CN119040996A

CN119040996A - Electroplating device

Info

Publication number: CN119040996A
Application number: CN202310616380.0A
Authority: CN
Inventors: 杨宏超; 贾照伟; 金一诺; 汪若飞; 王晖; 王坚
Original assignee: ACM Research Shanghai Inc
Current assignee: ACM Research Shanghai Inc
Priority date: 2023-05-29
Filing date: 2023-05-29
Publication date: 2024-11-29
Also published as: TW202447002A; WO2024244904A1

Abstract

The present invention discloses an electroplating device, comprising a film frame, the film frame comprising an intermediate channel and an intermediate retaining wall defining the intermediate channel, wherein the intermediate retaining wall does not have a circle with the center of the substrate as the center in the orthographic projection area of the plane where the substrate is located. When the substrate is subjected to an electroplating process in the electroplating device, a trajectory formed by any point in the shielding area corresponding to the intermediate retaining wall on the substrate is a circle with the center of the substrate as the center, and since the intermediate retaining wall is designed so that there is no circle with the center of the substrate as the center in the orthographic projection area of the plane where the substrate is located, the rotation trajectory of any point in the shielding area corresponding to the intermediate retaining wall on the substrate will not be completely contained within the orthographic projection area, so that the electric field between any point on the substrate and the anode will not always be shielded by the intermediate retaining wall, and at the same time, the flow field of the electroplating liquid in the shielding area on the substrate will not be significantly reduced, and finally the sudden change of the electroplating thickness in the shielding area on the substrate is greatly weakened, and the change of the electroplating thickness is basically smooth.

Description

Electroplating device

Technical Field

The invention relates to the technical field of semiconductor manufacturing, in particular to an electroplating device.

Background

Referring to fig. 1 to 4, the conventional electroplating apparatus includes an electroplating chamber, a substrate holding device (not shown), a film frame 100', an ion film 200', and the like. The inside of the plating chamber includes a cathode chamber 300 'and an anode chamber 400', the cathode chamber 300 'is formed on the film frame 100', the anode chamber 400 'is positioned below the cathode chamber 300', and the anode 410 'is accommodated in the anode chamber 400'. The ion membrane 200 'is disposed at the bottom of the membrane holder 100' to separate the anode chamber 400 'from the cathode chamber 300'. Metal ions in the anolyte within anode chamber 400' pass through ionic membrane 200' into the catholyte within cathode chamber 300'. When the substrate 500 'is electroplated, the substrate holding device holds the substrate 500' so that the front surface of the substrate 500 'is immersed in the catholyte in the cathode cavity 300'. In the electroplating process, an electric field is formed between the anode 410' and the substrate 500', metal ions such as Cu ²⁺ in the anolyte and the catholyte migrate to the surface of the substrate 500', electrons are obtained from the substrate 500', and the metal ions are plated to the surface of the substrate 500' to form an electroplated layer.

The film frame 100 'has a middle passage 110' penetrating the center of the film frame 100', the middle passage 110' for supplying the plating solution to the middle region of the substrate. The intermediate channel 110' is formed by an intermediate wall 120', the intermediate wall 120' being circular in shape and solid. Referring to fig. 2 and 3, fig. 2 is a schematic top view of the film frame 100', and fig. 3 is a schematic front view of the middle wall 120' of the film frame 100 'projected on the plane F' of the substrate. As can be seen from fig. 3, the intermediate wall 120 'has a circle centered on the center O' of the substrate in the forward projection region P 'of the plane F' of the substrate. The inventors of the present application have recognized that the rotation trajectory of any point, e.g., point a '(the dashed circle where point a' is shown in fig. 3) in the shielding region of the substrate 500 'corresponding to the intermediate retaining wall 120' is completely included in the forward projection region P 'during the rotation of the substrate 500'. The electric field between any point on the substrate in the shielding region and the anode is always shielded by the intermediate barrier wall 120'. Secondly, since the middle retaining wall 120 'is located at the center of the membrane frame 100', is circular, and has no cathode spray hole at the top, the upward flow velocity of the plating solution at the middle retaining wall 120 'is weakest, which significantly reduces the flow field of the plating solution in the shielding region on the substrate, thereby causing abrupt change of plating thickness in the middle region on the substrate 500', and forming circular special pattern distribution in the shielding region. Fig. 4 shows a graph of the thickness of a substrate plated by a conventional plating apparatus after a 12 inch substrate is plated, wherein a region of the 12 inch substrate having a radius of about 20mm to 50mm is a shielding region corresponding to the intermediate wall 120'. As can be seen from fig. 4, there is a significant fluctuation in the plating thickness on the substrate 500' in the masked area, which will form the above-described circular ring-shaped special pattern on the substrate.

