Electroplating apparatus and electroplating method

Abstract

The present invention provides an electroplating device and an electroplating method. The electroplating device at least includes: an electroplating chamber for containing electroplating solution, the interior of the electroplating chamber is divided into an anode chamber and a cathode chamber by a partition component, and an anode is accommodated in the anode chamber; a substrate holder, the substrate holder includes a first driver and a substrate clamp, the substrate clamp is used to hold the substrate, and the first driver is used to drive the substrate clamp to move up and down so that the process position of the substrate maintains a predetermined gap from the partition component; wherein, the anode is a consumable anode, and the partition component is configured to be movable relative to the anode to maintain a constant distance between the partition component and the anode. The electroplating device and the electroplating method of the present invention maintain the relative position between the anode and the substrate unchanged through the mobility of the partition component and the substrate, and improve the electroplating uniformity.

Description

Technical Field

[0001] The present invention relates to the field of electroplating equipment, and in particular to an electroplating device and an electroplating method. Background Art

[0002] With the increasingly reduced feature size of semiconductor devices, the current semiconductor industry has an ever-increasing demand for copper interconnect processes. Copper electrochemcial deposition (copper electroplating) has advantages such as economy, selectivity, excellent throwing power, suitability for mass production, and good resistance to metal and organic impurities, making it the preferred method for copper interconnect filling at present. Before the copper electroplating process, a barrier layer (such as tantalum nitride, etc.) is first deposited on a silicon wafer, and a copper seed layer is sputtered thereon, which is used as a bottom layer for copper electroplating.

[0003] An electroplating device generally consists of an electroplating chamber and a substrate holding device. The electroplating chamber is used to accommodate electroplating solution, and is usually divided into an anode chamber and a cathode chamber by a separation component that allows specific ions (metal ions to be plated) to pass through freely. An anode target (usually a copper block) is provided in the anode chamber; the substrate holding device (see the published patent, application number: CN201580085077.6) is used to drive the wafer to be immersed in the electroplating solution in the cathode chamber during the electroplating process. When a power supply is loaded between the copper block (the copper block serves as the anode) and the substrate (the substrate serves as the cathode), an electric current is generated in the electroplating solution and an electric field is formed between the anode and the cathode. The anode reacts to convert into copper ions and electrons, and the copper ions near the cathode combine with the electrons to form a copper layer deposited on the surface of the substrate. Among them, the anode target is a consumable anode, and its height gradually thins as the number of substrates electroplated increases, thereby causing the distance between it and the cathode to continuously increase, which will affect the electric field distribution inside the electroplating chamber, and thus deteriorate the uniformity of substrate electroplating.

[0004] Therefore, it is necessary to provide an electroplating device and an electroplating method to improve the electroplating uniformity. Summary of the Invention

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide an electroplating device and an electroplating method to improve the uniformity of the electric field distribution inside the electroplating chamber and the uniformity of substrate electroplating.

[0006] To achieve the above purpose and other related purposes, the present invention provides an electroplating device, at least including:

[0007] An electroplating chamber for accommodating electroplating solution, the interior of the electroplating chamber is divided into an anode chamber and a cathode chamber by a separation component, and an anode is accommodated in the anode chamber;

[0008] A substrate holder, the substrate holder includes a first driver and a substrate clamp, the substrate clamp is used to hold the substrate, and the first driver is used to drive the substrate clamp to move up and down so that a predetermined gap is maintained between the process position of the substrate and the separation component;

[0009] Wherein, the anode is a consumable anode, and the separation component is configured to be movable relative to the anode to maintain a constant distance between the separation component and the anode.

[0010] Optionally, the anode chamber includes:

[0011] A telescopic side wall, the separation component is installed on the top of the telescopic side wall;

[0012] A driving mechanism, the driving mechanism is used to drive the telescopic side wall to move up and down so that the distance between the separation component and the anode is constant.

