Semiconductor workpiece coating apparatus and control method thereof

Abstract

The invention relates to a semiconductor workpiece coating device and a control method thereof, and belongs to the field of semiconductor manufacturing. Comprises: a coating chamber for accommodating a coating liquid; the wafer clamp is used for clamping a wafer and driving the wafer to be immersed in the coating liquid; the wafer clamp comprises a first posture and a second posture, the first posture is the posture of the clamp under the condition that the wafer is gradually immersed in the coating liquid, and the second posture is the posture of the clamp under the condition that the wafer is completely immersed in the coating liquid; in the first posture, the bottom surface of the bottom of the wafer is obliquely arranged relative to the horizontal plane, and the wafer has a first end and a second end higher than the first end; in the second posture, the bottom surface is parallel to the horizontal plane; the gas exhaust assembly is at least arranged in a partial area in the circumferential direction of the wafer in a surrounding manner, and the gas exhaust assembly is provided with a plurality of liquid outlets; the gas exhaust assembly is configured in the mode that the coating liquid flows out of the liquid outlets to form a transverse flow field in the first direction, and the first direction is the direction from the first end to the second end. According to the technical scheme, the coating quality can be improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing, and particularly to a semiconductor workpiece coating device and a control method thereof. Background Art

[0002] A wafer refers to a silicon wafer used for fabricating silicon semiconductor integrated circuits. Its raw material is silicon, and due to its circular shape, it is called a wafer or silicon wafer. During the production process, a coating process, such as electroplating, needs to be performed on the wafer, that is, a layer of conductive metal is coated on the wafer, and subsequent processing will be performed on the conductive metal layer to form conductive lines. As the basic material of a chip, the wafer has extremely high requirements for the coating layer, so the process requirements are also relatively high. When coating the wafer, the uniformity of the coating layer must be ensured to guarantee the quality of the wafer.

[0003] Currently, electroplating devices in the coating process of semiconductor workpieces are mainly divided into two types according to the positions of the anode and cathode. One is a vertical electroplating device, and the other is a horizontal electroplating device. For the horizontal electroplating device, during electroplating, the wafer is placed horizontally with the surface to be plated facing downwards. This facilitates the loading and unloading of the wafer, and since each part of the surface to be plated of the wafer is at the same depth in the plating solution and the pressure at each part is the same, compared with the vertical electroplating device, it can have better electroplating uniformity. However, compared with the trend of miniaturization of semiconductor manufacturing process nodes, such as the development from 16 nanometers to 7 nanometers, the electroplating quality still cannot meet the requirements. Summary of the Invention

[0004] In view of this, the present application provides a semiconductor workpiece coating device and a control method thereof to solve at least one problem in the background art.

[0005] To achieve the above object, the technical solution of the present application is realized as follows: In a first aspect, an embodiment of the present application provides a semiconductor workpiece coating device, including: A coating chamber for containing a coating solution; A wafer fixture for clamping the wafer and driving the wafer to immerse in the coating solution; the wafer fixture includes a first posture and a second posture. The first posture is the posture of the fixture when the wafer gradually immerses in the coating solution, and the second posture is the posture of the fixture when the wafer is fully immersed in the coating solution; in the first posture, the bottom surface of the wafer is inclined relative to the horizontal plane, and the wafer has a first end and a second end higher than the first end; in the second posture, the bottom surface is parallel to the horizontal plane; The gas discharge assembly is at least disposed around a partial area in the circumferential direction of the wafer. The gas discharge assembly has a plurality of liquid outlets. The gas discharge assembly is configured such that the coating liquid flows out from the plurality of liquid outlets to form a transverse flow field in a first direction, and the first direction is the direction from the first end to the second end.

[0006] In an alternative embodiment, the gas discharge assembly includes a support member and a plurality of guiding members disposed on the support member. The guiding members extend in the first direction. The plurality of liquid outlets are located on the support member, and the guiding members are disposed on one side or both sides of the liquid outlets.

[0007] In an alternative embodiment, the guiding members are inclined upward from bottom to top from the first end to the second end.