Disclosure of Invention

The invention aims to provide an electroplating device which solves the problem that the electroplating thickness on a substrate has abrupt change in the prior art.

In order to solve the above-mentioned problems, an embodiment of the present invention provides an electroplating apparatus, which includes a film frame, wherein the film frame includes a middle channel penetrating the film frame and a middle retaining wall defining the middle channel, and the middle retaining wall does not have a circle centered on the center of the substrate in a front projection area of a plane where the substrate is located.

In the invention, the middle retaining wall of the film frame adopted by the electroplating device is designed in such a way that a circle taking the center of the substrate as the center of the circle does not exist in the orthographic projection area of the plane of the substrate. In this way, when the substrate rotates around the center of the substrate in the cathode cavity formed on the film frame to perform the electroplating process, the track of any point in the shielding area of the substrate corresponding to the middle retaining wall is not completely contained in the orthographic projection area. Therefore, the electric field between any point in the shielding area corresponding to the middle retaining wall on the substrate and the anode can not be always shielded by the middle retaining wall, and the electroplating liquid flow field of the shielding area on the substrate can not be obviously reduced. The abrupt change in plating thickness in the blocked area on the final substrate is greatly weakened and the plating thickness change is substantially smooth.

Additional features and corresponding advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention.

Drawings

FIG. 1 is a schematic cross-sectional view of a conventional electroplating apparatus;

FIG. 2 is a schematic top view of a prior art film frame;

FIG. 3 is a schematic front view of a conventional middle retaining wall projected on a plane of a substrate;

FIG. 4 is a graph showing the measured thickness of a substrate after a conventional film frame is used in a conventional electroplating apparatus;

FIG. 5 is a schematic cross-sectional view of an electroplating apparatus according to a first embodiment of the invention according to example 1;

Fig. 6 is a schematic perspective view of a film frame according to a first embodiment provided in example 1 of the present invention;

Fig. 7 is a schematic top view of a film frame according to a first embodiment provided in example 1 of the present invention;

Fig. 8 is a schematic cross-sectional view of a film frame according to a first embodiment provided in example 1 of the present invention;

Fig. 9 is a schematic front view of an intermediate wall in a plane of a substrate according to a first embodiment of the present invention provided in example 1;

FIG. 10 is a graph showing the measured thickness of a substrate plated by a conventional plating apparatus using a conventional film frame and the plating apparatus of the present invention using the film frame according to the first embodiment of example 1, respectively;

FIG. 11 is a schematic top view of a film frame according to a second embodiment of the invention in example 1;

fig. 12 is a schematic view of an intermediate retaining wall according to a second embodiment of the invention provided in example 1;

FIG. 13 is a graph showing the thickness of a substrate plated by a conventional plating apparatus using a conventional film frame and the plating apparatus of the present invention using the film frame according to the second embodiment of example 1, respectively;

Fig. 14 is a schematic view of an intermediate retaining wall according to a first embodiment of the present invention provided in example 2;

Fig. 15 is a schematic front projection view of an intermediate wall on a plane of a substrate according to a first embodiment of the present invention provided in example 2;

Fig. 16 is a schematic view of an intermediate retaining wall according to a second embodiment of the invention provided in example 2;

fig. 17 is a schematic front projection view of the outer retaining wall provided in embodiment 3 of the present invention on a plane where a substrate is located;

Fig. 18 and 19 are schematic top views of a film frame according to embodiment 3 of the present invention;

Fig. 20 is a schematic perspective view of a film frame according to embodiment 4 of the present invention;

FIG. 21 is a schematic front view showing the projection of the second end of each branch pipe on the plane of the substrate according to embodiment 4 of the present invention, and

Fig. 22 is a schematic top view of a film frame according to embodiment 4 of the present invention.

Detailed Description

Further advantages and effects of the present invention will become apparent to those skilled in the art from the disclosure of the present specification, by describing the embodiments of the present invention with specific examples. While the description of the invention will be described in connection with the preferred embodiments, it is not intended to limit the inventive features to the implementation. Rather, the purpose of the invention described in connection with the embodiments is to cover other alternatives or modifications, which may be extended by the claims based on the invention. The following description contains many specific details for the purpose of providing a thorough understanding of the present invention. The invention may be practiced without these specific details. Furthermore, some specific details are omitted from the description in order to avoid obscuring the invention. It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other.

