Electroplating device and cleaning method

Abstract

Disclosed are an electroplating device and a cleaning method. The electroplating device comprises: a substrate holder comprising a holder main body, conductive contacts, and a sealing member, the bottom of the holder main body extending radially inward to form a substrate support portion, the sealing member being disposed on the surface of the substrate support portion and protruding upward at the end of the substrate support portion to form a sealing lip, and the sealing member and / or the holder main body having a groove on the radially outward side of the sealing lip for accommodating the conductive contacts; a cleaning system for injecting cleaning liquid into the groove to immerse and clean the conductive contacts; and a control system for controlling the substrate holder and the cleaning system to periodically perform immersion cleaning and spin-drying treatments on the conductive contacts, thereby improving the effect of cleaning the substrate holder.

Description

Electroplating device and cleaning method Technical Field

[0001] The present application relates to the field of semiconductor equipment, and further to an electroplating device and a cleaning method. Background Art

[0002] The substrate electroplating process refers to the process of electroplating metal ions in the plating solution onto the surface of the substrate to form metal interconnections during the chip manufacturing process.

[0003] In existing electroplating devices, the substrate clamp includes a conductive contact pin and a seal that contacts the substrate, wherein the conductive contact pin should evenly contact the seed layer on the front side of the substrate. At the same time, the conductive contact pin cannot directly contact the electroplating solution. Therefore, a seal is needed to isolate the substrate so that the electroplating solution cannot reach the edge of the front side of the substrate. Otherwise, the edge of the front side of the substrate will be plated with metal, and the uniformity of the metal film deposited on the substrate will deteriorate. After the electroplating is completed, there will often be residues on the conductive contact pin and the seal, such as residual electroplating solution and even photoresist. This residue will affect the process of the substrate, such as causing uneven electric field distribution on the substrate, failure of the substrate seal, and failure of the substrate to be taken out when the robot transfers the substrate after electroplating.

[0004] The document with patent application number 201911077619.1 provides an electroplating device and a cleaning method, which provides an electroplating liquid storage tank with a middle section of a cleaning tube in contact with the electroplating liquid, and uses the electroplating liquid with a preset temperature to heat the middle section of the cleaning tube to obtain a heated cleaning liquid, and then uses the electroplating liquid with a preset temperature to heat the cleaning liquid for spray cleaning of the substrate fixture to remove residues. Summary of the Invention

[0005] In response to the above technical problems, the purpose of this application is to improve the cleaning effect of the substrate clamp of the electroplating device.

[0006] In order to achieve the above objectives, the present application provides an electroplating device and a cleaning method.

[0007] In some embodiments, the electroplating device includes: a substrate clamp, including a clamp body, a conductive contact and a seal, the bottom of the clamp body extends radially inward to form a substrate support portion, the seal is arranged on the surface of the substrate support portion, and protrudes upward at the end of the substrate support portion to form a sealing lip, the seal and / or the clamp body has a groove for accommodating the conductive contact on the radially outward side of the sealing lip; a cleaning system for injecting cleaning liquid into the groove to soak and clean the conductive contact; a control system for controlling the substrate clamp and the cleaning system to periodically soak and clean and spin-dry the conductive contact.

[0008] In some embodiments, the cleaning method comprises:

[0009] Step S01: raising and lowering the unloaded substrate clamp to a preset height so that the substrate clamp is higher than the nozzle of the cleaning system; Step S02: rotating the substrate clamp at a first speed, and the nozzle spraying cleaning liquid into the groove at a preset flow rate for a first preset time to soak and clean the conductive contact, and the nozzle stops spraying cleaning liquid before the volume of the cleaning liquid injected into the groove exceeds the maximum water storage capacity of the groove; Step S03: rotating the substrate clamp at a second speed for a second preset time, the second speed being greater than the first speed, to dry the cleaning liquid in the groove.

[0010] Compared with the prior art solution of using a nozzle to spray clean the substrate clamp, the present application performs periodic immersion cleaning and spin-drying treatment on the conductive contacts, so that the contact between the cleaning liquid and the conductive contacts is more complete, and it is easier to remove residues on the surface of the conductive contacts, thereby increasing the cleaning effect of the substrate clamp.

[0011] Summary of the Figures

[0012] The features and performance of the present application are further described by the following examples and accompanying drawings. The preferred embodiments will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above characteristics, technical features, advantages and implementation methods of the present invention.