[0008] In an alternative embodiment, the central angle of the arc formed by the plurality of liquid outlets on the support member is 90°-180°.

[0009] In an alternative embodiment, the length of the connection line between two liquid outlets located at the edge of the support member is 1.2-1.5 times the diameter of the wafer.

[0010] In an alternative embodiment, it further includes a flow equalizing plate and a sealant that are in contact with the gas discharge assembly below. The flow equalizing plate includes a filtering portion and a contact portion that is in contact with the gas discharge assembly. The sealant is located between the gas discharge assembly and the contact portion.

[0011] In a second aspect, an embodiment of the present application provides a control method for the semiconductor workpiece coating device described above. The method includes: Controlling the wafer fixture to drive the wafer to immerse in the coating liquid in a first posture, and switching from the first posture to a second posture after the wafer is immersed in the coating liquid; During the process of the wafer immersing in the coating liquid in the first posture, controlling the flow rate of the liquid outlets to increase from a first preset flow rate to a second preset flow rate; after the wafer is switched from the first posture to the second posture, controlling the flow rate of the liquid outlets to return from the second preset flow rate to the first preset flow rate; the second preset flow rate is greater than the first preset flow rate.

[0012] In an alternative embodiment, the method further includes: During the process of the wafer immersing in the coating liquid in the first posture, controlling the flow rate and flow volume of the fluid at the liquid supplement port at the bottom of the coating chamber; making the flow rate of the fluid flowing out from the liquid supplement port and passing through the vertical flow field formed by the flow equalizing plate be a third preset flow rate; the third preset flow rate is less than the second preset flow rate, and the flow volume of the vertical flow field is greater than the flow volume of the transverse flow field.

[0013] In an alternative embodiment, controlling the wafer chuck to drive the wafer to immerse into the coating liquid in a first posture and switch from the first posture to a second posture after the wafer is immersed in the coating liquid includes: Controlling the wafer chuck such that the movement of the wafer immersing into the coating liquid is a uniform descending movement or a uniformly accelerated descending movement; the speed of the descending movement of the wafer before entering the horizontal state is 45 mm / s - 150 mm / s.

[0014] In an alternative embodiment, the ratio of the second preset flow rate to the first preset flow rate is 2 - 4.

[0015] In the semiconductor workpiece coating device and its control method according to the embodiments of the present application, the wafer chuck is set to include a first posture and a second posture. In the first posture, the bottom surface of the wafer is inclined relative to the horizontal plane. Moreover, the coating device further includes a gas discharge assembly, and the gas discharge assembly has a plurality of liquid outlets; a transverse flow field along a first direction is formed by flowing out through the liquid outlets. During the process of the wafer gradually immersing into the coating liquid in the first posture, the transverse flow field in the first direction combines with the coating liquid in the coating chamber to generate a tendency of the coating liquid to surge at the corner formed among the second end directly facing the wafer of the wafer bottom surface, the coating liquid, and the wafer chuck. As the wafer descends, the coating liquid with directional surging quickly fills the corner, thereby squeezing out the gas at the corner, preventing bubbles from forming at the corner when the wafer is completely immersed in the coating liquid, and further improving the quality of wafer coating.

[0016] Some of the additional aspects and advantages of the present application will be given in the following description, some will become obvious from the following description, or will be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings: Figure 1 is a schematic cross-sectional view of a semiconductor workpiece coating device provided by an embodiment of the present application; Figure 2 is Figure 1 a lateral projection schematic diagram of Figure 3 is Figure 1 a partial cross-sectional view of the gas discharge assembly in (the right end part is cut off); Figure 4 is a top view schematic diagram of the gas discharge assembly in the semiconductor workpiece coating device provided by an embodiment of the present application; Figure 5 is a bottom view schematic diagram of the gas discharge assembly in the semiconductor workpiece coating device provided by an embodiment of the present application; Figure 6 It is a positional relationship diagram between a guiding member and a wafer in the semiconductor workpiece coating device provided by an embodiment of the present application; Figure 7 It is a schematic diagram of the distribution of liquid outlets of the gas discharge assembly in the semiconductor workpiece coating device provided by an embodiment of the present application Figure One ; Figure 8 It is a schematic diagram of the distribution of liquid outlets of the gas discharge assembly in the semiconductor workpiece coating device provided by an embodiment of the present application Figure Two ; Figure 9 It is a schematic diagram of a flow equalizing plate and a seal in the semiconductor workpiece coating device provided by an embodiment of the present application; Figure 10 It is a schematic flowchart of the control method of the semiconductor workpiece coating device provided by an embodiment of the present application; Figure 11 It is a schematic diagram of a vertical direct current field and a transverse flow field in the control method of the semiconductor workpiece coating device provided by an embodiment of the present application.