It should be noted that in this specification, like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Referring to fig. 5 to 7, fig. 5 shows a schematic cross-sectional view of the plating apparatus, fig. 6 shows a schematic perspective view of the film frame, and fig. 7 shows a schematic plan view of the film frame. The plating apparatus provided in this embodiment 1 includes a plating chamber, an anode 410, an ion film 200, a film holder 100, and a substrate holding device (not shown). The plating chamber includes an anode chamber 400 and a cathode chamber 300, the cathode chamber 300 is formed on the film frame 100, the anode chamber 400 is located below the cathode chamber 300, and an anode 410 is accommodated in the anode chamber 400. The ion membrane 200 is disposed at the bottom of the membrane holder 100 and is used for separating the cathode chamber 300 and the anode chamber 400, so that metal ions in the anolyte in the anode chamber 400 enter the catholyte in the cathode chamber 300 through the ion membrane 200 to supplement the metal ions, such as Cu ²⁺, to the cathode chamber 300. The substrate holding device holds the substrate 500 such that the substrate 500 is electroplated within the cathode chamber 300. It should be noted that the anolyte and catholyte are collectively referred to as plating solutions.

The membrane holder 100 includes a central passage 110 extending through the membrane holder 100 and a central retaining wall 120 defining the central passage 110. The membrane holder 100 further includes a sidewall 130 and a plurality of standtubes 140. The sidewall 130 of the membrane holder 100 extends upward to form a cathode cavity 300, and the sidewall 130 is provided with a catholyte inlet 131 (refer to fig. 8). Each of the branch pipes 140 is provided with a liquid supply passage 141 and an injection hole 1423. The liquid supply passage 141 communicates the catholyte inlet 131 with the injection hole 1423. Each of the branch pipes 140 supplies catholyte to the cathode chamber 300 through the injection holes 1423.

Wherein, the first ends of the plurality of branch pipes 140 are spaced apart along the circumference of the sidewall 130 of the membrane holder 100, and the second ends of the plurality of branch pipes 140 are connected to the intermediate retaining wall 120. The intermediate wall 120 is provided with a plurality of liquid outlet holes 121, and the plurality of liquid outlet holes 121 communicate the intermediate passage 110 with the liquid supply passage 141 of each branch pipe 140. The top of the intermediate wall 120 is also fitted with a center cap 180 (see also fig. 5) covering the intermediate channel 110, the center cap 180 comprising a plurality of dispersion holes (not shown) for passing the catholyte of the intermediate channel 110.

When catholyte is supplied to the cathode chamber 300, the catholyte is introduced into the liquid supply passage 141 of each of the branch pipes 140 through the catholyte line 310 (refer to fig. 5 in combination) via the catholyte inlet 131, and enters the cathode chamber 300 through the injection holes 1423 and the liquid outlet 121. Then, the plating solution (plating solution including catholyte and metal ions fed from anolyte) of the cathode chamber 300 is supplied from below to above to the surface of the substrate 500. Wherein the catholyte in the liquid supply channel 141 is supplied to the middle region of the substrate 500 through the center cap 180 after entering the middle channel 110 from the liquid outlet hole 121.

In this embodiment, the manifold 140 has six branches for uniformly distributing the flow of the cathode liquid. In other embodiments, the number of branches 140 may be increased or decreased depending on the actual process requirements.

As shown in fig. 6, the membrane holder 100 further includes an outer ring retaining wall 150, the outer ring retaining wall 150 being surrounded between the middle retaining wall 120 and the side wall 130, and illustratively, a top portion of the outer ring retaining wall 150 is sealingly connected to a bottom portion of a diffusion plate 190 (refer to fig. 5 in combination) to divide the cathode chamber 300 into at least two separate cathode regions. In this embodiment, the membrane holder 100 includes an outer ring retaining wall 150 dividing the cathode cavity 300 into two cathode regions, the region surrounded by the outer ring retaining wall 150 is a first cathode region, and the region between the outer ring retaining wall 150 and the sidewall 130 of the membrane holder 100 is a second cathode region. In other embodiments, the number of retaining walls 150 may be increased or decreased according to the actual process requirements.