[0013] FIG1 is a schematic diagram of an electroplating device according to an embodiment of the present application;

[0014] FIG2 a is a partial enlarged view of area a in FIG1 according to one embodiment of the present application;

[0015] FIG2 b is a partial enlarged view of area a in FIG1 according to another embodiment of the present application;

[0016] FIG3 is a schematic diagram of an electroplating device according to an embodiment of the present application;

[0017] FIG4 is a partial enlarged view of area b in FIG3 ;

[0018] FIG5 is a schematic diagram of the cleaning liquid in the groove shown in FIG2a under the maximum water storage state;

[0019] FIG6 is a step diagram of a cleaning method according to an embodiment of the present application.

[0020] Preferred embodiment of this application

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings and other embodiments can be obtained based on these drawings without inventive work.

[0022] To simplify the drawings, only portions relevant to the invention are schematically depicted in each figure; they do not represent the actual structure of the product. Furthermore, to simplify the drawings and facilitate understanding, in some figures, only one component with the same structure or function is schematically depicted or labeled. In this document, "one" not only means "only one" but also "more than one."

[0023] It should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0024] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0025] As shown in FIG. 1 and FIG. 2 a , an electroplating device 100 according to an embodiment of the present application is disclosed, including a substrate clamp 120 , a cleaning system 130 and a control system 140 .

[0026] The substrate clamp 120 includes a clamp body 121, a conductive contact 122, and a seal 123. The bottom of the clamp body 121 extends radially inward to form a substrate support portion 1211. The seal 123 is disposed on the surface of the substrate support portion 1211 and protrudes upward from the end of the substrate support portion 1211 to form a sealing lip 1231. The seal 123 and / or the clamp body 121 has a groove 1232 on the radially outward side of the sealing lip 1231 for accommodating the conductive contact 122. The cleaning system 130 is used to inject cleaning liquid into the groove 1232 to soak and clean the conductive contact 122. The control system 140 is used to control the substrate clamp 120 and the cleaning system 130 to periodically soak and clean the conductive contact 122 and spin-dry it. It should be noted that the clamp body 121 is typically shaped to match the substrate 200. For example, if the substrate 200 is circular, the clamp body 121 is annular. Therefore, the term "radial" in the foregoing text should be understood as referring to the direction from a certain position on the clamp body toward its centerline. Furthermore, the term "end" of the substrate support portion 1211 in the foregoing text refers to the end of the substrate support portion 1211 closest to the centerline of the clamp body 121.

[0027] Specifically, the substrate clamp 120 further includes an inner pressure ring 126 and an outer pressure ring 127. The inner pressure ring 126 is locked to the inner circumference 1212 of the clamp body 121, while the outer pressure ring 127 is locked to the outer circumference 1213 of the clamp body 121. The seal 123 includes an inner end 1233, a seal body 1234, and an outer end 1235. The outer end 1235 is fixed between the outer pressure ring 127 and the clamp body 121, while the inner end 1233 is fixed between the inner pressure ring 126 and the clamp body 121. The seal body 1234 covers the upper surface, inner circumference, and lower surface of the substrate support portion 1211. The sealing lip 1231 is formed on the upper surface of the seal body 1234 and is higher than the upper surface of the seal body 1234. This forms a groove 1232 on the upper surface of the seal body 1234 between the radially outward side of the sealing lip 1231 and the inner pressure ring 126. That is, the groove 1232 is located on the upper surface of the seal body 1234. Furthermore, one end 1221 of the conductive contact 122 is fixed between the inner end 1233 of the seal 123 and the inner pressure ring 126, while the other end 1222 of the conductive contact 122 extends along the surface of the seal body 1234 into the groove 1232.

[0028] As shown in FIG2b , in another embodiment of the present application, the substrate clamp 120 includes an inner pressure ring 129, which is locked to the inner circumferential surface 1212 of the clamp body 121. The distal end of the substrate support portion 1211 protrudes upward, and the protruding portion 1214 is covered by the sealing member 123 to form a sealing lip 1231. A groove 1232 is formed on the upper surface of the substrate support portion 1211 between the radially outward side of the sealing lip 1231 and the inner pressure ring 129. The radially outward side of the sealing lip 1231 on the upper surface of the substrate support portion 1211 is not covered by the sealing member 123, i.e., the groove 1232 is located on the upper surface of the substrate support portion 1211. Furthermore, one end 1221 of the conductive contact 122 is fixed between the substrate support portion 1211 and the inner pressure ring 126, while the other end 1222 of the conductive contact 122 extends along the surface of the substrate support portion 1211 into the groove 1232.