[0018] Explanation of reference numerals: 10. Coating chamber; 20. Wafer fixture; 30. Gas discharge assembly; 31. Liquid outlet; 32. Guiding member; 321. Guiding strip; 322. First enclosing portion; 323. Second enclosing portion; 33. Supporting member; 40. Wafer; 50. Flow equalizing plate; 51. Abutting portion; 52. Filtering portion; 60. Seal. Detailed embodiments

[0019] To make the technical solutions and beneficial effects of the present application more obvious and understandable, the following will be described in detail by listing specific embodiments. Among them, the drawings are not necessarily drawn to scale, and local features can be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical and scientific fields to which the present application belongs.

[0020] In the description of the present application, the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of simplifying the description of the present application, rather than indicating that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, that is, it cannot be understood as a limitation to the present application.

[0021] In this application, the terms "first" and "second" are used only for the purpose of clear description and should not be construed as indicating the relative importance of the indicated features or the quantity of the indicated technical features. Therefore, the features defined with "first" and "second" may clearly include at least one such feature. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc.; the meaning of "several" is at least one, such as one, two, three, etc., unless otherwise specifically defined.

[0022] In this application, unless otherwise clearly defined, terms such as "installed", "connected", "joined", "fixed", "set" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can also be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0023] In this application, unless otherwise clearly defined, the first feature being "on", "above", "over", "upward", "under", "beneath", "below" or "downward" of the second feature can be that the first feature is in direct contact with the second feature, or the first feature and the second feature are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" or "upward" of the second feature can be that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than the horizontal height of the second feature. The first feature being "under", "beneath" or "downward" of the second feature can be that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0024] To thoroughly understand this application, detailed steps and detailed structures will be presented in the following description to explain the technical solution of this application. The preferred embodiments of this application are described in detail as follows. However, in addition to these detailed descriptions, this application can also have other implementation manners.

[0025] The applicant of this application found during research and development that the component of the wafer carrier in the horizontal electroplating device that holds the wafer protrudes from the bottom surface of the wafer, forming a corner. During the process of gradually immersing the wafer into the electroplating solution, part of the gas accumulates at the corner and cannot be discharged. After the wafer is completely immersed in the coating chamber, air exists between the bottom surface of the wafer and the coating liquid, forming bubbles, resulting in the surface of the wafer to be coated at the bubble position not being able to contact the coating liquid to complete the coating, which affects the electroplating quality. In response to this discovery, the applicant conducted further research and development and proposed the following technical solutions.

[0026] An embodiment of the present application provides a semiconductor workpiece coating device. In this embodiment, the coating device is specifically an electroplating device. Refer to Figures 1 - 3 , the semiconductor workpiece coating device includes: A coating chamber 10 for containing a coating liquid; A wafer fixture 20 for clamping a wafer 40 and driving the wafer 40 to immerse in the coating liquid; the wafer fixture 20 includes a first posture and a second posture. The first posture is the posture of the fixture when the wafer 40 is gradually immersed in the coating liquid, and the second posture is the posture of the fixture when the wafer 40 is completely immersed in the coating liquid; in the first posture, the bottom surface of the bottom of the wafer 40 is inclined relative to the horizontal plane, and the wafer 40 has a first end and a second end higher than the first end; in the second posture, the bottom surface is parallel to the horizontal plane. A gas discharge assembly 30, at least surrounding a partial area in the circumferential direction of the wafer 40, the gas discharge assembly 30 having a plurality of liquid outlets 31; the gas discharge assembly 30 is configured such that the coating liquid flows out from the plurality of liquid outlets 31 to form a transverse flow field in a first direction, and the first direction is the direction from the first end to the second end. Refer to Figure 7 , the first direction is the same as the direction of F1.

