Electroplating tank and electroplating apparatus

Abstract

The application discloses an electroplating tank and an electroplating device, and relates to the technical field of electroplating devices.The electroplating tank comprises a tank body, a containing cavity is formed in the tank body, and the containing cavity is used for containing electroplating liquid; an evaporation cover is arranged at the top of the containing cavity; an evaporation gas flow channel is formed in the evaporation cover; a plurality of through holes are arranged on the side surface of the evaporation cover in the containing cavity; and the plurality of through holes are respectively connected with the containing cavity and the evaporation gas flow channel, so that water vapor in the containing cavity is evaporated when evaporation gas flows through the evaporation gas flow channel.The electroplating tank and the electroplating device provided by the application increase the concentration of the electroplating liquid in a non-heating mode, thereby improving the electroplating efficiency and avoiding waste.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electroplating equipment, in particular to an electroplating tank and electroplating equipment. BACKGROUND

[0002] Wafer refers to a silicon wafer used for manufacturing silicon semiconductor integrated circuits. Since the shape of the wafer is circular, it is called a wafer. A layer of conductive metal is electroplated on the wafer, and the conductive metal layer is processed to form a conductive circuit. Electroplating is one of the key processes for manufacturing these metal layers. Wafer electroplating involves placing a wafer in an electroplating solution, applying a negative voltage to a pre-made thin metal layer on the wafer, and applying a positive voltage to a soluble or insoluble anode. Through the action of the electric field, metal ions in the electroplating solution are deposited onto the wafer surface. During the electroplating process, stable control of the concentration of the electroplating solution is a core link in production, as stable control of the electroplating solution is a necessary adjustment condition for producing high-quality electroplated layers, and is a key factor in the uniformity of the thickness distribution of the electroplated layer, the coarseness of the electroplated layer, and the surface finish of the product.

[0003] Specifically, in the prior art, when the concentration of the electroplating solution is too high, water can be added to the electroplating tank to dilute the electroplating solution and reduce the concentration of the electroplating solution. When the concentration of the electroplating solution is too low, some methods use heating and evaporation to evaporate water in the electroplating solution and increase the concentration of the electroplating solution. Some methods can only stop the electroplating operation and replace the electroplating solution with a new one that meets the concentration standard. The heating and evaporation method is slow and requires heating the entire electroplating solution, which wastes energy. Replacing the electroplating solution stops the production and affects the electroplating efficiency, and also wastes the electroplating solution. SUMMARY

[0004] The present application aims to provide an electroplating tank and electroplating equipment that uses a non-heating method to increase the concentration of the electroplating solution, thereby improving the electroplating efficiency and avoiding waste.

[0005] An embodiment of the present application provides an electroplating tank. The electroplating tank includes a tank body, a containing cavity formed in the tank body for holding an electroplating solution, and an evaporation cover provided at the top of the containing cavity. An evaporation gas flow channel is formed in the evaporation cover. A plurality of through holes are provided on the side of the evaporation cover inside the containing cavity. The plurality of through holes respectively communicate the containing cavity and the evaporation gas flow channel, so that the evaporation gas flows through the evaporation gas flow channel to evaporate the water vapor in the containing cavity.

[0006] As an implementable way, opposite ends of the evaporation cover are respectively provided with an inlet and an outlet. The inlet and the outlet respectively communicate with the evaporation gas flow channel.

[0007] As an implementable manner, the concentration sensor is arranged in the tank to measure the concentration of the electroplating solution, the flow inlet and the flow outlet are respectively provided with automatic regulating valves to be connected with the controller of the electroplating device, the concentration sensor is connected with the controller, and the controller controls the opening and closing size of the automatic regulating valves according to the concentration of the electroplating solution detected by the concentration sensor to adjust the rate of the evaporation gas entering or flowing out of the evaporation gas flow channel.

[0008] As an implementable manner, the concentration sensor includes an acid concentration meter and a plating layer ion concentration meter, the acid concentration meter and the plating layer ion concentration meter are respectively connected with the controller, and the controller controls the opening and closing size of the automatic regulating valves when the concentration sensor or the plating layer ion concentration meter exceeds a threshold value.

[0009] As an implementable manner, the electroplating tank includes an additive mechanism in communication with the accommodation cavity, the additive mechanism includes a storage cavity and a control assembly, the storage cavity is used to place additives, and the control assembly is connected with the controller to control the flow of the additives in the storage cavity to the accommodation cavity under the control of the controller.

