CN117488385A - Wafer electroplating device and cleaning method in electroplating process - Google Patents

Abstract

The application provides a wafer electroplating device and a cleaning method in an electroplating process, wherein the electroplating device comprises a wafer clamp, an electroplating cavity protective cover, a liquid storage tank, a water blocking ring and a liquid sprayer, the wafer clamp is suitable for enabling a wafer to reach a spin-drying height and rotate at a first speed to perform spin-drying operation, and driving the wafer to reach a flushing height and rotate at a second speed to perform flushing operation; the opening of the electroplating cavity protecting cover is provided with a first height along the vertical direction between the opening and the liquid level of the electroplating liquid; the water blocking ring is arranged above the liquid storage tank, the inner diameter of the water blocking ring is provided with a second height along the vertical direction between the water blocking ring and the liquid level of the electroplating liquid, the second height is larger than the spin-drying height, and the second height is smaller than the flushing height; the nozzle of the liquid sprayer is provided with a third height between the vertical direction and the liquid level of the electroplating liquid, the liquid sprayer is used for spraying cleaning liquid to the wafer to clean the wafer, the third height is larger than the second height, and the third height is smaller than the flushing height. The utility model reduces the throwing amount and the water precipitation amount of the electroplating solution.

Description

Wafer electroplating device and cleaning method in electroplating process

Technical Field

The invention relates generally to the field of semiconductor manufacturing, and more particularly to a wafer electroplating device and a cleaning method in an electroplating process.

Background

In the field of semiconductor manufacturing, an effective cleaning process is critical to wafer yield. After the wafer is electroplated, the electroplating solution attached to the wafer and the wafer clamp needs to be removed by spin-drying, cleaning with a cleaning solution, and the like. A portion of the cleaning solution used during the cleaning process is drained from the plating chamber and a portion falls back into the reservoir (i.e., falls into the water) thereby diluting the plating solution. As the number of cleaning processes in the plating chamber increases, the concentration of the plating solution gradually decreases, which affects the stability of the plating process. In addition, during spin-drying, part of the electroplating solution is thrown out of the liquid storage tank, which leads to waste of the electroplating solution; on the other hand, the thrown electroplating solution can increase the cost of sewage treatment.

Therefore, in order to increase the stability of the plating process and to reduce the sewage treatment cost, the amount of water falling from the cleaning liquid and the amount of the plating liquid to be thrown out should be reduced.

Disclosure of Invention

The invention aims to provide a wafer electroplating device capable of reducing the water fall and the throwing amount of plating solution and a cleaning method in an electroplating process.

In order to solve the technical problems, the invention provides a wafer electroplating device, which is characterized by comprising a wafer clamp, an electroplating cavity protective cover, a liquid storage tank, a water blocking ring and a liquid sprayer, wherein the wafer clamp is arranged in an inner space of the electroplating cavity protective cover in a vertical direction in a lifting manner, and is suitable for driving the wafer to reach a spin-drying height and rotating at a first speed to perform spin-drying operation, and driving the wafer to reach a rinsing height and rotating at a second speed to perform rinsing operation, and the rinsing height is larger than the spin-drying height; the opening of the electroplating cavity protecting cover is provided with a first height along the vertical direction and between the electroplating liquid level; the liquid storage tank is positioned at the bottom of the electroplating cavity protective cover and is used for containing the electroplating liquid; the water retaining ring is arranged above the liquid storage tank, and a second height is arranged between the inner diameter of the water retaining ring and the liquid level of the electroplating liquid along the vertical direction, wherein the second height is larger than the spin-drying height, and the second height is smaller than the flushing height; the spray device is arranged on the side wall of the electroplating cavity protective cover, a third height is arranged between the spray nozzle of the spray device and the liquid level of the electroplating liquid along the vertical direction, the spray device is used for spraying cleaning liquid to the wafer to clean the wafer, the third height is larger than the second height, and the third height is smaller than the flushing height.

In an embodiment of the present application, the first height ranges from 180-230mm.

In an embodiment of the application, the opening of the plating chamber protecting cover has a first diameter, the water retaining ring has a first inner diameter, and a difference between the first inner diameter and the first diameter is greater than or equal to 0mm and less than or equal to 3mm.

In an embodiment of the present application, the first diameter ranges from 390-410mm.

In one embodiment of the present application, the plating chamber shield has a removable top assembly.

In an embodiment of the present application, the second height is in the range of 35-55mm.