[0013] Optionally, the driving mechanism includes:

[0014] A sliding component, the sliding component includes a vertically installed slide rail and a slider moving on the slide rail, and the slider is fixedly connected to the telescopic side wall;

[0015] An elastic member, the elastic member is used to elastically support the slider;

[0016] A top push rod, the top push rod is connected to the first driver. When the first driver drives the top push rod to move down, the top push rod pushes the slider to move down synchronously, and at the same time drives the separation component to descend. When the first driver drives the top push rod to return to the initial position, the separation component is reset under the action of the elastic member.

[0017] Optionally, the driving mechanism includes:

[0018] A sliding component, the sliding component includes a vertically installed slide rail and a slider moving on the slide rail, and the slider is fixedly connected to the telescopic side wall;

[0019] A second driver, the second driver drives the slider to drive the telescopic side wall to move up and down.

[0020] Optionally, the separation component includes an ion membrane skeleton, and the ion membrane skeleton is fixedly installed on the top of the anode chamber.

[0021] Optionally, the separation component further includes a diffusion plate, and the diffusion plate is fixedly installed on the ion membrane skeleton.

[0022] Optionally, the electroplating device further includes an anode height detector, which is used to collect the height information of the anode target to determine the compensation displacement of the separation component or the substrate holder.

[0023] The present invention also provides an electroplating method, which includes the steps of:

[0024] Obtaining the reduction amount of the anode height;

[0025] Calculating the compensation displacement amounts required for the substrate holder and the separation component according to the reduction amount, and controlling the movement of the substrate holder and the separation component so that the process position of the substrate maintains a predetermined gap with the separation component, and the distance between the separation component and the anode is constant;

[0026] Electroplating the substrate.

[0027] Optionally, the method for obtaining the reduction amount of the anode height includes collecting the height information of the anode through an anode height detector, comparing it with the original height of the anode, and calculating the reduction amount of the anode height.

[0028] Optionally, the substrate holder and the separation component move simultaneously based on the displacement compensation amount.

[0029] Optionally, after the separation component performs compensation displacement based on the displacement compensation amount, the substrate holder moves downward so that the process position of the substrate maintains a predetermined gap with the separation component.

[0030] As described above, the electroplating device and the electroplating method provided by the present invention have the following beneficial effects:

[0031] Through the telescopic design of the anode chamber, the separation component can move to keep the distance between the substrate and the anode fixed;

[0032] By adding an anode height detector to collect the anode height information, the consumed height of the anode is automatically compensated to keep the distance between the substrate and the anode fixed;

[0033] Through the linkage design of the substrate holder and the telescopic anode chamber, while adjusting the position of the substrate, the positions of the ion membrane and the diffusion plate are also adjusted, which can ensure the consistency of the positions of the substrate, the diffusion plate, the ion membrane skeleton and the anode target during electroplating, and can greatly improve the uniformity of the electric field distribution in the electroplating chamber after the consumption of the anode target and the uniformity of the electroplated product. Description of the Drawings

[0034] Figure 1 It shows a schematic structural diagram of the electroplating device provided in Embodiment 1.

[0035] Figure 2 It shows a position relationship diagram of each component of the electroplating device provided in Embodiment 1 at the initial position.

[0036] Figure 3It shows the positional relationship diagram of each component of the electroplating device provided in the first embodiment when it is in the electroplating process position.

[0037] Figure 4 It shows the structural schematic diagram of the electroplating device provided in the second embodiment.