[0010] As an implementable manner, the additive mechanism includes an acid additive sub-mechanism and a plating layer ion additive sub-mechanism.

[0011] As an implementable manner, a plurality of through holes are uniformly arranged on the side of the evaporation cover located in the accommodation cavity.

[0012] As an implementable manner, the through hole is a circular hole, and the diameter of the circular hole is between 5-10 cm.

[0013] As an implementable manner, the evaporation gas is nitrogen.

[0014] Another aspect of the embodiments of the present application provides an electroplating device including the electroplating tank.

[0015] The beneficial effects of the embodiments of the present application include:

[0016] The electroplating tank provided by the application comprises a tank body, a containing cavity is formed in the tank body, and the containing cavity is used for containing electroplating solution. A plated part is placed in the electroplating solution, so that plating layer ions in the electroplating solution are plated on the surface of the plated part under the action of an electric field. An evaporation cover is arranged at the top of the containing cavity. An evaporation gas flow channel is formed in the evaporation cover. A plurality of through holes are arranged on the side of the evaporation cover in the containing cavity. The plurality of through holes are respectively connected with the containing cavity and the evaporation gas flow channel, so that water vapor in the containing cavity is evaporated by evaporation gas flowing through the evaporation gas flow channel. In the process of plating the plating layer ions on the plated part, the electroplating solution has a certain temperature, so that water in the electroplating solution is evaporated into water vapor and stored above the electroplating solution in the containing cavity. When the concentration of the electroplating solution is low, the evaporation gas flows through the evaporation gas flow channel, so that the pressure in the evaporation gas flow channel decreases. The evaporation gas flow channel is arranged inside the evaporation cover, and the through holes are connected with the containing cavity and the evaporation gas flow channel. When the pressure in the evaporation gas flow channel decreases, the water vapor in the containing cavity enters the evaporation gas flow channel through the through holes and flows out along the evaporation gas flow channel, so that more water in the electroplating solution is evaporated into water vapor and discharged with the evaporation gas, thereby increasing the concentration of the electroplating solution and improving the electroplating efficiency, and waste is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0018] Figure 1 FIG. 1 is a structural schematic diagram of an electroplating tank provided by an embodiment of the application;

[0019] Figure 2 FIG. 2 is another structural schematic diagram of an electroplating tank provided by an embodiment of the application.

[0020] FIG. 1 is a structural schematic diagram of an electroplating tank provided by an embodiment of the application; FIG. 2 is another structural schematic diagram of an electroplating tank provided by an embodiment of the application; FIG. 3 is a structural schematic diagram of an electroplating tank provided by another embodiment of the application; 10, electroplating tank; 11, tank body; 111, containing cavity; 12, evaporation cover; 121, evaporation gas flow channel; 122, through hole; 123, inlet; 124, outlet; 13, automatic regulating valve; 14, concentration sensor; 141, acid concentration meter; 142, plating layer ion concentration meter; 151, storage cavity; 152, control assembly; 153, acid adding sub-mechanism; 154, plating layer ion adding sub-mechanism; 20, electroplating solution. DETAILED DESCRIPTION

[0021] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application.

[0023] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0024] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "vertical", "horizontal", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly placed when the product of the present application is used, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0025] In the description of the present application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "arrange", "mount", "connect", "connect" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0026] In the process of semiconductor preparation, forming a metal plating layer on a wafer is the premise of preparing a wafer conductive circuit. Specifically, the prior art adopts electroplating to form a metal plating layer on a wafer. In the electroplating process, stable control of the electroplating solution concentration is the core link of production.

[0027] The embodiments of the present application provide an electroplating tank 10, such as Figure 1 , Figure 2As shown, the electroplating tank 10 includes a tank body 11, the tank body 11 is formed with a receiving cavity 111 for containing the electroplating solution 20, the top of the receiving cavity 111 is provided with an evaporation cover 12, the evaporation cover 12 is formed with an evaporation gas flow channel 121, the evaporation cover 12 is provided with a plurality of through holes 122 on the side surface in the receiving cavity 111, the plurality of through holes 122 are respectively connected with the receiving cavity 111 and the evaporation gas flow channel 121, so that the evaporation gas flows through the evaporation gas flow channel 121 to evaporate the water vapor in the receiving cavity 111.