[0027] It can be understood that the coating chamber 10 can be made of a corrosion-resistant material, having a sufficient volume to contain the coating liquid and allow the wafer 40 to be completely immersed. The inner wall of the coating chamber 10 is subjected to a smooth treatment to avoid unnecessary turbulence in the coating liquid. A liquid replenishing port (not shown in the figure) is provided at the bottom of the coating chamber 10 for injecting the coating liquid into the chamber; an overflow port is provided at the top for controlling the liquid level height of the coating liquid.

[0028] Specifically, the wafer fixture 20 can include a clamping portion and a driving portion. The clamping portion is made of a material that does not affect the coating effect and can firmly clamp the edge of the wafer 40 without damaging the wafer 40. The driving portion can control the movement of the clamping portion, including up and down movement and angle adjustment. The wafer fixture 20 has two working postures: the first posture and the second posture. The first posture is the posture of the fixture when the wafer 40 is gradually immersed in the coating liquid. At this time, the bottom surface of the bottom of the wafer 40 is inclined relative to the horizontal plane, and the wafer 40 has a first end and a second end higher than the first end. In the first posture, the inclination angle of the wafer 40 is adjustable, usually kept between 3° and 10°, to facilitate the smooth discharge of gas from the corner. The second posture is the posture of the fixture when the wafer 40 is completely immersed in the coating liquid. At this time, the bottom surface is parallel to the horizontal plane.

[0029] The gas discharge assembly 30 is designed to generate a directed lateral flow field during the process of immersing the wafer 40 in the coating liquid. The directed lateral flow field can flow along the inclined bottom surface of the wafer 40 from the first end towards the second end, and quickly fill the corner between the second end of the wafer 40, the coating liquid and the wafer fixture 20. Thus, when the wafer 40 is about to be completely immersed in the coating liquid but not fully immersed, that is, when the second end of the wafer 40 is slightly higher than the liquid level of the coating liquid and the corner is in communication with the air, the directed lateral flow field enables the coating liquid to quickly fill the corner, thereby squeezing out the gas at the corner. Furthermore, it is ensured that when the wafer 40 is completely immersed in the coating liquid, no bubbles are formed at the corner.

[0030] The number of liquid outlets 31 of the gas discharge assembly 30 is determined according to the size of the wafer 40 and the coating requirements. In this embodiment, it can be set to 8 - 24, and they are evenly distributed in a specific area around the wafer 40. The diameter of the liquid outlet 31 can be set to 0.5 mm - 2 mm to generate an appropriate flow rate and flow volume.

[0031] It should be noted that in this embodiment, when the wafer fixture 20 is in the second posture, in the height direction, the liquid outlet 31 is located below the wafer 40 to prevent the first end of the wafer 40 from blocking the coating liquid flowing out from the liquid outlet 31 and forming a lateral flow field. Specifically, in this embodiment, when the wafer fixture 20 is in the second posture, the distance between the liquid outlet 31 and the bottom of the wafer fixture 20 is 2 - 5 mm.

[0032] Specifically, the gas discharge assembly 30 further has a liquid inlet (not shown in the figure) to supply the coating liquid to the liquid outlet 31. Specifically, the diameter of the liquid inlet is larger than the diameter of the liquid outlet 31. In this way, the flow volume of the liquid inlet can meet the flow volume required for the lateral flow fields generated by several liquid outlets 31.

[0033] In some embodiments of the present application, with reference to Figures 3 - 5 , the gas discharge assembly 30 includes a support member 33 and a plurality of guide members 32 provided on the support member 33. The guide members 32 extend in a first direction; a plurality of the liquid outlets 31 are located on the support member 33, and the guide members 32 are arranged on one side or both sides of the liquid outlet 31.