[0038] Element number description

[0039] 11 Electroplating tank

[0040] 111 Anode chamber

[0041] 112 Cathode chamber

[0042] 1111 Retractable side wall

[0043] 1112 Anode

[0044] 1113 Slide block

[0045] 1114 Slide rail

[0046] 1115 Elastic component

[0047] 1116 Top push rod

[0048] 12 Separation component

[0049] 121 Ion membrane skeleton

[0050] 122 Diffusion plate

[0051] 13 Substrate holder

[0052] 131 Substrate clamp

[0053] 132 First driver

[0054] 14 Anode height detector

[0055] 15 Substrate

[0056] 21 Electroplating tank

[0057] 211 Anode chamber

[0058] 212 Cathode chamber

[0059] 2111 Retractable side wall

[0060] 2112 Anode

[0061] 2113 Slide block

[0062] 2114 Slide rail

[0063] 2115 Second driver

[0064] 22 Separation component

[0065] 221 Ion exchange membrane skeleton

[0066] 222 Diffusion plate

[0067] 23 Substrate holder

[0068] 231 Substrate clamp

[0069] 232 First driver

[0070] 24 Anode height detector

[0071] 25 Substrate

[0072] A Initial position of the substrate clamp

[0073] A' Electroplating process position of the substrate clamp

[0074] B Initial position of the separation component

[0075] B' Electroplating process position of the separation component

[0076] d1 Distance between the substrate and the anode

[0077] d2 Distance between the separation component and the anode

[0078] d3 Distance between the substrate and the separation component

[0079] h Original height of the anode

[0080] h1 Anode height reduction Detailed implementation manners

[0081] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0082] Please refer to Figures 1 to 4 . It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0083] Such as Figure 1As shown in the figure, the present invention provides an electroplating device, which includes an electroplating chamber 11 for containing electroplating solution. The interior of the electroplating chamber 11 is divided into an anode chamber 111 and a cathode chamber 112 by a partition component 12. An anode 1112 is accommodated in the anode chamber 111; a substrate holder 13, which includes a first driver 132 and a substrate clamp 131. The substrate clamp 131 is used to hold the substrate 15, and the first driver 132 is used to drive the substrate clamp 13 up and down so that the process position of the substrate 15 maintains a predetermined gap from the partition component 12; wherein, the anode 1112 is a consumable anode, and the partition component 12 is configured to be movable relative to the anode 1112 to maintain a constant distance between the partition component 12 and the anode 1112.

[0084] As an example, as Figure 1 shown, the anode chamber 111 includes: a telescopic side wall 1111, and the partition component 12 is installed at the top of the telescopic side wall 1111; a driving mechanism for driving the partition component 12 to move so as to maintain a constant distance between the partition component 12 and the anode 1112. The telescopic side wall 1111 is corrugated or of other shapes, and its material can be selected from PTEE material or other applicable materials, which is not limited here. In this embodiment, the side wall of the anode chamber is designed to be telescopic, so as to meet the up and down movement of the partition component, and finally realize a constant distance between the partition component 12 and the anode 1112. In conventional electroplating equipment, the partition component is located between the anode chamber and the cathode chamber, and its position in the electroplating chamber is fixed. When the anode is continuously consumed during the operation of the equipment, due to the obstruction of the partition component, the substrate holder loaded with the substrate cannot continuously move towards the anode to maintain a constant distance between the substrate and the anode, and the change in the distance between the substrate and the anode will affect the electric field distribution and intensity in the electroplating chamber, resulting in problems such as poor uniformity of the electroplated substrate. For the above reasons, this embodiment adopts a telescopic anode chamber design to meet the need for the downward movement of the substrate holder 13.

[0085] Specifically, the driving mechanism includes a sliding component, which includes a vertically installed slide rail 1114 and a slider 1113 moving on the slide rail. The slider 1113 is fixedly connected to the telescopic side wall 1111; an elastic member 1115 for elastically supporting the slider 1113; a top push rod 11116 connected to the first driver 132. When the first driver 132 drives the top push rod 1116 to move downward, the top push rod 1116 will also drive the slider 1113 to move downward synchronously, so that the partition component 12 descends. When the first driver 132 drives the substrate holder 13 to move to the initial position, the telescopic side wall 1111 is reset under the action of the elastic member 1115. In this embodiment, the elastic member 1115 is a spring. In other embodiments, other elastic members can also be selected as long as they can achieve elastic support.

[0086] As an example, asFigure 1 As shown in the figure, the electroplating apparatus provided in this embodiment further includes an anode height detector 14. The anode height detector 14 can be an ultrasonic displacement detector or other detectors that can detect anode height information. Through the anode height detector 14, the anode height information can be collected in a non-contact manner, and the reduction amount of the anode height can be grasped in real time. In other embodiments, the reduction amount of the anode height can also be calculated by other methods, such as through the calculation of process parameters and process time, etc. The method for obtaining the reduction amount of the anode height is not limited here.