[0028] The electroplating tank 10 provided by the embodiment of the present application is applied to the electroplating equipment and cooperates with other components in the electroplating equipment to realize the plating of the metal layer on the surface of the workpiece to be plated. Specifically, the electroplating tank 10 of the embodiment of the present application is provided with the evaporation cover 12 on the top of the electroplating tank 10, the evaporation cover 12 is used to accelerate the evaporation of the water in the electroplating solution 20, the number of ions in the electroplating solution 20 is unchanged, and the quality of the solvent water is reduced, thereby improving the concentration of the electroplating solution 20. Specifically, the electroplating tank 10 includes the tank body 11, the tank body 11 is formed with the receiving cavity 111, the receiving cavity 111 contains the electroplating solution 20, when the workpiece to be plated is placed in the electroplating solution 20, the plating layer ions in the electroplating solution 20 move to the surface of the workpiece to be plated under the action of the electric field, and the plating layer is formed on the surface of the workpiece to be plated. When the plating layer ions are plated on the workpiece to be plated, the electroplating solution 20 has a certain temperature, so that the water in the electroplating solution 20 evaporates into water vapor and moves to the upper part of the electroplating solution 20 in the receiving cavity 111, that is, the receiving cavity 111 in the tank body 11 which does not contain the electroplating solution 20 is filled with water vapor. When the concentration of the electroplating solution 20 is lower than a preset threshold, the evaporation gas is controlled to flow through the evaporation gas flow channel 121, when the evaporation gas flows through the evaporation gas flow channel 121, due to the suction effect, the pressure in the evaporation gas flow channel 121 is reduced, the evaporation gas flow channel 121 is located in the evaporation cover 12, and the through holes 122 are connected with the receiving cavity 111 and the evaporation gas flow channel 121, when the pressure in the evaporation gas flow channel 121 is reduced, the water vapor in the receiving cavity 111 enters the evaporation gas flow channel 121 through the through holes 122 and flows out along the evaporation gas flow channel 121, thereby causing more water in the electroplating solution 20 to evaporate into water vapor and be discharged with the evaporation gas, thereby improving the concentration of the electroplating solution 20, improving the electroplating efficiency, and avoiding waste.

[0029] It should be noted that the electroplating solution 20 is a solution formed by the plating layer ions and the acid dissolved in water, wherein the acid acts as an auxiliary ion to increase the conductivity of the electroplating solution 20 and inhibit the hydrolysis of the plating layer ions, and the plating layer ions are the raw materials of the plating layer, and the plating layer ions are not limited in the embodiment of the present application and can be set according to actual needs. For example, copper ions are usually used as the plating layer ions to form a copper layer on the surface of the workpiece to be plated as an electrode structure or a circuit layer.

[0030] The electroplating tank 10 provided by the application comprises a tank body 11, a containing cavity 111 is formed in the tank body 11, and the containing cavity 111 is used for containing an electroplating solution 20; a workpiece to be plated is placed in the electroplating solution 20, so that plating layer ions in the electroplating solution 20 are plated on the surface of the workpiece to be plated under the action of an electric field; an evaporation cover 12 is arranged at the top of the containing cavity 111, and an evaporation gas flow channel 121 is formed in the evaporation cover 12; a plurality of through holes 122 are arranged on the side of the evaporation cover 12 in the containing cavity 111, and the plurality of through holes 122 are respectively connected with the containing cavity 111 and the evaporation gas flow channel 121, so that water vapor in the containing cavity 111 is evaporated when evaporation gas flows through the evaporation gas flow channel 121; in the process of plating the plating layer ions on the workpiece to be plated, the electroplating solution 20 has a certain temperature, so that water in the electroplating solution 20 is evaporated into water vapor and stored above the electroplating solution 20 in the containing cavity 111; when the concentration of the electroplating solution 20 is relatively low, the evaporation gas flows through the evaporation gas flow channel 121, so that the pressure in the evaporation gas flow channel 121 is reduced; the evaporation gas flow channel 121 is arranged inside the evaporation cover 12, and the through holes 122 are connected with the containing cavity 111 and the evaporation gas flow channel 121; when the pressure in the evaporation gas flow channel 121 is reduced, the water vapor in the containing cavity 111 enters the evaporation gas flow channel 121 through the through holes 122 and flows out along the evaporation gas flow channel 121, so that more water in the electroplating solution 20 is evaporated into water vapor and discharged with the evaporation gas, thereby improving the concentration of the electroplating solution 20 and the electroplating efficiency, and avoiding waste.