[0034] It can be understood that the support member 33 can be made of a corrosion - resistant material, and its shape is a partial ring, with an appropriate gap left between it and the inner wall of the coating chamber 10. A liquid channel is provided inside the support member 33, which is connected to an external liquid supply system through the liquid inlet, facilitating a stable liquid supply to each liquid outlet 31. The guide members 32 can be made of the same material as the support member 33. Through the arrangement of the guide members 32, the coating liquid can flow along the extension direction of the guide members 32, forming an effective directed flow field to squeeze out the gas at the corner.

[0035] Specifically, the guiding member 32 includes a plurality of guiding bars 321 distributed at intervals. The guiding bars 321 extend in the first direction, and the plurality of guiding bars 321 are parallel to each other. A plurality of liquid outlets 31 are also provided and are all located between two adjacent guiding bars 321. In this way, in addition to the guiding bars 321 guiding the flow of the coating liquid, relatively independent channels can be formed between adjacent guiding bars 321. The coating liquid flowing out of each liquid outlet 31 can flow in its respective channel, thereby forming a transverse flow field in the first direction. The liquid flowing out of each channel has the same direction and will not interfere with each other. Specifically, the end of the guiding bar 321 facing the liquid outlet 31 is an arc surface or a spherical surface. It can be understood that the flow resistance of the liquid on the arc surface or the spherical surface is relatively small. In this way, the resistance of the coating liquid flowing out of the liquid outlet 31 can be reduced, and the flow rate of the coating liquid can be increased.

[0036] In some embodiments of the present application, referring to Figure 6 , the guiding member 32 is inclined upward from the first end to the second end. Specifically, the guiding member 32 is inclined upward from the first end to the second end. At this time, the corner is on the trajectory of the directional transverse flow field formed by the coating liquid flowing out of the guiding member 32. The directional transverse flow field can push the coating liquid in the coating chamber 10 to have a tendency to surge in the first direction. When the wafer 40 continues to descend, the coating liquid surging in the first direction can more directly fill the corner to squeeze out the gas in the corner. In this embodiment, the included angle between the guiding member 32 and the horizontal plane, that is, the inclination angle, can be 15° - 45°. In other embodiments, without changing the angle of the guiding member 32, setting the guiding bars 321 to be inclined upward from the first end to the second end can also achieve this effect.

[0037] Specifically, the guiding member 32 further includes a first enclosing portion 322. The first enclosing portion 322 encloses the liquid outlets 31 from the end far away from the guiding bars 321 of the plurality of liquid outlets 31 to block the coating liquid from flowing in the direction away from the guiding bars 321. In this way, on the one hand, the coating liquid flowing out of the liquid outlet 31 will be blocked by the first enclosing portion 322, so that the coating liquid can flow more concentratedly towards the second end (i.e., the higher end); on the other hand, when the coating liquid flowing towards the first enclosing portion 322 is blocked by the first enclosing portion 322, a reaction force will be generated to push the coating liquid in the opposite direction, that is, towards the second end.

[0038] Specifically, the guiding member 32 further includes a second enclosing portion 323. One end of the second enclosing portion 323 is connected to the first enclosing portion 322, and the other end extends along the first direction. The second enclosing portion 323 can play the same role as the guiding strip 321, and cooperate with the adjacent guiding strip 321 to guide the liquid flowing out of the liquid outlet at the edge to flow along the first direction, thereby forming a transverse flow field along the first direction.

[0039] In some embodiments of the present application, referring to Figure 7 , the central angle of the arc formed by several of the liquid outlets 31 on the support member 33 is 90°-180°.