The electroplating device further includes an anode retaining wall 420, where the anode retaining wall 420 is disposed in the anode cavity 400 and located below the outer ring retaining wall 150, and the anode retaining wall 420 is configured to divide the anode cavity 400 into a plurality of anode regions, where the plurality of anode regions respectively correspond to the plurality of cathode regions. Referring to fig. 5, in the present embodiment, the electroplating apparatus includes an anode wall 420 dividing the anode cavity 400 into a central first anode region corresponding to the first cathode region and a peripheral second anode region corresponding to the second cathode region.

In the present application, in order to avoid that the electric field between any point in the shielding area of the substrate 500 corresponding to the middle retaining wall 120 and the anode 410 is always shielded by the middle retaining wall 120, the middle retaining wall 120 of the film frame 100 is modified in a related manner, that is, a circle centered on the center of the substrate does not exist in the orthographic projection area of the plane of the substrate where the middle retaining wall 120 of the film frame 100 is located. When the substrate 500 rotates around the center of the substrate in the cathode chamber 300 to perform the plating process, any point in the shielding region of the substrate 500 corresponding to the middle barrier wall 120 rotates around the center of the substrate, and the rotation track formed by the point is a circle centered on the center of the substrate. In the present application, since the middle retaining wall 120 is designed such that a circle centered on the center of the substrate does not exist in the forward projection area of the plane of the substrate, the rotation track of any point in the shielding area of the substrate 500 corresponding to the middle retaining wall 120 will not be completely included in the forward projection area. This design prevents the electric field between any point of the shielding region of the substrate 500 corresponding to the intermediate barrier wall 120 and the anode 410 from being always shielded by the intermediate barrier wall 120, so that the flow field of the plating solution in the shielding region of the substrate 500 is not significantly reduced. Eventually, the abrupt change in plating thickness in the blocked area on the substrate 500 is significantly reduced or even eliminated. That is, the plating thickness variation is substantially smooth, achieving the objective of improving the uniformity of the plating thickness. It should be noted that, the middle retaining wall 120 is in the orthographic projection area of the plane of the substrate, that is, the shielding area of the middle retaining wall 120 to the substrate.

Example 1:

In this embodiment, the middle retaining wall 120 of the film frame 100 includes an inner contour 1201 and an outer contour 1202, and there is no annular area between the outer contour 1202 and the inner contour 1201 on the cross section of the middle retaining wall 120, so that there is no circle centered on the center of the substrate in the orthographic projection area of the plane of the substrate on which the middle retaining wall 120 is located.

Fig. 9 is a schematic diagram showing an orthographic projection of the intermediate wall on a plane of the substrate in the first embodiment of the present embodiment. In fig. 9, the oblique line portion is a forward projection region P1 of the intermediate wall, and the intermediate wall 120 is marked in fig. 9 for convenience. Specifically, in the first embodiment, as shown in fig. 9, the shape of the inner contour 1201 of the middle retaining wall 120 is consistent with the shape of the outer contour 1202, for example, the shape of each of the inner contour 120and the shape of each of the outer contour 1202 of the middle retaining wall 120 are regular hexagons, and the inscribed circle 12022 of the outer contour 1202 of the middle retaining wall 120 is smaller than the circumscribed circle 12011 of the inner contour 1201, in which case there is no annular region between the inscribed circle 12022 of the outer contour 1202 and the circumscribed circle 12011 of the inner contour 1201 on the cross section of the middle retaining wall 120, no matter whether the middle retaining wall 120 is eccentrically disposed or centrally disposed with respect to the center O1 of the substrate, the orthographic projection region P1 of the plane of the middle retaining wall 120 on the substrate will not have a circle centered on the center O1 of the substrate. The blocking of the substrate by the intermediate wall 120 according to the first embodiment will be described with continued reference to fig. 9. Firstly, any point, such as point A1, in a shielding area (located between an inscribed circle of the inner contour 1201 and an circumscribed circle of the outer contour 1202) of the corresponding hexagonal middle retaining wall 120 on the substrate is taken. When the substrate rotates around the center O1 of the substrate in the cathode chamber to perform the plating process, the rotation locus of the point A1 is a circle (a dotted circle where the point A1 is located in fig. 9) centered on the center O1 of the substrate. Since the intermediate wall 120 does not have a circle centered on the center O1 of the substrate in the forward projection region P1 of the plane of the substrate, the rotation locus of the point A1 is not completely contained in the forward projection region P1, but is partially contained in the forward projection region P1 and partially outside the forward projection region P1. Therefore, the electric field between any point of the shielding area and the anode on the substrate is not always shielded by the regular hexagonal middle retaining wall 120, and the electroplating liquid flow field of the shielding area is not obviously reduced, so that the electroplating thickness variation of the shielding area on the electroplated substrate is basically smooth.