[0031] Optionally, as shown in Figure 2 , the evaporation cover 12 is provided with an inlet 123 and an outlet 124 at opposite ends thereof, and the inlet 123 and the outlet 124 are respectively connected with the evaporation gas flow channel 121.

[0032] In order to facilitate the evaporation gas to flow into or out of the evaporation gas flow channel 121, the inlet 123 and the outlet 124 are arranged at opposite ends of the evaporation cover 12, the evaporation gas flows into the evaporation gas flow channel 121 through the inlet 123 and flows out of the evaporation gas flow channel 121 through the outlet 124, and the inlet 123 and the outlet 124 are arranged at opposite ends of the evaporation cover 12, so that the inlet 123 and the outlet 124 are arranged oppositely, and the evaporation gas can flow in and out more smoothly in the process of flowing.

[0033] Of course, the inlet 123 and the outlet 124 can also be arranged at two ends of the upper surface of the evaporation cover 12, as shown in Figure 1 , to facilitate the arrangement of a pipeline.

[0034] In an implementable manner of the embodiment of the application, as shown in Figure 1As shown, the concentration sensor 14 is arranged in the tank body 11 to measure the concentration of the electroplating solution 20, and the flow inlet 123 and the flow outlet 124 are respectively provided with the automatic regulating valve 13 to be connected with the controller of the electroplating device, and the concentration sensor 14 is connected with the controller, and the controller controls the opening and closing size of the automatic regulating valve 13 according to the concentration of the electroplating solution 20 detected by the concentration sensor 14 to adjust the rate of the evaporated gas entering or flowing out of the evaporated gas flow channel 121.

[0035] In order to more accurately control the concentration of the electroplating solution 20, the concentration sensor 14 is arranged in the tank body 11 to detect the ion concentration in the electroplating solution 20, and the controller controls the opening and closing size of the automatic regulating valve 13 according to the concentration detected by the concentration sensor 14 to adjust the flow rate of the evaporated gas, and then control the rate of the evaporated gas carrying water vapor, and adjust the evaporation rate of the solute in the electroplating solution 20 according to the concentration of the electroplating solution 20, so as to accurately control the concentration of the electroplating solution 20.

[0036] Optionally, as shown in Figure 1 The concentration sensor 14 includes an acid concentration meter 141 and a plating layer ion concentration meter 142, and the acid concentration meter 141 and the plating layer ion concentration meter 142 are connected with the controller, and the controller controls the opening and closing size of the automatic regulating valve 13 when the concentration sensor 14 or the plating layer ion concentration meter 142 exceeds the threshold value.

[0037] As described above, the electroplating solution 20 includes solvent water, solute acid and plating layer ions, and in order to better control the concentration in the electroplating solution 20, the embodiment of the present application is provided with the concentration sensor 14 for the two solutes to respectively measure the concentration of the acid and the concentration of the plating layer ions, and the automatic regulating valve 13 is timely controlled when one of the parameters exceeds the threshold value.

[0038] In an implementable manner of the embodiment of the present application, as shown in Figure 1 The electroplating tank 10 includes an additive mechanism in communication with the accommodating cavity 111, and the additive mechanism includes a storage cavity 151 and a control assembly 152, the storage cavity 151 is used to place the additive, and the control assembly 152 is connected with the controller to control the flow of the additive in the storage cavity 151 to the accommodating cavity 111 under the control of the controller.

[0039] Since there are two solutes in the electroplating solution 20, when the solvent water is evaporated, the concentrations of the two solutes in the electroplating solution 20 will both increase, so that the concentrations of the two solutes cannot simultaneously meet the requirements. In order to more accurately control the concentration of the electroplating solution 20, the embodiment of the present application sets an additive mechanism, which is used to add one of the solutes to the electroplating solution 20 in the solute cavity. Specifically, the acid concentration meter 141 and the plating layer ion concentration meter 142 detect the concentrations of sulfuric acid and copper ions respectively. When the concentrations of sulfuric acid and copper ions both exceed the corresponding preset threshold values, the control automatic regulating valve 13 adjusts the flow rate of the evaporated fluid to evaporate the water in the electroplating solution 20, so that one of them is within the preset threshold range. After that, the concentration of the other solute is detected. If it is within the corresponding preset threshold range, the adjustment is stopped. If it is lower than the minimum value of the preset threshold value, the adjusting control assembly 152 can be adjusted to flow the additive in the storage cavity 151 into the containing cavity 111 to increase the concentration thereof.