In an embodiment of the present application, the water retaining ring has a first included angle with the horizontal plane, and the first included angle ranges from 20 ° to 40 °.

In one embodiment of the present application, the water deflector ring has a width in the range of 82-102mm.

In an embodiment of the present application, the third height is in the range of 45-65mm.

In an embodiment of the present application, the liquid sprayer has a preset length, and the preset length ranges from 77 mm to 97mm.

In one embodiment of the present application, the liquid sprayer has a second angle with the horizontal, the second angle ranging from 16 ° to 30 °.

In an embodiment of the present application, the first speed is greater than the second speed.

The present application also provides a cleaning method in a wafer plating process, which is characterized in that the method is performed by using the wafer plating device as described above, and includes: the wafer clamp drives the wafer to reach a spin-drying height and rotates at a first speed to perform spin-drying operation; after the spin-drying operation is finished, the wafer clamp drives the wafer to reach a washing height and rotates at a second speed to perform the washing operation, and the washing height is larger than the spin-drying height.

The wafer electroplating device of this application has improved these three kinds of heights on the whole through setting up the first height of the open-ended of electroplating chamber safety cover, the second height of the internal diameter of water retaining ring and the third height of the nozzle of hydrojet ware for wafer anchor clamps are located completely under the second height when spin-drying operation, have reduced the throwing out amount of plating solution, and make not have water smoke spill and lower water yield when washing the operation. The wafer electroplating device reduces the waste of the electroplating liquid, reduces the cost of sewage treatment, also reduces the water falling amount, and is beneficial to improving the service cycle of the electroplating liquid.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the invention. In the accompanying drawings:

FIG. 1 is a schematic front view of a wafer plating apparatus during a spin-drying operation;

FIG. 2 is a schematic front view of a wafer plating apparatus during a rinsing operation;

FIG. 3 is a schematic front view of a wafer plating apparatus according to an embodiment of the present disclosure during a plating operation;

FIG. 4 is a schematic front view of a wafer plating apparatus according to an embodiment of the present disclosure during a spin-drying operation;

FIG. 5 is a schematic front view of a wafer plating apparatus according to an embodiment of the present disclosure during a rinsing operation;

fig. 6 is a schematic perspective view of a wafer plating apparatus according to an embodiment of the present application.

Detailed Description

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are used in the description of the embodiments will be briefly described below. It is apparent that the drawings in the following description are only some examples or embodiments of the present application, and it is obvious to those skilled in the art that the present application may be applied to other similar situations according to the drawings without inventive effort. Unless otherwise apparent from the context of the language or otherwise specified, like reference numerals in the figures refer to like structures or operations.

As used in this application and in the claims, the terms "a," "an," "the," and/or "the" are not specific to the singular, but may include the plural, unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that the steps and elements are explicitly identified, and they do not constitute an exclusive list, as other steps or elements may be included in a method or apparatus.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless it is specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

In the description of the present application, it should be understood that, where azimuth terms such as "front, rear, upper, lower, left, right", "transverse, vertical, horizontal", and "top, bottom", etc., indicate azimuth or positional relationships generally based on those shown in the drawings, only for convenience of description and simplification of the description, these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present application; the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "upper surface at … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations of "above … …" and "below … …". The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In addition, the terms "first", "second", etc. are used to define the components, and are merely for convenience of distinguishing the corresponding components, and unless otherwise stated, the terms have no special meaning, and thus should not be construed as limiting the scope of the present application. Furthermore, although terms used in the present application are selected from publicly known and commonly used terms, some terms mentioned in the specification of the present application may be selected by the applicant at his or her discretion, the detailed meanings of which are described in relevant parts of the description herein. Furthermore, it is required that the present application be understood, not simply by the actual terms used but by the meaning of each term lying within.

The wafer electroplating device is used for executing electroplating operation, spin-drying operation and flushing operation of the wafer. The wafer plating apparatus of the present application is improved in some respects, which are mainly related to spin-drying operation and rinsing operation.