In an embodiment not shown in the figures, the shape of the inner contour 1201 and the shape of the outer contour 1202 of the intermediate wall 120 may also be other polygons, such as regular pentagons, squares, regular triangles, etc.

Fig. 10 is a graph showing the thickness of a substrate plated by using a film frame 100 'with a circular shape of a middle retaining wall 120' and a film frame 100 with a regular hexagon shape of a middle retaining wall 120 in the conventional electroplating apparatus. In fig. 10, the abscissa indicates the radius of the substrate 500, and the ordinate indicates the plating thickness. As can be seen from FIG. 10, after the conventional electroplating apparatus performs an electroplating process on a 12-inch substrate under the same process parameters, the shielding region of the 12-inch substrate corresponding to the middle retaining wall 120' is approximately located in a region with a radius ranging from 20mm to 50mm on the substrate, and the electroplating thickness in the shielding region has obvious fluctuation. Therefore, the middle barrier wall 120 is provided in a regular hexagon shape, which can effectively improve the uniformity of the plating thickness.

Referring to fig. 11 and 12, fig. 11 shows a schematic top view of a membrane holder in a second embodiment of the present embodiment, and fig. 12 shows a schematic view of an intermediate retaining wall in the second embodiment of the present embodiment. In the second embodiment, as shown in fig. 11 and 12, the shape of the inner contour 1201 of the intermediate wall 120 is identical to the shape of the outer contour 1202, and is elliptical. In addition, in the second embodiment, the ratio of the major axis to the minor axis of the ellipse is greater than or equal to 1.5, and the difference between the major axis and the minor axis of the ellipse is greater than 2 times the thickness d1 of the intermediate retaining wall 120, in which case, as shown in fig. 12, there is no annular region between the outer contour 1202 and the inner contour 1201 of the intermediate retaining wall 120 in the cross section of the intermediate retaining wall 120, and no circle centered on the center O1 of the substrate exists in the orthographic projection region of the plane of the substrate regardless of whether the intermediate retaining wall 120 is disposed eccentrically or centrally with respect to the center O1 of the substrate. Thus, when the substrate rotates, the electric field between any point in the shielding area of the substrate corresponding to the elliptical middle retaining wall 120 and the anode is not always shielded by the elliptical middle retaining wall 120, so that the electroplating liquid flow field of the shielding area is not obviously reduced, and finally, the electroplating thickness variation of the shielding area on the electroplated substrate is basically smooth. In the present embodiment, the outer contour 1202 of the elliptical middle retaining wall 120 is concentric with the inner contour 1201 and has the same shape, so that the two contours are parallel, and the thickness d1 of the middle retaining wall 120 is the distance between the inner contour 1201 and the outer contour 1202 of the middle retaining wall 120.

Fig. 13 is a graph showing the thickness of plating on a substrate after the conventional plating apparatus has plated the substrate using a film frame having a circular center wall shape and the plating apparatus of the present application has plated the substrate using a film frame having an elliptical center wall shape. In fig. 13, the abscissa indicates the radius of the substrate, and the ordinate indicates the plating thickness. As can be seen from FIG. 13, after the electroplating process is performed on the 12 inch substrate by the conventional electroplating device under the same process parameters, the shielding area of the 12 inch substrate corresponding to the middle retaining wall is approximately located in the area with the radius ranging from 20mm to 50mm on the substrate, and obvious fluctuation occurs in the electroplating thickness in the shielding area. Therefore, the elliptical middle retaining wall can effectively improve the uniformity of the electroplating thickness.