[0040] Optionally, as shown in Figure 1 , the additive mechanism includes an acid additive sub-mechanism 153 and a plating layer ion additive sub-mechanism 154. Sulfuric acid and copper sulfate are respectively arranged in the storage cavities 151 of the acid additive sub-mechanism 153 and the plating layer ion additive sub-mechanism 154, which are used to increase the concentrations of sulfuric acid and copper sulfate in the electroplating solution 20. The two solutes are arranged respectively to avoid affecting the amount of addition when the two solutes simultaneously use one additive mechanism.

[0041] In an implementable manner of the embodiment of the present application, as shown in Figure 2 , the plurality of through holes 122 are uniformly arranged on the side surface of the evaporation cover 12 located in the containing cavity 111.

[0042] The plurality of through holes 122 are uniformly arranged on the side surface of the evaporation cover 12 located in the containing cavity 111, so that when the evaporation gas flows, the water vapor on the upper layer of the electroplating solution 20 can be taken away, and the pressure above the electroplating solution 20 is the same. In addition, the plurality of through holes 122 are uniformly arranged, which facilitates the preparation of the electroplating tank 10 during the preparation process.

[0043] Optionally, as shown in Figure 2 , the through hole 122 is a circular hole, and the diameter of the circular hole is between 5-10 cm.

[0044] The circular hole is a commonly used hole, which is relatively easy to process during the processing of the electroplating tank 10. In addition, in order to enable the water vapor in the containing cavity 111 to smoothly enter the evaporation gas flow channel 121 and flow out with the evaporation gas, the diameter of the circular hole is set to be between 5-10 cm.

[0045] In an implementable manner of the embodiment of the present application, the evaporation gas is nitrogen.

[0046] Nitrogen is inert gas, the nature is stable, it is difficult to react with other chemical substances. In addition, nitrogen is the most abundant gas in the atmosphere, is relatively easy to obtain, the cost of nitrogen is low, thereby reducing the cost of electroplating.

[0047] The application further discloses an electroplating device, which comprises the electroplating tank 10 and the controller of any one of the above.

[0048] The above merely describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An electroplating tank, characterized in that, The device includes a tank with a cavity for holding electroplating solution. An evaporation cover is provided on the top of the cavity, and an evaporation gas channel is formed inside the evaporation cover. Multiple through holes are provided on the side of the evaporation cover inside the cavity, and the multiple through holes are respectively connected to the cavity and the evaporation gas channel so that the evaporation gas evaporates the water vapor in the cavity when it flows through the evaporation gas channel. It also includes a controller and an additive mechanism in communication with the accommodating cavity. The additive mechanism includes a storage cavity and a control component. The storage cavity is used to hold additives, and the control component is connected to the controller to control the flow of additives from the storage cavity to the accommodating cavity under the control of the controller.

2. The electroplating tank according to claim 1, characterized in that, The evaporation cap has an inlet and an outlet at opposite ends, and the inlet and outlet are respectively connected to the evaporation gas channel.

3. The electroplating tank according to claim 2, characterized in that, A concentration sensor is installed in the tank to measure the concentration of the electroplating solution. Automatic regulating valves are installed at the inlet and outlet, respectively, for connection to the controller of the electroplating equipment. The concentration sensor is connected to the controller. The controller controls the opening and closing of the automatic regulating valves according to the concentration of the electroplating solution detected by the concentration sensor, so as to regulate the rate at which the evaporating gas enters or flows out of the evaporating gas channel.

4. The electroplating tank according to claim 3, characterized in that, The concentration sensor includes an acid concentration meter and a plating ion concentration meter. The acid concentration meter and the plating ion concentration meter are respectively connected to the controller. When the concentration sensor or the plating ion concentration meter exceeds a threshold, the controller controls the opening and closing of the automatic regulating valve.

5. The electroplating tank according to claim 1, characterized in that, The additive mechanism includes an acid addition sub-mechanism and a coating ion addition sub-mechanism.

6. The electroplating tank according to claim 1, characterized in that, Multiple through holes are evenly distributed on the side of the evaporation cap located inside the accommodating cavity.

7. The electroplating tank according to claim 6, characterized in that, The through hole is a circular hole with a diameter between 5 and 10 cm.

8. The electroplating tank according to claim 1, characterized in that, The evaporated gas is nitrogen.

9. An electroplating device, characterized in that, Includes the electroplating bath as described in any one of claims 1-8.

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