Fig. 1 is a front view schematically showing a wafer plating apparatus when a spin-drying operation is performed, and fig. 2 is a front view schematically showing a wafer plating apparatus when a rinsing operation is performed. Referring to fig. 1 and 2, the wafer plating apparatus 010 includes a wafer holder 011, a plating chamber protection cap 012, a liquid reservoir 013, a water blocking ring 014, and a liquid sprayer 015. Wherein, the distance between the opening of the plating chamber protecting cover 012 and the plating liquid level in the liquid storage tank 013 along the vertical direction Y is a first height Hlc, the distance between the inner ring edge of the water retaining ring 014 and the plating liquid level in the liquid storage tank 013 along the vertical direction Y is a second height H2c, and the distance between the wafer clamp 011 and the plating liquid level in the liquid storage tank 013 along the vertical direction Y is a spin-drying height Hsc when the spin-drying operation is performed. In the embodiment shown in fig. 1, the second height H2c is 20mm and the spin height Hsc is 38-40mm. Obviously, the spin-drying height Hsc is greater than the second height H2c, so that, when the wafer electroplating device 010 performs a spin-drying operation, a part above the wafer clamp 011 is located above the horizontal plane where the inner ring edge of the water-blocking ring 014 is located. This results in the plating solution being thrown off the wafer and wafer clamp 011 entering the upper surface of water deflector ring 014 and the inner wall of plating chamber guard 012 above it, rather than returning to reservoir 013, and this thrown plating solution is subsequently collected for wastewater treatment, which on the one hand results in waste of plating solution and on the other hand also increases wastewater treatment costs.

Referring to fig. 2, the diameter of the opening of the plating chamber shield 012 is a first diameter D1c, and the distance between the wafer clamp 011 in the vertical direction Y and the plating liquid level in the liquid reservoir 013 at the time of the rinsing operation is a rinsing height Hcc. In the embodiment of fig. 2, the first height H1c is 180mm, the first diameter D1c is 460mm, and the rinse height Hcc is 110mm. The wafer holders with various sizes can be lifted in the plating chamber protecting cover 012 by designing the first diameter D1c with a relatively large diameter, but when the rinsing operation is performed, on one hand, the rinsing height Hcc should not be too high in order to avoid rinsing liquid and liquid thrown out from the wafer and the wafer holders to rush out of the plating chamber protecting cover 012; on the other hand, the flushing height Hcc should not be too low in order to reduce the amount of water to fall. In the wafer plating apparatus shown in fig. 1 and 2, the first diameter D1c of the opening of the plating chamber shield 012 is relatively large, and if the height of the wafer holder is raised in order to reduce the amount of water falling during the rinsing operation, water mist may be splashed from the opening; the first height H1c of the opening of the plating chamber shield 012 from the plating liquid surface is not high enough, so that the heights of the liquid sprayer 015, the water retaining ring 014, and the wafer clamp 011 cannot be further increased during the spin-drying operation and the rinsing operation, and the amount of the plating liquid to be thrown out and the amount of the plating liquid to be dropped into water cannot be improved.

Next, a wafer plating apparatus of the present application will be described by way of examples.

Fig. 3 is a front view of a wafer plating apparatus according to an embodiment of the present application during a plating operation, fig. 4 is a front view of a wafer plating apparatus according to an embodiment of the present application during a spin-drying operation, and fig. 5 is a front view of a wafer plating apparatus according to an embodiment of the present application during a rinsing operation. Fig. 6 is a schematic perspective view of a wafer plating apparatus according to an embodiment of the present application. Fig. 3-5 are schematic diagrams of the wafer plating apparatus 100 according to the same embodiment in different operation states, and therefore the same reference numerals are used for the same structures. Fig. 6 is used to more intuitively understand the structure of the wafer plating apparatus 100. The wafer plating apparatus 100 of the present application will now be described mainly with reference to fig. 3 to 6.

Referring to fig. 3, the wafer plating apparatus 100 includes a wafer chuck 110, a plating chamber shield 120, a reservoir 130, a water retaining ring 140, and a liquid sprayer 150. The wafer clamp 110 is disposed in the inner space S of the plating chamber protecting cover in a liftable manner along the vertical direction Y, the opening of the plating chamber protecting cover 120 has a first height H1 between the vertical direction Y and the plating liquid level SL, the inner diameter of the water retaining ring 140 has a second height H2 between the vertical direction Y and the plating liquid level SL, and the nozzle 151 of the liquid sprayer 150 has a third height H3 between the vertical direction Y and the plating liquid level SL. As shown in fig. 3, the third height H3 is greater than the second height H2, indicating that the sprayer 150 is positioned above the water barrier 140. A reservoir 130 is positioned at the bottom of the plating chamber shield 120, the reservoir 130 being operable to contain a plating solution. The water blocking ring 140 is disposed above the sump 130. A water deflector 140 and a liquid sprayer 150 are provided on the side wall of the plating chamber shield 120.