[0087] As an example, as Figure 1 shown in the figure, the separation component 12 includes an ion membrane skeleton 121 and / or a diffusion plate 122. The ion membrane skeleton 121 is fixed on the top of the anode chamber 111. Preferably, the diffusion plate 122 is fixed on the ion membrane skeleton 121. Of course, in other embodiments, the diffusion plate 122 can also be fixed on the inner wall of the cathode chamber 112. It should be noted that in the electroplating process, an ion membrane is installed on the ion membrane skeleton 121, and the ion membrane is used to control the movement of copper ions to improve the current efficiency, while the diffusion plate can redistribute the electric field and flow field between the anode and the cathode, making the distribution of the electric field and flow field between the anode and the cathode more uniform. Therefore, a constant distance also needs to be maintained between the separation component (i.e., the ion membrane skeleton and the diffusion plate) and the anode. During the electroplating process, the consumption of the anode also changes the distance between the anode and the separation component. Therefore, in this embodiment, through the telescopic side wall 1111, the positions of the ion membrane skeleton 121 and the diffusion plate 122 are adjusted, so that a constant distance is maintained between the anode 1112 and the separation component 12.

[0088] The present invention also provides an electroplating method, and the electroplating method includes:

[0089] Obtaining the reduction amount of the anode height;

[0090] Calculating the compensation displacement amounts required for the substrate holder and the separation component according to the reduction amount, and controlling the movement of the substrate holder and the separation component so that the process position of the substrate maintains a predetermined gap with the separation component, and the distance between the separation component and the anode is constant;

[0091] Electroplating the substrate.

[0092] As an example, the specific process of controlling the movement of the substrate holder and the separation component includes two methods: the substrate holder and the separation component move simultaneously based on the displacement compensation amount, or after the separation component performs a compensation displacement based on the displacement compensation amount, the substrate holder moves downward so that the process position of the substrate maintains a predetermined gap with the separation component.

[0093] As an example, the method for obtaining the reduction amount of the anode height includes collecting the height information of the anode through an anode height detector, comparing it with the original height of the anode, and calculating the reduction amount of the anode height.

[0094] Figure 2 FIG. 4 is a positional relationship diagram of each component of the electroplating device provided in this embodiment in the initial state. The initial state is the state when the anode target of the electroplating device is not consumed. A is the initial position of the substrate clamp 131, B is the initial position of the separation component 12, d1 is the distance between the substrate 15 and the anode 1112, d2 is the distance between the separation component 12 and the anode 1112, d3 is the distance between the substrate 15 and the separation component 12, and h is the original height of the anode; Figure 3 FIG. 5 is a positional relationship diagram of each component of the electroplating device provided in this embodiment in the electroplating process position. A' is the electroplating process position of the substrate clamp 131, B' is the electroplating process position of the separation component 12, and h1 is the reduction amount of the anode height.

[0095] Specifically, in combination with Figure 1 and Figure 2 、 Figure 3 、a method for electroplating based on the electroplating device provided in this embodiment is described as follows: The anode height detector 14 collects the height information of the anode 1112 and compares it with the original height h of the anode, calculates the reduction amount h1 of the anode 1112 height. The first driver 132 drives the substrate support 13 to drive the substrate clamp 131 to perform displacement compensation movement from the initial position A to the electroplating process position A' according to the reduction amount h1 of the anode height. At the same time, the substrate support 13 drives the slider 1113 to move downward through the top push rod 1116, so that the separation component 12 moves from the initial position B of the separation component to the electroplating process position B'. The distance from A to A' and the distance from B to B' are the same as the reduction amount h1 of the anode height, so that the distance d2 between the separation component 12 and the anode 1112 and the distance d3 between the substrate 15 and the separation component 12 are kept constant, ensuring the uniformity of electroplating; start electroplating the substrate 15; after electroplating is completed, the first driver 132 drives the substrate clamp 131 to return to the initial position A, and the elastic component 1115 drives the telescopic side wall 1111 to return to the natural state, and correspondingly, the separation component 12 also returns to the initial position B.