[0029] In actual application, when the substrate clamp 120 is in an unloaded state, as shown in Figures 1, 2a and 2b, the end 1222 of the conductive contact 122 away from the inner pressure ring 126 has a rebound height greater than the sealing lip 1231; when the substrate clamp 120 is in a state loaded with a substrate 200, as shown in Figures 3 and 4, the substrate 200 is clamped between the pressure plate 128 and the substrate support portion 1211, and the end 1222 of the conductive contact 122 away from the inner pressure ring 126 is deformed under the pressure of the edge of the substrate 200, so that the conductive contact 122 is in full electrical contact with the substrate 200 until the edge of the substrate 200 is in sealing contact with the sealing lip 1231, so that the conductive contact 122 is isolated from the plating liquid in the process chamber 110.

[0030] Preferably, the cleaning system 130 includes a nozzle 131 configured to spray cleaning liquid into the groove 1232. During immersion cleaning, the control system 140 controls the substrate holder 120 to rotate at a first speed, and the nozzle 131 sprays cleaning liquid into the groove 1232 at a preset flow rate for a first preset duration, with the cleaning liquid injected into the groove 1232 not exceeding the maximum water storage capacity of the groove 1232. During the spin-drying process, the control system 140 controls the nozzle 131 to stop spraying cleaning liquid, and the substrate holder 120 rotates at a second speed for a second preset duration, the second speed being greater than the first speed, to spin-dry the cleaning liquid in the groove 1232. Furthermore, the cleaning system 130 also includes a cleaning liquid storage tank 132, which is connected to the nozzle 131 via a pipe 133 for supplying cleaning liquid to the nozzle 131.

[0031] Preferably, the nozzle 131 is configured to have an upwardly tilted spray direction, and the fixture body 121 is located above the nozzle 131 during immersion cleaning. In actual application, a fixture bracket 124 (see Figure 1) is provided above the fixture body 121 to connect the fixture body 121 to the drive device 125. If the nozzle 131 is configured to have a downwardly tilted spray direction, the fixture body 121 needs to be moved below the nozzle 131 during immersion cleaning. The fixture bracket 124 will block the spray path of the nozzle 131, causing the cleaning liquid to be sprayed onto the surface of the fixture bracket 124, reducing cleaning efficiency, and there is a risk of dripping into the process chamber 110 and contaminating the electroplating solution.

[0032] Specifically, referring again to FIG. 2 a , during immersion cleaning, nozzle 131 sprays cleaning liquid along spray path s onto the inner wall of inner pressure ring 126 . The cleaning liquid then flows from the inner wall of inner pressure ring 126 along conductive contact 122 into groove 1232 , until the other end 1222 of conductive contact 122 is immersed in the cleaning liquid. It should be noted that due to the surface tension of the cleaning liquid, in some cases, the liquid level in groove 1232 may slightly rise above the top of groove 1232 , allowing the other end 1222 of conductive contact 122 to be submerged.

[0033] Preferably, as shown in FIG. 3 , the electroplating device 100 further includes a process chamber 110 .

[0034] Specifically, the process chamber 110 includes an inner cavity 111, an overflow trough 112, and a protective cover 113. The inner cavity 111 is used to store the plating solution and has an opening 1111. The substrate holder 120 moves into and out of the inner cavity 111 through the opening 1111. The overflow trough 112 is constructed around the periphery of the opening 1111 to collect the plating solution that overflows from the inner cavity 111. The protective cover 113 is constructed around the overflow trough 112 to block the cleaning solution spun out of the substrate holder 120 during the spin-drying process. The nozzle 131 is constructed on the inner sidewall 1131 of the protective cover 113.

[0035] Preferably, an annular collecting groove 1132 is configured on the inner sidewall 1131. The annular collecting groove 1132 is used to collect the cleaning liquid spun out by the substrate holder 120 during the spin-drying process. The nozzle 131 is configured within the annular collecting groove 1132. In this embodiment, the annular collecting groove 1132 can collect both the cleaning liquid spun out by the substrate holder 120 during the spin-drying process and the cleaning liquid remaining on the nozzle 131, thereby reducing the risk of contamination of the electroplating solution in the process chamber 110.

[0036] Preferably, at least two nozzles 131 are provided on the inner sidewall 1131 of the protective cover 113, and the at least two nozzles 131 are spaced apart and arranged on the same circumference. In this embodiment, increasing the number of nozzles 131 can increase the speed at which the cleaning liquid is injected into the groove 1232, thereby reducing the first preset duration of spraying the cleaning liquid into the groove 1232 and improving the cleaning efficiency of the equipment.