[0040] It can be understood that this layout enables the liquid outlets 31 to be concentrated in the low-end area when the wafer 40 is immersed in the coating liquid, that is, the first end. In this way, it is beneficial to centrally form a transverse flow field in the first direction and drive the gas to move towards the second end. If the central angle exceeds 180 degrees, the flow direction of the liquid flowing out of the liquid outlet 31 intersects with the first direction, and even the flow direction is changed by the side wall of the guiding member, resulting in a flow field opposite to the transverse flow field in the first direction. As shown by the dotted arrows in Figure 7 , it not only cannot increase the intensity of the flow field in the first direction, but will interfere with the flow field in the first direction and affect the gas removal effect. The transverse flow field is marked as F1 in Figure 7 , and the interference flow field formed by the dotted arrows is marked as F2 in Figure 7 . The angle of the central angle is marked as A in Figure 7 .

[0041] Specifically, the radius of the arc is slightly larger than the radius of the wafer 40, which is beneficial to keeping an appropriate distance between the liquid outlet 31 and the surface of the wafer 40, being able to effectively remove the gas without causing too much impact on the surface of the wafer 40.

[0042] In some embodiments of the present application, referring to Figure 8 , the length of the connection line between two liquid outlets 31 at the edge is 1.2-1.5 times the diameter of the wafer 40.

[0043] This design is beneficial to the transverse flow field formed by the outflow of the gas discharge assembly 30 to cover the entire wafer 40, ensuring that the coating liquid in the transverse flow field can completely fill the corners and improving the gas discharge effect. The length of the connection line between two liquid outlets 31 at the edge is marked as L1 in Figure 8 .

[0044] In some embodiments of the present application, referring to Figure 9, the device further includes a flow equalizing plate 50 and a seal 60 located below and in contact with the gas discharge assembly 30. The flow equalizing plate 50 has a filtering portion 52 and a contact portion 51 in contact with the gas discharge assembly, and the seal 60 is located between the gas discharge assembly 30 and the contact portion 51.

[0045] Specifically, the flow equalizing plate 50 can be made of a porous material and is used to evenly distribute the liquid flowing in from the lower liquid replenishing port to form a more uniform vertical flow field. The contact portion 51 of the flow equalizing plate 50 matches the shape of the bottom of the gas discharge assembly 30, and a sealed connection is achieved through the seal 60 to prevent liquid leakage from the connection. The seal 60 is made of a corrosion-resistant elastic material, such as fluororubber or silicone rubber, and can maintain good sealing performance in the environment of the coating liquid for a long time. The filtering portion 52 of the flow equalizing plate 50 faces the direction of the wafer 40, and its surface area is larger than the surface area of the wafer 40, which is beneficial for the flow field to completely cover the surface of the wafer 40.

[0046] The embodiment of the present application also provides a control method for a semiconductor workpiece coating device. The semiconductor workpiece coating device is the semiconductor workpiece coating device in the previous embodiment. Refer to Figure 10 , the method includes: S801: Control the wafer clamp to drive the wafer to immerse into the coating liquid in a first posture, and switch from the first posture to a second posture after the wafer is immersed in the coating liquid; S802: During the process of the wafer immersing into the coating liquid in the first posture, control the flow rate of the liquid outlet to increase from a first preset flow rate to a second preset flow rate; after the wafer is switched from the first posture to the second posture, control the flow rate of the liquid outlet to return from the second preset flow rate to the first preset flow rate; the second preset flow rate is greater than the first preset flow rate.

[0047] Specifically, in the first posture, the bottom surface of the wafer is inclined relative to the horizontal plane, and the inclination angle can be 3° - 10°. This angle range can effectively guide the gas to flow out to prevent bubble formation and will not cause instability during the immersion process of the wafer 40. The movement trajectory of the wafer clamp 20 is precisely calculated to ensure the smooth immersion of the wafer 40 into the coating liquid and reduce coating unevenness caused by shaking.

[0048] It should be noted that the dynamic adjustment of the flow rate is synchronized with the immersion process of the wafer 40. When the wafer 40 just starts to immerse, the flow rate is low, and as the immersion depth of the wafer 40 increases, the flow rate gradually increases until it reaches the second preset flow rate. This flow rate control strategy can provide the strongest gas discharge effect in the stage where bubbles are most likely to form.

[0049] In some embodiments of the present application, the ratio of the second preset flow rate to the first preset flow rate is 2 - 4.