[0096] In this embodiment, through the retractable design of the anode chamber, the separation component can move to keep the distance between the substrate and the anode fixed; by adding an anode height detector to collect the anode height information, the consumed height of the anode is automatically compensated to keep the distance between the substrate and the anode fixed; through the linkage design of the substrate holder and the retractable anode chamber, while adjusting the position of the substrate, the positions of the ion membrane and the diffusion plate are also adjusted, which can ensure the consistency of the positions of the substrate, the diffusion plate, the ion membrane skeleton and the anode target during electroplating, and can greatly improve the uniformity of the electric field distribution in the electroplating chamber after the consumption of the anode target and the uniformity of the electroplated product.

[0097] Embodiment 2

[0098] This embodiment provides an electroplating device. As Figure 4 shown, different from Embodiment 1, the driving mechanism of this embodiment includes: a sliding component, the sliding component includes a vertically installed slide rail 2114 and a slider 2113 moving on the slide rail 2114, and the slider 2113 is fixedly connected to the separation component 22; a second driver 2115, the second driver 2115 drives the slider 2113 to drive the retractable side wall 2111 to move up and down. Different from Embodiment 1, this embodiment uses the second driver 2115 to drive the slider 2113 to move, so that the position of the separation component 22 can be adjusted independently to ensure that the relative position of the separation component and the anode remains unchanged.

[0099] The electroplating method provided by this embodiment includes the step of driving the separation component to perform a compensation displacement by the second driver 2115, and then the substrate holder moves down to keep a predetermined gap between the process position of the substrate and the separation component. According to Figure 4 and combined with Figure 2 、 Figure 3 Specifically, the electroplating method based on the electroplating device provided by this embodiment is described as follows: the height information of the anode 2112 is collected by the anode height detector 24 and compared with the original height h of the anode, and the height reduction amount h1 of the anode 2112 is calculated. The second driver 2115 drives the separation component 22 to perform displacement compensation according to the anode height reduction amount h1. After moving the separation component from the initial position B to the electroplating process position B', the first driver 232 drives the substrate clamp 231 to perform displacement compensation and move from the initial position A to the electroplating process position A', so that the distance d2 between the separation component 22 and the anode 2112 and the distance d3 between the substrate 25 and the separation component 22 are kept constant, ensuring the uniformity of electroplating; start electroplating the substrate 25. After electroplating is completed, the separation component 22 can continue to stay in the electroplating process position to facilitate the next electroplating process.

[0100] The other technical solutions of this embodiment are the same as those of the first embodiment and will not be elaborated here. By adding a second driver in this embodiment, the separate control of the separation component is realized, so that the relative position between the separation component and the anode target can be adjusted separately.

[0101] In this embodiment, through the telescopic design of the anode chamber, the separation component can move to keep the distance between the substrate and the anode target fixed; by adding an anode height detector to collect the anode height signal, the consumed height of the anode target can be compensated to keep the distance between the cathode substrate and the anode target fixed; by adding a second driver, the separation component can be controlled separately, which can ensure the consistency of the positions of the cathode substrate, the diffusion plate, the ion membrane skeleton and the anode target during electroplating, and can greatly improve the uniformity of the electric field distribution in the electroplating chamber after the consumption of the anode target and the uniformity of the electroplated product.

