vertical direction. Correspondingly, when the baffle structure 60 is in the second position, the first blocking ring 61 is located above the first air pumping hole 501, and the height of the first blocking ring 61 along the vertical direction should be less than or equal to the minimum distance between the first air pumping hole 501 and the bottom surface of the first annular plate 52 along the vertical direction, to ensure that the first blocking ring 61 does not block the first air pumping hole 501.

[0099] In some embodiments, the diameter R1 of the first air pumping hole 501 may satisfy: 3mm≤R1≤4mm. In some embodiments, the diameter R2 of the second air pumping hole 502 may satisfy: 3mm≤R2≤4mm. The minimum distance between the second air pumping hole 502 and the second annular plate 53 along the vertical direction, and the minimum distance between the first air pumping hole 501 and the first annular plate 52 along the vertical direction are both greater than 5mm. Accordingly, the height of the first blocking ring 61 along the vertical direction and the height of the second blocking ring 62 along the vertical direction can both be 5mm. Alternatively, the height of the first blocking ring 61 along the vertical direction and the height of the second blocking ring 62 along the vertical direction can also be greater than 5mm, and less than or equal to the minimum distance between the second air pumping hole 502 and the second annular plate 53 along the vertical direction.

[0100] Please combine Figures 5 to 7 , the connecting rod 63 can extend in the vertical direction, the top of the connecting rod 63 is connected to the first blocking ring 61, the bottom of the connecting rod 63 extends to the second circulation space 506 via the notch 531, and the bottom of the connecting rod 63 is connected to the driving device. In this way, the notch 531 can not only connect the first circulation space 505 and the second circulation space 506, but also allow the connecting rod 63 to pass through, so as to avoid interference between the connecting rod 63 and the second annular plate 53. The number of the above-mentioned connecting rods 63 and notches 531 is unlimited, for example, Figures 5 to 7 In the embodiment, two connecting rods 63 and two notches 531 are provided, and the two connecting rods 63 correspond to the two notches 531 one by one.

[0101] As disclosed herein, the drive device can provide linear power. For example, the drive device can be implemented by a linear actuator such as a cylinder, an electric push rod, a hydraulic push rod, etc. The installation position of the drive device is not limited. For example, the drive device can be installed outside the cavity 10. For another example, the drive device can also be installed on the lining structure 50. Specifically, in Figure 7In the embodiment, the driving device can be installed on the third annular plate 54 and connected to the bottom end of the connecting rod 63 passing through the notch 531 to drive the connecting rod 63 to move up and down.

[0102] In any of the above-mentioned baffle structures 60, there is a clearance fit between the baffle structure 60 and the lining structure 50. In other words, there is a gap between the inner circumferential surface of the baffle structure 60 and the lining structure 50. By setting the clearance fit between the baffle structure 60 and the lining structure 50, while ensuring that the baffle structure 60 can cover the first air extraction hole 501 or the second air extraction hole 502, the baffle structure 60 will not rub against the lining structure 50 when it moves in the vertical direction relative to the lining structure 50, thereby ensuring the smoothness of the movement of the baffle structure 60.

[0103] In some implementations, the radial dimension of the gap along the lining structure 50 is greater than or equal to 0.1 mm and less than or equal to 0.2 mm. Figure 7 In the specific example shown, the inner diameter of the first blocking ring 61 is larger than the outer diameter of the first annular liner 51, and the difference between the inner diameter of the first blocking ring 61 and the outer diameter of the first annular liner 51 is in the range of 0.1 mm to 0.2 mm. It is worth noting that when the diameters of the first air pumping hole 501 and the second air pumping hole 502 are 5 mm, the size of the gap is much smaller than the opening area of ​​the first air pumping hole 501 and the second air pumping hole 502. Therefore, the gap has little effect on the sealing of the first air pumping hole 501 and the second air pumping hole 502, so that the first air pumping hole 501 can be sealed when the baffle structure 60 is in the first position, and the second air pumping hole 502 can be sealed when the baffle structure 60 is in the second position.

[0104] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A vacuum assembly, the vacuum assembly being applied to a process chamber, the process chamber comprising a cavity and a base located in the cavity; characterized in that: The air extraction assembly includes an annular lining structure and an annular baffle structure; The lining structure is used to be arranged in the cavity and surround the base to enclose a process area, and the lining structure is also used to form an exhaust channel between the lining structure and the cavity wall of the cavity; The side wall of the lining structure has a plurality of first exhaust holes and a plurality of second exhaust holes; the process area is connected with the exhaust channel through the plurality of first exhaust holes and / or the plurality of second exhaust holes; wherein, when the base is located at the process position, the plurality of first exhaust holes are located above the base bearing surface, and the plurality of second exhaust holes are located below the base bearing surface; The baffle structure is disposed around the side wall of the lining structure and can be raised and lowered relative to the lining structure. The baffle structure is used to selectively cover the plurality of first air extraction holes or the plurality of second air extraction holes.