As shown in fig. 3, the plating chamber shield 120 is a case having an inner space S therein. The wafer holder 110 may drive a wafer (not shown) into contact with the plating solution in the reservoir 130 for plating operations. At this time, the lower surface of the wafer holder 110 and the wafer are immersed in the plating liquid. The vertical direction Y is shown in fig. 3. When the placement plane of the wafer plating apparatus 100 is a horizontal plane, the vertical direction Y is a direction perpendicular to the horizontal plane.

After the plating operation, the plating solution attached to the wafer and wafer holder 110 is further removed. Fig. 4 shows a state of the plating apparatus 100 when a spin-drying operation is performed, in which the wafer holder 110 drives the wafer to a spin-drying height Hs and rotates at a first speed to perform the spin-drying operation. The spin height Hs is less than the second height H2, that is, the upper surface 111 of the wafer holder 110 is located below the inner rim of the water stop ring 140. Referring to fig. 4, the spin height Hs refers to a distance between the level SL of the plating liquid and the upper surface of the wafer holder 110 projected in the vertical direction Y, that is, a minimum distance between the two in the vertical direction Y.

Compared with the wafer plating apparatus 010 shown in fig. 1 and 2, it is apparent that the wafer holder 110 is entirely located below the inner periphery of the water blocking ring 140, and the amount of the plating liquid thrown out during the spin-drying operation is reduced to some extent.

Referring to fig. 4, the wafer holder 110 is illustratively circular and has a certain thickness T1 in the vertical direction Y. In some embodiments, the thickness T1 is 30mm and the diameter of the top surface circle of the wafer holder 110 is 360mm, and the diameter of the top surface circle of the wafer holder 110 may be the same as or different from the diameter of the bottom surface circle. Wafers are loaded on the bottom surface of the wafer holder 110, and the wafer holder 110 may be a holder dedicated to holding wafers of a certain size, and in the semiconductor field, the wafer sizes are typically 6 inches, 8 inches, 12 inches, etc., and wafers of different sizes correspond to the wafer holders 110 of different sizes. Of course, the wafer holder 110 may also be a holder capable of holding wafers of different sizes. It will be appreciated that the thickness and diameter of the wafer holder 110 are not limited to the embodiments described above, and may be selected according to practical requirements.

When the spin-drying operation is performed, the distance between the lower surface of the wafer holder 110 and the liquid level SL of the plating solution is about 8-10mm.

In some embodiments, the second height H2 is in the range of 35-55mm, preferably 45mm. In the case that the spin-drying height Hs of the wafer chuck 110 is unchanged, in the wafer plating apparatus 100 of the embodiment shown in fig. 4, the height of the water blocking ring 140 is increased by about 25mm compared with the wafer plating apparatus 010 shown in fig. 1 and 2, so that almost all the plating solution that is spun out of the water blocking ring 140 can be blocked, the spin-out amount of the plating solution that is spun out to above the water blocking ring 140 is greatly reduced, the plating solution is saved, and the waste liquid treatment burden is reduced.

After the spin-drying operation, a rinsing operation is performed on the wafer and the wafer holder 110. Fig. 5 shows a state of the plating apparatus 100 when the flushing operation is performed. During the rinsing operation, the wafer holder 110 drives the wafer to a rinsing height Hc, which is greater than the spin-drying height Hs, the second height H2, and the third height H3, and rotates at the second speed to perform the rinsing operation. Referring to fig. 5, the rinse height Hc refers to a distance projected in the vertical direction Y between the lower surface of the wafer holder 110 and the liquid level SL of the plating liquid.

Referring to fig. 5, the sprayer 150 is used to spray cleaning liquid toward the wafer during a rinsing operation to clean the wafer. In some embodiments, the cleaning solution is deionized water. As shown in connection with FIG. 6, the spray 150 may be a spout.

In some embodiments, when the wafer chuck 110 drives the wafer to the rinse height Hc, the rotation speed of the wafer chuck 110 is reduced from the first rotation speed to the second rotation speed during the process of lifting the wafer chuck 110 in the Y direction, and when the wafer chuck reaches the rinse height Hc, the sprayer 150 sprays water to the wafer for rinsing. While rinsing, the wafer chuck 110 maintains a second speed, avoiding water accumulation on the wafer surface while maintaining a water film on the wafer surface. Most of the water sprayed from the sprayer 150 to the wafer should be thrown onto the water retaining ring 140 and then discharged through the water outlet.