Example 2:

Referring to fig. 14 and 15, fig. 14 is a schematic view of the intermediate wall provided in embodiment 2, and fig. 15 is a schematic view of the intermediate wall provided in embodiment 2 in front projection on a plane of the substrate. In fig. 15, the hatched portion is the forward projection area when the intermediate wall as a reference coincides with the center of the substrate, the hatched portion is the actual forward projection area P2 of the intermediate wall, and the intermediate wall 120 is marked in fig. 15 for convenience. In the film frame provided in this embodiment 2, the middle retaining wall 120 is eccentrically disposed with respect to the center O1 of the substrate, a first annular region exists between the outer contour 1202 and the inner contour 1201 of the middle retaining wall 120 on the cross section of the middle retaining wall 120, and the eccentricity of the middle retaining wall 120 is greater than half the thickness d2 of the first annular region, where the center of the middle retaining wall 120 is denoted by O2. Specifically, in the first embodiment of the present embodiment, as shown in fig. 15, the inner contour 1201 and the outer contour 1202 of the middle retaining wall 120 are identical in shape, for example, are all circular, and the outer contour 1202 and the inner contour 1201 of the middle retaining wall 120 form a first annular region, and the eccentricity of the middle retaining wall 120 is greater than one half of the thickness d2 of the first annular region, so that a circle centered on the center O1 of the substrate does not exist in the orthographic projection region P2 of the plane of the middle retaining wall 120. Next, a description will be given of the case of shielding the substrate by the intermediate retaining wall 120 according to the first embodiment of the present embodiment with continued reference to fig. 15. Any point, for example, A2 point, in the shielding region (region between a small circle formed by the point of the intermediate wall 120 closest to the substrate center O1 around O1 and a large circle formed by the point of the intermediate wall 120 farthest from the substrate center O1) corresponding to the intermediate wall 120 is taken. When the substrate rotates around the center of the substrate in the cathode cavity to perform the electroplating process, the rotation track of the point A2 is a circle (the dotted circle where the point A2 is located in fig. 15) with the center O1 of the substrate as the center, and since the center retaining wall 120 does not exist in the orthographic projection area P2 on the plane where the substrate is located with the center O1 of the substrate as the center, the rotation track of the point A2 is not completely contained in the orthographic projection area P2, but is partially contained in the orthographic projection area P2, and is partially outside the orthographic projection area P2, so that the electric field between the point A2 and the anode is not always blocked by the eccentric center retaining wall 120, and finally, the plating thickness mutation of the blocking area where the rotation track of the point A2 is located on the substrate is weakened to a great extent or even has no mutation, thereby achieving the purpose of improving the plating thickness uniformity.

Fig. 16 shows a schematic view of an intermediate retaining wall according to a second embodiment of the present invention. Specifically, in the second embodiment of the present embodiment, the inner contour 1201 of the middle retaining wall 120 is inconsistent with the outer contour 1202, for example, the inner contour 1201 of the middle retaining wall 120 is square, the outer contour 1202 of the middle retaining wall 120 is hexagonal, a first annular region exists between the inner contour 1201 and the outer contour 1202 of the middle retaining wall 120, and the first annular region is formed by an inscribed circle 12022 of the outer contour 1202 and an circumscribed circle 12011 of the inner contour 1201, and the eccentricity of the middle retaining wall 120 is greater than one half of the thickness d2 of the first annular region, so that a circle centered on the center of the substrate does not exist in the orthographic projection region of the plane of the middle retaining wall 120.

It should be noted that, the eccentricity of the middle retaining wall 120 is the distance between the center O2 of the middle retaining wall 120 in the orthographic projection area of the plane of the substrate and the center O1 of the substrate.

Example 3:

In this embodiment, in order to avoid that an electric field between any point in a shielding area corresponding to the outer ring retaining wall on the substrate and the anode is always shielded by the outer ring retaining wall, the outer ring retaining wall of the film frame is improved in a related manner, that is, a circle taking the center of the substrate as the center of a circle does not exist in the orthographic projection area of the plane of the substrate. Fig. 17 shows a schematic view of an outer retaining wall according to an embodiment of example 3. The contour line arrangement of the outer ring retaining wall 150 shown in fig. 17 is similar to that of the middle retaining wall according to the first embodiment of example 1, as shown in fig. 17, the shape of the inner contour 1501 of the outer ring retaining wall 150 is identical to that of the outer contour 1502 of the outer ring retaining wall 150, for example, the inner contour 15022 of the outer ring retaining wall 150 is regular hexagon, and the inscribed circle 15022 of the outer contour 1502 of the outer ring retaining wall 150 is smaller than the circumscribed circle 15011 of the inner contour 1501, in which case, no annular area exists between the inscribed circle 15022 of the outer ring retaining wall 150 and the circumscribed circle 15011 of the inner contour 1501 on the cross section of the outer ring retaining wall 150, and no matter whether the outer ring retaining wall 150 is eccentrically arranged or centrally arranged with respect to the center O1 of the substrate, no circle with the center O1 of the substrate as the center exists in the orthographic projection area of the plane of the substrate is present on the outer ring retaining wall 150, so that the electric field between any point in the shielding area of the corresponding outer ring retaining wall 150 on the substrate and the anode is not always shielded by the outer ring retaining wall 150, thereby achieving the purpose of improving the uniformity of the plating thickness of the shielding area.