[0037] Preferably, the first rotational speed is configured such that, when the substrate clamp 120 rotates at the first rotational speed, the nozzle 131 sprays the cleaning liquid at a preset flow rate into the groove 1232 for a first preset time period, and the substrate clamp 120 does not swing out the cleaning liquid; the second rotational speed is configured such that, when the substrate clamp 120 rotates at the second rotational speed, the substrate clamp 120 swings out the cleaning liquid.

[0038] Preferably, the above-mentioned first speed is 100r / min to 150r / min, the above-mentioned first preset time is 3s to 4s, and the preset flow rate is 150ml / min to 200ml / min; the above-mentioned second speed is 300r / min to 400r / min, and the above-mentioned second preset time is 4s to 5s.

[0039] Specifically, in order to avoid excessive cleaning liquid being injected into the groove 1232, causing the cleaning liquid to overflow the groove 1232 and drip into the inner cavity 111, thereby contaminating the electroplating solution, the first preset time length T1, the preset flow rate Q and the maximum water storage capacity V max Should satisfy: T1*Q≤V max .

[0040] In addition, the groove 1232 is annular in structure, and the bottom surface of the groove 1232 is annular. When the volume of the cleaning liquid injected into the groove 1232 is close to the maximum water storage capacity V of the groove 1232, max 5, the cross section of the cleaning liquid retained in the groove 1232 is approximately triangular 1321. If the center line of the substrate fixture 120 is taken as the Y axis and the straight line 1322 of the substrate fixture 120 passing through the bottom surface of the groove 1232 is taken as the X axis to establish a two-dimensional coordinate system, that is, the maximum water storage capacity V max is approximately equal to the volume of triangle 1321 rotated around the Y axis. In addition, assuming that the coordinates of the three vertices of triangle 1321 are (m, 0), (n, 0) and (n, h), then:

[0041] V max =(πn 2 *h-πm 2 *h) / 2=π(n 2 -m 2 )*h / 2; where

[0042] m: inner radius of the bottom surface of the groove;

[0043] n: outer radius of the bottom surface of the groove;

[0044] h: the height of the conductive contact from the bottom surface of the groove.

[0045] If the measured data is m=148mm, n=153mm, h=5mm;

[0046] Substituting into the above formula we can get V max ≈11.820ml;

[0047] When T1*Q≤V max Under the premise of multiple tests, the optimal value of the first preset time length T1 is 3.5s, and the optimal value of the preset flow rate Q is 180ml / min.

[0048] Furthermore, experiments based on a preset flow rate Q = 180 ml / min revealed that a first rotational speed of 150 r / min provided the most stable injection of cleaning liquid into groove 1232. If the first rotational speed is too high, the cleaning liquid will be subjected to a greater centrifugal force, causing it to be thrown out of groove 1232. If the first rotational speed is too low, too much cleaning liquid will be injected into the same area of ​​groove 1232, causing it to overflow from groove 1232.

[0049] In addition, based on V max ≈11.820ml was tested, and it was found that when the second speed was 400r / min and the first preset time T1 was 4s, all the cleaning liquid in the groove 1232 could be thrown out.

[0050] As shown in FIG6 , a cleaning method according to an embodiment of the present application is disclosed. The method is applicable to the electroplating apparatus 100 of any of the above embodiments, comprising:

[0051] Step S01: lifting the unloaded substrate holder 120 to a predetermined height so that the substrate holder 120 is higher than the nozzle 131 of the cleaning system 130;

[0052] Step S02: The substrate holder 120 rotates at a first rotational speed, and the nozzle 131 sprays a cleaning liquid at a preset flow rate into the groove 1232 for a first preset time period to soak and clean the conductive contact 122. The nozzle 131 stops spraying the cleaning liquid before the volume of the cleaning liquid injected into the groove 1232 exceeds the maximum water storage capacity of the groove 1232.

[0053] In step S03 , the substrate clamp 120 rotates at a second rotation speed for a second predetermined time period, where the second rotation speed is greater than the first rotation speed, so as to dry out the cleaning liquid in the groove 1232 .

[0054] Wherein, step S02 and step S03 are repeated at least once to complete the cleaning of the conductive contacts.

[0055] In this embodiment, the conductive contacts 122 are periodically immersed, cleaned, and dried, so that the cleaning liquid comes into more complete contact with the conductive contacts 122 , making it easier to remove residues on the surfaces of the conductive contacts 122 , thereby improving the cleaning effect of the substrate fixture 120 .