As shown in fig. 5, the wafer holder 110 may be positioned above the plating chamber shield 120 in an initial state, and after loading the wafer, a controller (not shown) controls the wafer holder 110 to move downward in a vertical direction Y into the inner space S of the plating chamber shield 120. The plating chamber shield 120 has a top assembly 121 and a bottom assembly 122. The top assembly 121 and the bottom assembly 122 are connected to form the plating chamber shield 120. As shown in fig. 5, the top assembly 121 is a housing structure with a diameter gradually decreasing from bottom to top in the vertical direction, and the top of the top assembly 121 has an opening 121A, through which the wafer holder 110 enters and exits the plating chamber shield 120. The bottom assembly 122 is a cylindrical housing, and the parting line between the top assembly 121 and the bottom assembly 122 is shown as parting point 121B in FIG. 5. It is to be understood that the location of parting point 121B is not limited to that shown in FIG. 5 and may be moved upward or downward depending on the actual need, such as any location of parting point 121B between the opening 121A and the bottom of the plating chamber shield 120 at an upward H1/3 height. In some embodiments, the top assembly 121 and the bottom assembly 122 are removably coupled together such that the top assembly 121 may be quickly replaced for different sized wafer holders 110. The size of the opening 121A of different top assemblies 121 varies.

The connection between the top assembly 121 and the bottom assembly 122 is not limited, and the two may be illustratively connected by a detachable clip.

With continued reference to fig. 5, in an embodiment, the opening 121A of the plating chamber protecting cover 120 has a first diameter D1, the water retaining ring 140 has a first inner diameter R1, and a difference between the first inner diameter R1 and the first diameter D1 is greater than or equal to 0mm and less than or equal to 3mm. According to such a design, if water droplets are present at the opening 121A, they can fall on the water blocking ring 140 to be discharged or evaporated when they drop. In some embodiments, the first inner diameter R1 is equal to the first diameter D1, and is the limit size that ensures that the wafer holder 110 can be smoothly lifted in the water ring 140 and the hole of the opening 121A.

In some embodiments, the first diameter D1 ranges from 390-410mm, preferably the first diameter D1 is 400mm. When the wafer clamp is smaller in size, the electroplating cavity protection cover with the smaller first diameter D1 is preferably selected, and when the wafer clamp is larger in size, the electroplating cavity protection cover with the larger first diameter D1 is preferably selected, so that liquid can be prevented from being thrown out of the electroplating cavity protection cover. Compared to the wafer plating apparatus 010 shown in fig. 1 and 2, the first diameter D1 of the opening 121A of the wafer plating apparatus 100 is reduced by about 60mm, and compared to the wafer plating apparatus 010 having a larger opening in fig. 1 and 2, the opening size of the wafer plating apparatus 100 is smaller, which is helpful to avoid the liquid from throwing out of the plating chamber protecting cover.

Referring to fig. 5, the first height H1 is a distance between the opening 121A of the top member 121 and the liquid level SL of the plating liquid in the vertical direction Y. In some embodiments, the first height H1 ranges from 180-230mm, preferably 210mm. In some embodiments, top assembly 121 includes a shoulder 121C, with an opening height T2 between shoulder 121C and opening 121A. The wafer plating apparatus 010 of fig. 1 and 2 may have the same opening height T2 as compared to the wafer plating apparatus 100 of fig. 3-5, but the wafer plating apparatus 100 lifts the shoulder 121C of the plating chamber shield 120 to have a first height H1 greater than the first height H1C of the existing wafer plating apparatus 010, thereby increasing the overall height of the interior space of the plating shield 120. Referring to fig. 5, since the first height H1 is increased such that the height of the wafer holder 110 is also increased from the original when the rinsing operation is performed, the first height H1 is increased by 30mm, and the height of the wafer holder 110 is also increased by 30mm, for example, from the first height H1 c. In the embodiment with a removable top assembly 121, the first height H1 can be increased by simply replacing the top assembly 121 on an original basis.

The wafer plating apparatus 100 of the present application has a higher first height H1, so that the second height H2 corresponding to the water retaining ring 140 and the third height H3 corresponding to the liquid sprayer 150 are both improved compared to the existing apparatus.

In an embodiment, the third height H3 is in the range 45-65mm, preferably 55mm. Similar to the second height H2, the height of the nozzle 151 of the liquid sprayer 150 is also increased by about 25mm compared to the wafer plating apparatus 010 shown in fig. 1 and 2.