[0102] In summary, the present invention provides an electroplating device and an electroplating method. The electroplating device includes: an electroplating chamber for containing electroplating solution, the inside of the electroplating chamber is separated into an anode chamber and a cathode chamber by a separation component, and an anode is accommodated in the anode chamber; a substrate holder, the substrate holder includes a first driver and a substrate clamp, the substrate clamp is used to hold the substrate, and the first driver is used to drive the substrate clamp to move up and down so that the process position of the substrate maintains a predetermined gap with the separation component; wherein, the anode is a consumable anode, and the separation component is configured to be movable relative to the anode to maintain a constant distance between the separation component and the anode. Through the telescopic design of the anode chamber, the separation component can move to keep the distance between the substrate and the anode fixed; by adding an anode height detector to collect the anode height signal, the consumed height of the anode can be automatically compensated to keep the distance between the substrate and the anode fixed; through the linkage design of the substrate holder and the telescopic anode chamber, the positions of the ion membrane and the diffusion plate are also adjusted while adjusting the position of the substrate, which can ensure the consistency of the positions of the substrate, the diffusion plate, the ion membrane skeleton and the anode target during electroplating, and can greatly improve the uniformity of the electric field distribution in the electroplating chamber after the consumption of the anode target and the uniformity of the electroplated product.

[0103] Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value. The above embodiments are only illustrative of the principles and effects of the present invention and are not used to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. An electroplating device, characterized in that, At least including: An electroplating chamber for containing electroplating solution, the interior of the electroplating chamber is separated by a separating component into an anode chamber and a cathode chamber, and an anode is accommodated in the anode chamber; A substrate holder located outside the electroplating chamber, the substrate holder includes a first driver and a substrate clamp, the substrate clamp is used to hold the substrate, and the first driver is used to drive the substrate clamp to move up and down so that the process position of the substrate maintains a predetermined gap from the separating component; Wherein, the anode is a consumable anode, and the separating component is configured to be movable relative to the anode to maintain a constant distance between the separating component and the anode; A telescopic side wall, and the separating component is installed on the top of the telescopic side wall; A driving mechanism located outside the electroplating chamber, the driving mechanism is used to drive the telescopic side wall to move up and down so that the distance between the separating component and the anode is constant.

2. The electroplating apparatus according to claim 1, characterized in that, The driving mechanism includes: A sliding component, the sliding component includes a vertically installed slide rail and a slider moving on the slide rail, and the slider is fixedly connected to the telescopic side wall; An elastic component for elastically supporting the slider; A push rod connected to the first driver. When the first driver drives the push rod to move down, the push rod pushes the slider to move down synchronously and drives the separating component to descend. When the first driver drives the push rod to return to the initial position, the separating component is reset under the action of the elastic component.

3. The electroplating device according to claim 1, characterized in that, The driving mechanism includes: A sliding component, the sliding component includes a vertically installed slide rail and a slider moving on the slide rail, and the slider is fixedly connected to the telescopic side wall; A second driver, and the second driver drives the slider to drive the telescopic side wall to move up and down.

4. The electroplating device according to claim 1, wherein, The separating component includes an ion membrane skeleton fixedly installed on the top of the anode chamber.

5. The electroplating device according to claim 4, characterized in that, The separating component further includes a diffusion plate fixedly installed on the ion membrane skeleton.

6. The electroplating apparatus according to any one of claims 1 to 5, characterized in that, It further includes an anode height detector for collecting anode target height information to determine the compensation displacement of the separating component or the substrate holder.

7. An electroplating method, characterized by using any one of the electroplating apparatuses described in claims 1 to 6. Including steps: Obtaining the reduction amount of the anode height; Calculating the required compensation displacement amounts of the substrate holder and the separating component according to the reduction amount, and controlling the movement of the substrate holder and the separating component so that the process position of the substrate maintains a predetermined gap from the separating component and the distance between the separating component and the anode is constant; Electroplating the substrate.

8. The electroplating method according to claim 7, characterized in that, The method for obtaining the reduction amount of the anode height includes collecting the height information of the anode through an anode height detector and comparing it with the original height of the anode to calculate the reduction amount of the anode height.

9. The electroplating method according to claim 7 or 8, characterized in that, The substrate holder and the separating component move simultaneously based on the compensation displacement amount.

10. The electroplating method according to claim 7 or 8, characterized in that, After the separating component performs a compensation displacement based on the compensation displacement amount, the substrate holder moves down so that the process position of the substrate maintains a predetermined gap from the separating component.

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