Specifically, for example, in the specific example shown in fig. 18, there is a space between the six corners of the outer ring retaining wall 150 and the side wall 130 of the membrane holder 100, accordingly, the structure of the anode retaining wall may be identical to the structure of the outer ring retaining wall 150, there is a space between the six corners of the anode retaining wall and the side wall of the anode cavity, and the anode retaining wall corresponds up and down to the outer ring retaining wall 150, and as in the specific example shown in fig. 19, the structure of the outer ring retaining wall 150 is similar to the inscribed hexagon of the side wall 130 of the membrane holder 100, accordingly, the structure of the anode retaining wall may be similar to the inscribed hexagon of the side wall of the anode cavity, and the anode retaining wall corresponds up and down to the outer ring retaining wall 150.

It should be noted that fig. 18 and 19 are only examples, and are not intended to limit the specific arrangement of the retaining wall 150. In addition, the specific form of the contour line of the outer ring retaining wall 150 may be similar to that of the intermediate retaining wall in the above-described embodiments 1 and 2, and the contour line arrangement of the intermediate retaining wall and the description of the shielding condition of the substrate by the intermediate retaining wall in the above-described embodiments 1 and 2 may be applied to the outer ring retaining wall 150. For example, the outer ring retaining wall 150 may also be disposed in the form of the intermediate retaining wall in embodiment 2, specifically, there is a second annular region between the outer contour 1502 and the inner contour 1501 of the outer ring retaining wall 150 in the cross section of the outer ring retaining wall 150, and the outer ring retaining wall 150 is disposed eccentrically with respect to the center O1 of the substrate, wherein the eccentricity of the outer ring retaining wall 150 is greater than one half of the thickness of the second annular region.

Example 4:

Referring to fig. 20 to 22, fig. 20 is a perspective view showing a film frame provided in embodiment 4, fig. 21 is a front projection view showing a plane of a substrate at which a second end of each branch pipe provided in embodiment 4 is located, and fig. 22 is a perspective view showing a film frame provided in embodiment 4. The intermediate wall of the film frame 100 of the plating apparatus provided in this embodiment 4 is discontinuous in the circumferential direction. In contrast, the intermediate wall of examples 1-3 is circumferentially continuous.

In the particular example shown in fig. 20, the second ends of the respective legs 140 are spaced apart along the circumference of the intermediate channel 110, and the second ends of the respective legs 140 collectively define a circumferentially discontinuous intermediate wall. The second end (i.e., the intermediate wall intermittent in the circumferential direction) of each of the branch pipes 140 is provided with a liquid outlet hole 121 toward the intermediate passage 110 to supply catholyte to the intermediate passage 110. In this example, the cross-section of the intermediate channel 110 defined by the second end of each branch 140 is similar to a circle, and in other embodiments, the cross-section of the intermediate channel 110 defined by each branch 140 may be hexagonal, elliptical, triangular, or the like, depending on the arrangement of the branches 140 and the shape of the second end of each branch 140.

As shown in fig. 21, the orthographic projection of the second end of each branch pipe 140, i.e., the middle retaining wall, projected on the plane of the substrate does not have a circle centered on the center O1 of the substrate. The blocking condition of the substrate by the intermediate wall according to the present embodiment will be described with reference to fig. 21. When the substrate rotates around the center of the substrate in the cathode cavity to perform the electroplating process, for example, the point A3 corresponds to any point in the shielding area of the intermediate retaining wall, the rotation track of the point A3 is a circle (a dotted line circle where the point A3 is located in fig. 21) with the center O1 of the substrate as the center, and since the intermediate retaining wall does not have a circle with the center O1 of the substrate as the center in the orthographic projection area of the plane where the substrate is located, the rotation track of the point A3 is not completely included in the orthographic area. The electric field between any point on the substrate in the shielded region and the anode is not always shielded by the second ends of the branches 140. Meanwhile, the plating solution flow field of the shielding area corresponding to the second end of each branch pipe 140 on the substrate is not obviously reduced, and finally the plating thickness of the shielding area on the substrate is greatly weakened, the plating thickness is suddenly reduced or even not suddenly changed, and the plating thickness change is basically smooth, so that the purpose of improving the plating thickness uniformity of the substrate is achieved.