[0050] Understandably, if the ratio is too small, it is difficult to achieve the design effect. If the ratio is too large, turbulence and splashing are likely to occur, affecting the coating effect. It should be noted that this ratio range has been verified through a large number of experiments and can improve the gas discharge effect while avoiding coating liquid turbulence and splashing caused by excessive flow rate differences.

[0051] Specifically, the first preset flow rate can be 0.5 m / s - 1 m / s, and the second preset flow rate can be 1.5 m / s - 3 m / s. Through a large number of experiments, this preset flow rate can not only squeeze out the gas at the corner but also reduce the impact on the coating process.

[0052] In some embodiments of the present application, the method further includes: During the process of the wafer being immersed in the coating liquid in the first posture, controlling the flow rate and flow volume of the fluid at the liquid supply port at the bottom of the coating chamber; making the flow rate of the fluid flowing out of the liquid supply port and passing through the vertical flow field formed by the flow equalizing plate be the third preset flow rate; the third preset flow rate is less than the second preset flow rate, and the flow volume of the vertical flow field is greater than the flow volume of the horizontal flow field.

[0053] Specifically, the ratio of the third preset flow rate to the second preset flow rate can be 1:2, and the ratio of the flow volume of the vertical flow field to the flow volume of the horizontal flow field can be 3:1.

[0054] Specifically, the third preset flow rate can be 0.75 m / s - 1.5 m / s. The vertical flow field is mainly used to provide a stable coating environment, while the horizontal flow field is mainly used to squeeze out the gas at the corner. The two flow fields cooperate to effectively prevent the bubble problem, thereby improving the coating quality.

[0055] Specifically, the coating liquid forms a vertical flow field because there is a liquid supply port below, and the function of the flow equalizing plate 50 is only to homogenize the metal ions in the coating liquid supplemented by the liquid supply port.

[0056] Furthermore, the purpose of setting the ratio of the third preset flow rate to the second preset flow rate to 1:2 and the ratio of the flow volume of the vertical flow field to the flow volume of the horizontal flow field to 3:1 is: as Figure 11 As shown, the solid arrows are the horizontal flow field, and the dashed arrows are the vertical flow field. The replenishment of metal ions mainly relies on the vertical flow field of the dashed arrows, and the vertical flow field is set to a large flow volume; on the one hand, it can timely replenish the coating liquid in the coating chamber to timely meet the consumption of metal ions during the coating process on the surface to be coated of the wafer. On the other hand, a large flow volume of the vertical flow field can generate a large surging amplitude on the surface of the coating liquid. Then, by setting the horizontal flow field to have a higher flow rate than the vertical flow field, a certain driving force can be generated by the horizontal flow field, so as to push the surging formed by the vertical flow field towards the corner at the bottom of the wafer 40. As the wafer 40 descends, the surging with a certain direction quickly enters the corner, thereby squeezing out the air at the corner. The vertical flow field is attachedFigure 11 Marked as F3 in

[0057] In some embodiments of the present application, controlling the wafer chuck to drive the wafer to immerse into the coating liquid in a first posture and switch from the first posture to a second posture after the wafer is immersed in the coating liquid includes: Controlling the wafer chuck 20 such that the movement of the wafer 40 immersing into the coating liquid is a uniform descending movement or a uniformly accelerated descending movement; the speed of the descending movement of the wafer 40 before entering the horizontal state is 45 mm / s - 150 mm / s.

[0058] It should be noted that the uniform descending movement is applicable to the situation with higher requirements for coating uniformity, while the uniformly accelerated descending movement is applicable to the situation where the coating process needs to be completed quickly. The selection of the descending speed needs to consider factors such as the viscosity of the coating liquid and the wafer size. For example, a larger-sized wafer 40 usually adopts a lower descending speed. Details are not described herein.

[0059] It should be understood that the above embodiments are all exemplary and do not cover all possible implementation manners included in the technical solution of the present application. Without departing from the scope of the disclosure of the present application, various deformations and changes can also be made on the basis of the above embodiments. Similarly, the various technical features of the above embodiments can also be arbitrarily combined to form other embodiments of the present application that may not be explicitly described. Therefore, the above embodiments only represent several implementation manners of the present application and do not limit the protection scope of the patent of the present application.