2. The air extraction assembly according to claim 1, characterized in that: The baffle structure comprises a first blocking ring, a second blocking ring and a connecting rod, wherein the first blocking ring is located above the second blocking ring, and the connecting rod is fixedly connected to the first blocking ring and the second blocking ring; The baffle structure can move between a first position and a second position; when the baffle structure is located at the first position, the first blocking ring blocks the multiple first air pumping holes, and the multiple second air pumping holes are exposed; when the baffle structure is located at the second position, the second blocking ring blocks the multiple second air pumping holes, and the multiple first air pumping holes are exposed.

3. The air extraction assembly according to claim 2, characterized in that: At least one circle of the first air exhaust holes and at least one circle of the second air exhaust holes are provided on the side wall of the lining structure, and the first air exhaust holes in each circle are spaced apart along the circumference of the lining structure, and the second air exhaust holes in each circle are spaced apart along the circumference of the lining structure.

4. The air extraction assembly according to claim 3, characterized in that: The first air extraction hole is provided with a circle, the first air extraction hole is a circular hole and its diameter is greater than or equal to 3 mm and less than or equal to 4 mm, and the height of the first blocking ring along the vertical direction is greater than or equal to 5 mm; and / or, The second air extraction holes are provided in a circle, are circular holes with a diameter greater than or equal to 3 mm and less than or equal to 4 mm, and the height of the second blocking ring along the vertical direction is greater than or equal to 5 mm.

5. The air extraction assembly according to claim 1, characterized in that: The lining structure comprises a first annular plate, a first annular liner and a second annular plate which are coaxially arranged, wherein the first annular plate, the first annular liner and the second annular plate are stacked in sequence from top to bottom; The multiple first air extraction holes and the multiple second air extraction holes are all arranged on the first annular lining; the baffle structure is located between the first annular plate and the second annular plate, the first annular plate is used to limit the vertical upward displacement of the baffle structure, and the second annular plate is used to limit the vertical downward displacement of the baffle structure.

6. The air extraction assembly according to claim 5, characterized in that: The liner structure further comprises a third annular plate and a second annular liner coaxially arranged with the first annular liner, the second annular plate is superimposed on the second annular liner, and the second annular liner is superimposed on the third annular plate; The first annular plate, the first annular liner and the second annular plate are used to form a first flow space together with the cavity wall, and the second annular plate, the second annular liner and the third annular plate are used to form a second flow space together with the cavity wall. A notch is provided on the second annular plate, and the first flow space is connected with the second flow space through the notch to form the exhaust channel.

7. The air extraction assembly according to claim 6, characterized in that: The second annular liner comprises an arc-shaped plate, a first stop plate and a second stop plate, one end of the arc-shaped plate is connected to the first end of the first stop plate, and the other end is connected to the first end of the second stop plate; the first end to the second end of the first stop plate and the second stop plate extend from the inner circumferential surface of the second annular plate to the outer circumferential surface of the second annular plate; A film passing port is formed between the second end of the first stop plate and the second end of the second stop plate, the film passing port is connected to the process area, and the film passing port is used for allowing silicon wafers to pass through; and the notch is arranged in the area of ​​the second annular plate corresponding to the arc plate.

8. The air extraction assembly according to claim 6, characterized in that: The first annular plate and the first annular liner are fixedly connected to form an integral structure, and the second annular plate, the second annular liner and the third annular plate are fixedly connected to form an integral structure.

9. The air extraction assembly according to any one of claims 1 to 8, characterized in that: The baffle structure is matched with the side wall gap of the lining structure, and the gap between the baffle structure and the side wall of the lining structure has a radial dimension greater than or equal to 0.1 mm and less than or equal to 0.2 mm.

10. A process chamber, characterized in that: include: A cavity, a base arranged in the cavity, and an air extraction assembly according to any one of claims 1 to 9; An air suction port is provided on the cavity wall of the cavity, and the air suction port is used to be connected to an air suction pump; The lining structure is disposed between the cavity wall and the base and surrounds the cavity wall to form the air extraction channel, and the air extraction channel is communicated with the air extraction port; The base can be raised and lowered, and the base can be raised from below the plurality of second air extraction holes to a process position.

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