As shown in fig. 5 and 6, the water blocking ring 140 has a slope, i.e., the height of the inner rim 141 of the water blocking ring 140 in the vertical direction Y is higher than the height of the outer rim 142. Such that the water deflector 140 has a first angle θ with the horizontal in the range of 20 ° -40 °, preferably 30 °. Between the inner and outer rim 141, 142 is a first water blocking surface 143 of conical surface. The first water blocking surface 143 has opposite front and back surfaces, wherein the front surface refers to the surface of the water blocking ring 140 facing the opening. During the spin-drying operation, the plating liquid is blocked by the back surface of the water blocking ring 140 to flow back into the liquid reservoir, and during the rinsing operation, the rinse liquid is blocked by the front surface of the water blocking ring 140 to be drained into the drain. In the wafer plating apparatus 010 shown in fig. 1 and 2, the water blocking ring is generally disposed at an angle of 14 ° to the horizontal plane. In contrast, the water deflector 140 of the present application is more sloped, thereby providing better drainage on both the front and back sides, reducing edge drip of the inner diameter of the water deflector 140, and avoiding crystallization of plating solution along the wall at the back side.

In some embodiments, the angle of inclination of the water stop ring 140 is adjustable.

Referring to fig. 5, spray 150 has a second angle beta with the horizontal in the range of 16 deg. -30 deg., preferably 23 deg.. In the wafer plating apparatus 010 shown in fig. 1 and 2, the angle between the liquid sprayer and the horizontal plane is generally 14 ° and the angle between the water retaining ring and the horizontal plane is equal. In contrast, the sprayer 150 of the present application is also more inclined.

In some embodiments, the height of the nozzle 151 of the sprayer 150 is adjustable, and by adjusting the height of the nozzle 151 of the sprayer 150, the included angle between the fan-shaped cleaning liquid sprayed from the nozzle 151 and the wafer is a preset angle, which may be set according to practical requirements, for example, in an embodiment, the preset angle is 10 °, so that the radial velocity of the cleaning liquid is as large as possible on the premise of effectively flushing the wafer, which is beneficial to the purpose of reducing the water fall.

In some embodiments, the positions where the liquid sprayer 150 and the water blocking ring 140 are fixed on the inner wall of the plating chamber shield 120 are not changed compared to the wafer plating apparatus shown in fig. 1 and 2, and the height of the inner ring edge 141 of the water blocking ring 140 and the nozzle 151 is provided with a large adjustable space due to the high space of the inner space S of the wafer plating apparatus 100. It will be understood, of course, that the positions of the liquid jet 150 and the water retaining ring 140 in the present application may be fine-tuned as desired with respect to the wafer plating apparatus of fig. 1 and 2. In these embodiments, the connection members of the liquid sprayer 150 and the water blocking ring 140 to the inner wall of the plating chamber shield 120 need not be changed, and only the liquid sprayer 150 and the water blocking ring 140 need be replaced. In other embodiments, the liquid sprayer 150 and the water retaining ring 140 are fixedly connected to the plating chamber shield 120, and this can be achieved by replacing the plating chamber shield 120 when the positions of the liquid sprayer 150 and the water retaining ring 140 need to be adjusted.

In some embodiments, the position in which the liquid jet 150 and the water deflector 140 are secured to the inner wall of the plating chamber shield 120 is relatively increased as compared to the wafer plating apparatus shown in fig. 1 and 2.

In some embodiments, the liquid jet 150 has a predetermined length in the range of 77-97mm.

In some embodiments, the spray 150 passes through a sidewall of the plating chamber shield 120, and the spray nozzle 151 of the spray 150 is positioned in the interior space S of the plating chamber shield 120. According to this structure, the liquid sprayer 150 can be externally connected with a liquid storage device without additionally providing a liquid storage device in the plating chamber protecting cover 120.

In some embodiments, as shown in connection with fig. 6, the width of the water stop ring 140 (i.e., the first water stop surface 143) is in the range of 82-102mm, preferably 92mm. In the wafer plating apparatus 010 shown in fig. 1 and 2, the width of the water blocking ring is generally 82mm. In contrast, the width of the water retaining ring 140 of the present application is widened by about 10mm, and has a superior water retaining function. In combination with the change in the inclination angle of the water blocking ring 140, such a water blocking ring can improve the problems of inner diameter edge dripping and back plating solution crystallization.