Claims

1. A semiconductor workpiece coating device, characterized in that, Comprising: A coating chamber for containing a coating liquid; A wafer chuck for clamping a wafer and driving the wafer to immerse in the coating liquid; The wafer chuck includes a first posture and a second posture. The first posture is the posture of the chuck when the wafer gradually immerses in the coating liquid, and the second posture is the posture of the chuck when the wafer is fully immersed in the coating liquid. In the first posture, the bottom surface of the bottom of the wafer is inclined relative to the horizontal plane, and the wafer has a first end and a second end higher than the first end. In the second posture, the bottom surface is parallel to the horizontal plane; A gas discharge assembly, at least surrounding a partial area in the circumferential direction of the wafer. The gas discharge assembly has a plurality of liquid outlets. The gas discharge assembly is configured such that the coating liquid flows out from the plurality of liquid outlets to form a transverse flow field in a first direction, and the first direction is the direction from the first end to the second end.

2. The semiconductor workpiece coating apparatus according to claim 1, wherein The gas discharge assembly includes a support member and a plurality of guiding members provided on the support member. The guiding members extend in the first direction. A plurality of the liquid outlets are located on the support member, and the guiding members are disposed on one side or both sides of the liquid outlets.

3. The semiconductor workpiece coating device according to claim 2, characterized in that, The guiding members are inclined upward from the first end to the second end.

4. The semiconductor workpiece coating apparatus according to claim 2, characterized in that, The central angle of the arc formed by the plurality of liquid outlets on the support member is 90° - 180°.

5. The semiconductor workpiece coating apparatus according to claim 2, characterized in that, The length of the connection line between two liquid outlets located at the edge of the support member is 1.2 - 1.5 times the diameter of the wafer.

6. The semiconductor workpiece coating device according to any one of claims 1-5, characterized in that, It further includes a flow equalizing plate and a seal member that are in contact with the lower part of the gas discharge assembly. The flow equalizing plate includes a filtering part and a contact part that is in contact with the gas discharge assembly. The seal member is located between the gas discharge assembly and the contact part.

7. The control method of the semiconductor workpiece coating device according to any one of claims 1-6, characterized in that, The method includes: Controlling the wafer chuck to drive the wafer to immerse in the coating liquid in the first posture, and switching from the first posture to the second posture after the wafer is immersed in the coating liquid; During the process of the wafer immersing in the coating liquid in the first posture, controlling the flow rate of the liquid outlets to increase from a first preset flow rate to a second preset flow rate. After the wafer is switched from the first posture to the second posture, controlling the flow rate of the liquid outlets to return from the second preset flow rate to the first preset flow rate. The second preset flow rate is greater than the first preset flow rate.

8. The control method of the semiconductor workpiece coating device according to claim 7, characterized in that, The method further includes: During the process of the wafer immersing in the coating liquid in the first posture, controlling the flow rate and flow volume of the fluid at the liquid supplement port at the bottom of the coating chamber. Making the flow rate of the fluid flowing out from the liquid supplement port and passing through the vertical flow field formed by the flow equalizing plate be a third preset flow rate. The third preset flow rate is less than the second preset flow rate, and the flow volume of the vertical flow field is greater than the flow volume of the transverse flow field.

9. The control method of the semiconductor workpiece coating device according to claim 8, characterized in that, The controlling the wafer chuck to drive the wafer to immerse in the coating liquid in the first posture, and switching from the first posture to the second posture after the wafer is immersed in the coating liquid includes: Controlling the wafer chuck such that the movement of the wafer immersing in the coating liquid is a uniform descending movement or a uniformly accelerated descending movement. The speed of the descending movement of the wafer before entering the horizontal state is 45 mm / s - 150 mm / s.

10. The control method of the semiconductor workpiece coating device according to claim 8, characterized in that, The ratio of the second preset flow rate to the first preset flow rate is 2-4.

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