Specifically, as shown in fig. 22, the ratio of the distance d3 between the second ends of the branch pipes 140 to the thickness d4 of the branch pipes 140 is not less than a critical minimum value, which is the ratio of the distance between the second ends of the branch pipes 140 to the thickness of the branch pipes 140 at least when the uniformity of the plating thickness of the substrate meets the plating process requirements. Preferably, the critical minimum is 50%, i.e. d3/d4 x 100% >50%.

It should be noted that the above embodiments are merely for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the technical solution described in the above embodiments may be modified or some or all of the technical features may be equivalently replaced, and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present invention.

Claims

1. An electroplating device, characterized in that it comprises a film frame, wherein the film frame comprises an intermediate channel penetrating the film frame and an intermediate retaining wall defining the intermediate channel, wherein the intermediate retaining wall does not have a circle with the center of the substrate as the center in the orthographic projection area of the plane where the substrate is located.

2. The electroplating device according to claim 1 is characterized in that the intermediate retaining wall comprises an inner contour and an outer contour, and there is no annular area between the outer contour and the inner contour of the intermediate retaining wall on the cross section of the intermediate retaining wall.

3. The electroplating device according to claim 2 is characterized in that the shape of the inner contour of the intermediate retaining wall is consistent with the shape of the outer contour and is a polygon, and the inscribed circle of the outer contour of the intermediate retaining wall is smaller than the circumscribed circle of the inner contour.

4. The electroplating device according to claim 2 is characterized in that when the shape of the inner contour of the middle retaining wall is consistent with the shape of the outer contour and is an ellipse, and the ratio of the major axis to the minor axis of the ellipse is greater than or equal to 1.5.

5. The electroplating device according to claim 4 is characterized in that the difference between the major axis and the minor axis of the ellipse is greater than twice the thickness of the middle retaining wall.

6. The electroplating device according to claim 1 is characterized in that the intermediate retaining wall includes an inner contour and an outer contour, and there is a first circular ring area between the outer contour and the inner contour of the intermediate retaining wall on the cross section of the intermediate retaining wall; wherein the intermediate retaining wall is eccentrically arranged relative to the center of the substrate, and the eccentricity of the intermediate retaining wall is greater than one half of the thickness of the first circular ring area.

7. The electroplating device according to claim 1 is characterized in that the membrane frame also includes side walls and an outer ring retaining wall, the side walls extend upward to form a cathode cavity, and the outer ring retaining wall is arranged between the middle channel of the membrane frame and the side walls of the membrane frame to separate the cathode cavity into at least two independent cathode areas.

8. The electroplating device according to claim 7 is characterized in that there is no circle with the center of the substrate as the center in the orthographic projection area of the outer ring retaining wall on the plane where the substrate is located.

9. The electroplating device according to claim 8 is characterized in that the outer ring retaining wall comprises an inner contour and an outer contour, and there is no annular area between the outer contour and the inner contour of the outer ring retaining wall on the cross section of the outer ring retaining wall.

10. The electroplating device according to claim 8 is characterized in that the outer ring retaining wall includes an inner contour and an outer contour, and there is a second circular ring area between the outer contour and the inner contour of the outer ring retaining wall on the cross section of the outer ring retaining wall; wherein the outer ring retaining wall is eccentrically arranged relative to the center of the substrate, and the eccentricity of the outer ring retaining wall is greater than one half of the thickness of the second circular ring area.

11. The electroplating device according to claim 1 is characterized in that the middle retaining wall of the membrane frame is discontinuous along the circumferential direction.

12. The electroplating device according to claim 11 is characterized in that the membrane frame also includes a plurality of branch tubes, the second end of each branch tube is arranged at intervals along the circumference of the middle channel, and the second end of each branch tube is jointly defined as the middle retaining wall that is discontinuous along the circumferential direction.

13. The electroplating device according to claim 12 is characterized in that the ratio of the spacing between the second ends of each branch tube to the thickness of each branch tube is not less than a critical minimum value, and the critical minimum value refers to the ratio of the spacing between the second ends of each branch tube to the sum of the thickness of each branch tube when at least the uniformity of the electroplating thickness of the substrate meets the requirements of the electroplating process.

14. The electroplating device according to claim 13, characterized in that the critical minimum value is 50%.