3-5, compared with the wafer plating apparatus 010 shown in FIGS. 1 and 2, the wafer plating apparatus 100 of the present application has a higher first height H1, thereby having a higher inner space S, on the basis of which the second height H2 of the inner ring edge of the water retaining ring 140 and the third height H3 of the nozzle 151 of the liquid sprayer 150 are relatively increased, and during the spin-drying operation, the second height H2 is higher than the upper surface of the wafer clamp 110, thereby reducing the spin-drying amount of the plating liquid; meanwhile, during the rinsing operation, the reduced first diameter D1, the raised shoulder 121B and the raised third height H3 of the nozzle 151 combine to increase the height of the wafer holder 110 during the rinsing operation, for example, by 30mm, so that a lower water fall can be obtained while ensuring that no water mist is splashed.

The inventors of the present application obtained the following results through experiments:

the wafer electroplating device 010 shown in the figures 1 and 2 is adopted, the throwing amount of the electroplating solution is 4.5-5ml/pcs wafer, and the falling water amount is 110-120ml/min; with the wafer plating apparatus 100 shown in FIGS. 3 to 5 of the present application, the throwing amount of the plating solution is 0.1 to 0.2ml/pcs wafer, and the falling water amount is 80 to 90ml/min. It is apparent that the wafer plating apparatus 100 of the present application significantly reduces both the amount of plating solution that is thrown out and the amount of water that falls.

As previously described, wafers have different sizes and corresponding wafer holders have different sizes. However, the typical water retaining ring is fixedly disposed within the plating chamber shield, and is configured to accommodate a variety of different sized wafer clamps, with the water retaining ring aperture typically configured to accommodate the largest sized wafer clamp. As such, for small-sized wafer clamps, the aperture of the water retaining ring may be too large to effectively block rinse liquid from falling into the plating solution during rinsing. In some cases, different sizes of electroplating chambers are provided for wafer holders of different sizes, resulting in increased costs. In addition, in order to facilitate the ingress and egress of wafer clamps of different sizes into and out of the plating chamber shield, the opening of the plating chamber shield is typically sized to allow the largest sized wafer clamp to successfully ingress and egress into the plating chamber shield, which can result in cleaning fluid being easily spilled out of the plating chamber shield during a rinsing operation.

In some embodiments of the present application, the water deflector ring 140 is removably disposed within the plating chamber shield 120. In connection with the embodiment shown in FIG. 5, the top assembly 121 of the plating chamber shield 120 is a removable assembly. According to the embodiments, when the shift water ring 140 needs to be detached, the top assembly 121 is detached, so that the water retaining ring 140 with different sizes can be conveniently replaced, and the wafer clamp 110 with new sizes can be adapted by only changing the shift water ring 140 and the top assembly 121 without changing the basic structure of the electroplating chamber protecting cover 120.

In some embodiments, the size of the opening 121A of the top assembly 121 matches the size of the inner diameter of the removable water deflector ring 140.

In some embodiments, the opening 121A of the top assembly 121 is sized to be equal to the inner diameter of the removable water deflector ring 140. For example, for a 6 inch wafer chuck, the size of opening 121A of top assembly 121 and the inner diameter of removable water stop ring 140 are both B1; for an 8 inch wafer holder, the opening 121A of the top assembly 121 and the inner diameter of the removable water stop ring 140 are both sized B2, and so on.

In another aspect, the present application provides a cleaning method in a wafer plating process, which is performed using a wafer plating apparatus as described above. The cleaning method comprises the following steps:

step S21: the wafer clamp drives the wafer to reach the spin-drying height and rotates at a first speed to perform spin-drying operation.

Step S22: after the spin-drying operation is finished, the wafer clamp drives the wafer to reach a washing height and rotates at a second speed to carry out the washing operation, and the washing height is larger than the spin-drying height.

In addition, before the spin-drying operation, the wafer clamp can drive the wafer to enter the liquid storage tank to be in contact with the electroplating liquid in the liquid storage tank for electroplating operation. For details of the wafer cleaning method, reference is made to the foregoing description, and details are not repeated herein.

According to the wafer cleaning method, the spin-drying height is set to be smaller than the second height of the inner diameter of the water retaining ring, and when the wafer clamp drives the wafer to perform spin-drying operation after electroplating, the spin-drying amount of electroplating liquid is reduced. In addition, when the wafer clamp drives the wafer to carry out the flushing operation, the water falling quantity is reduced. Is beneficial to improving the service cycle of the electroplating solution.

While the basic concepts have been described above, it will be apparent to those skilled in the art that the above disclosure is by way of example only and is not intended to be limiting. Although not explicitly described herein, various modifications, improvements, and adaptations of the present application may occur to one skilled in the art. Such modifications, improvements, and modifications are intended to be suggested within this application, and are therefore within the spirit and scope of the exemplary embodiments of this application.