[0056] It should be noted that the above embodiments can be freely combined as needed. The above are only preferred embodiments of the present invention. For those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be considered as the scope of protection of the present invention.

Claims

1. An electroplating device, characterized in that, include: A substrate clamp, comprising a clamp body, a conductive contact and a sealing member, wherein the bottom of the clamp body extends radially inward to form a substrate supporting portion, the sealing member is arranged on the surface of the substrate supporting portion and protrudes upward at the end of the substrate supporting portion to form a sealing lip, and the sealing member and / or the clamp body has a groove for accommodating the conductive contact on one side of the sealing lip along the radial outward direction; A cleaning system, used for injecting cleaning liquid into the groove to soak and clean the conductive contact; The control system is used to control the substrate fixture and the cleaning system to periodically perform immersion cleaning and spin-drying treatment on the conductive contacts.

2. The electroplating apparatus according to claim 1, wherein The cleaning system comprises: A nozzle, wherein the nozzle is configured to spray the cleaning liquid into the groove; wherein, During the immersion cleaning, the control system controls the substrate clamp to rotate at a first speed, the nozzle sprays the cleaning liquid into the groove at a preset flow rate for a first preset time, and the cleaning liquid injected into the groove does not exceed the maximum water storage capacity of the groove; During the spin-drying process, the control system controls the nozzle to stop spraying the cleaning liquid, and the substrate clamp rotates at a second speed for a second preset time period, the second speed being greater than the first speed, to spin-dry the cleaning liquid in the groove.

3. The electroplating device according to claim 2, characterized in that: The maximum water storage capacity V max =(πn 2 *h - πm 2 *h) / 2; in, m: the inner radius of the bottom surface of the groove; n: the outer radius of the bottom surface of the groove; h: the height of the conductive contact from the bottom surface of the groove.

4. The electroplating device according to claim 2, characterized in that: The nozzle is configured to have a spray direction that is inclined upward, and the jig body is located above the nozzle during the immersion cleaning.

5. The electroplating apparatus according to claim 2, characterized in that, Also included is a process chamber, the process chamber comprising: An inner cavity, the inner cavity is used to store the electroplating solution, the inner cavity has an opening, and the substrate fixture moves into or out of the inner cavity through the opening; An overflow trough, surroundingly constructed at the periphery of the opening, for collecting the electroplating liquid overflowing from the inner cavity; A protective cover is constructed around the overflow tank and is used to block the cleaning liquid thrown out by the substrate clamp during the spin-drying process, wherein the nozzle is constructed on the inner side wall of the protective cover.

6. The electroplating device according to claim 5, characterized in that: The inner side wall is configured with an annular collecting groove, and the annular collecting groove is used to collect the cleaning liquid spun out by the substrate clamp during the spin-drying process, wherein the nozzle is configured in the annular collecting groove.

7. The electroplating device according to claim 5, characterized in that: The inner side wall of the protective cover is provided with at least two nozzles, and the at least two nozzles are arranged at intervals on the same circumference.

8. The electroplating device according to claim 2, characterized in that: The first rotation speed is configured such that, when the substrate clamp rotates at the first rotation speed, if the nozzle sprays the cleaning liquid at a preset flow rate to the groove for a first preset time, the substrate clamp does not throw out the cleaning liquid; The second rotation speed is configured such that during the rotation of the substrate fixture at the second rotation speed, the substrate fixture flings out the cleaning liquid.

9. The electroplating apparatus according to claim 8, wherein: The first rotation speed is 100 r / min to 150 r / min, the first preset duration is 3 s to 4 s, and the preset flow rate is 150 ml / min to 200 ml / min; The second rotation speed is 300 r / min to 400 r / min, and the second preset duration is 4 s to 5 s.

10. A cleaning method, characterized in that, Applicable to the electroplating apparatus according to any one of claims 1-9, comprising: Step S01: Lift the empty substrate fixture to a preset height so that the substrate fixture is higher than the nozzle of the cleaning system; Step S02: Rotate the substrate fixture at the first rotation speed, and the nozzle sprays the cleaning liquid into the groove for a first preset duration at a preset flow rate to soak and clean the conductive contact, and before the volume of the cleaning liquid injected into the groove exceeds the maximum water storage capacity of the groove, the nozzle stops spraying the cleaning liquid; Step S03: The substrate fixture rotates at the second rotation speed for a second preset duration, and the second rotation speed is greater than the first rotation speed to spin-dry the cleaning liquid in the groove; Wherein, the steps S02 and S03 are repeatedly executed at least once to complete the cleaning of the conductive contact.

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