Meanwhile, the present application uses specific words to describe embodiments of the present application. Reference to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic is associated with at least one embodiment of the present application. Thus, it should be emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various positions in this specification are not necessarily referring to the same embodiment. Furthermore, certain features, structures, or characteristics of one or more embodiments of the present application may be combined as suitable.

Likewise, it should be noted that in order to simplify the presentation disclosed herein and thereby aid in understanding one or more inventive embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof. This method of disclosure, however, is not intended to imply that more features than are presented in the claims are required for the subject application. Indeed, less than all of the features of a single embodiment disclosed above.

In some embodiments, numbers describing the components, number of attributes are used, it being understood that such numbers being used in the description of embodiments are modified in some examples by the modifier "about," approximately, "or" substantially. Unless otherwise indicated, "about," "approximately," or "substantially" indicate that the number allows for a 20% variation. Accordingly, in some embodiments, numerical parameters set forth in the specification and claims are approximations that may vary depending upon the desired properties sought to be obtained by the individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and employ a method for preserving the general number of digits. Although the numerical ranges and parameters set forth herein are approximations that may be employed in some embodiments to confirm the breadth of the range, in particular embodiments, the setting of such numerical values is as precise as possible.

Claims (13)

1. The wafer electroplating device is characterized by comprising a wafer clamp, an electroplating cavity protective cover, a liquid storage tank, a water blocking ring and a liquid sprayer, wherein the wafer clamp is arranged in the inner space of the electroplating cavity protective cover in a lifting manner along the vertical direction, the wafer clamp is suitable for driving the wafer to reach a spin-drying height and rotating at a first speed to perform spin-drying operation, and driving the wafer to reach a flushing height and rotating at a second speed to perform flushing operation, and the flushing height is larger than the spin-drying height; the opening of the electroplating cavity protecting cover is provided with a first height along the vertical direction and between the electroplating liquid level; the liquid storage tank is positioned at the bottom of the electroplating cavity protective cover and is used for containing the electroplating liquid; the water retaining ring is arranged above the liquid storage tank, and a second height is arranged between the inner diameter of the water retaining ring and the liquid level of the electroplating liquid along the vertical direction, wherein the second height is larger than the spin-drying height, and the second height is smaller than the flushing height; the spray device is arranged on the side wall of the electroplating cavity protective cover, a third height is arranged between the spray nozzle of the spray device and the liquid level of the electroplating liquid along the vertical direction, the spray device is used for spraying cleaning liquid to the wafer to clean the wafer, the third height is larger than the second height, and the third height is smaller than the flushing height.

2. The wafer plating apparatus of claim 1, wherein the first height ranges from 180mm to 230mm.

3. The wafer plating apparatus of claim 1, wherein the opening of the plating chamber shield has a first diameter, the water retaining ring has a first inner diameter, and a difference between the first inner diameter and the first diameter is greater than or equal to 0mm and less than or equal to 3mm.

4. The wafer plating apparatus of claim 3, wherein said first diameter ranges from 390 mm to 410mm.

5. The wafer plating apparatus of claim 3, wherein said plating chamber shield has a removable top assembly.

6. The wafer plating apparatus of claim 1, wherein the second height is in the range of 35-55mm.

7. The wafer plating apparatus of claim 6, wherein said water deflector ring has a first angle with respect to the horizontal, said first angle ranging from 20 ° to 40 °.

8. The wafer plating apparatus of claim 7, wherein a width of said water retaining ring ranges from 82mm to 102mm.

9. The wafer plating apparatus of claim 1, wherein the third height is in the range of 45-65mm.

10. The wafer plating apparatus of claim 9, wherein said liquid jet has a predetermined length, said predetermined length ranging from 77 mm to 97mm.

11. The wafer plating apparatus of claim 10, wherein said liquid jet has a second angle with respect to the horizontal, said second angle ranging from 16 ° to 30 °.

12. The wafer plating apparatus of claim 1, wherein the first speed is greater than the second speed.

13. A cleaning method in a wafer plating process, wherein the method is performed using a wafer plating apparatus according to any of claims 1-12, comprising:

the wafer clamp drives the wafer to reach a spin-drying height and rotates at a first speed to perform spin-drying operation;

after the spin-drying operation is finished, the wafer clamp drives the wafer to reach a washing height and rotates at a second speed to perform the washing operation, and the washing height is larger than the spin-drying height.