Electroplating equipment

Abstract

The utility model provides electroplating equipment, which comprises an electroplating bath, an electroplating device and a control device, wherein the electroplating bath is used for accommodating electroplating liquid; the plating head is used for filling the electroplating liquid into the holes of the wafer; and the megasonic generation device is arranged on the side wall of the electroplating bath and is used for generating megasonic waves during electroplating and acting on the wafer at a preset angle, so that the hole of the wafer is completely filled with the electroplating liquid. According to the electroplating equipment disclosed by the utility model, the megasonic generation device is arranged on the outer wall of the electroplating bath, so that a controllable, stable and safe megasonic environment is provided for electroplating, an electroplating solution can fully enter a deeper wafer hole, a wafer is not directly placed in megasonic waves, and a wafer seed layer is prevented from being damaged while an expected electroplating effect is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to TSV electroplating technical field, especially relates to a kind of electroplating equipment. BACKGROUND

[0002] Through Silicon Via (TSV) electroplating technology can realize vertical electrical interconnection of through hole in silicon wafer, and this technology is the only vertical electrical interconnection technology, and is one of key technologies for realizing 3D advanced packaging.TSV technology can realize vertical conduction between wafer and wafer and vertical conduction between chips, so as to realize wafer stacking and chip stacking, and the purpose is to greatly improve chip performance, and it is one of important technologies for solving the failure of Moore's law.TSV technology can make multiple chips vertically stacked, improve performance while greatly reducing the substrate space occupied by chips.As the core technologies of TSV technology, such as deep silicon etching and copper electroplating, gradually develop maturely, TSV technology is more widely applied.

[0003] To meet the above requirements, 3D packaging of chip is more and more widely used, and metal copper interconnection is the basis for realizing all this.The existing research shows that electroplated copper TSV technology plays an important role in 3D interconnection, can maintain chip interconnection at a very small size, shorten signal transmission path, reduce RC delay and reduce signal transmission power.The key to developing defect-free TSV electroplating process is to add additive components in the chemical solution, i.e., leveling agent, brightener and wetting agent and their relative diffusion / adsorption characteristics, which can produce copper deposition without gap and joint.

[0004] With the continuous increase of aspect ratio of TSV hole, it is more and more difficult to realize defect-free TSV electroplating.Because the general TSV is electroplated under the structure of blind hole, then the wafer is turned over, the back is polished and thinned to expose the electroplated metal, such as copper, at the bottom of the original blind hole.So in the process of TSV hole filling electroplating, for the hole with large aspect ratio, the additive may also not meet the effect of gap-free electroplating, that is, due to the existence of air in the hole and the effect of surface tension of chemical solution, the electroplating chemical solution may not reach the bottom of the hole.If the electroplating chemical solution cannot enter the bottom of the hole, metal copper cannot be deposited on the seed layer in the hole, and the reason why the electroplating chemical solution cannot enter the deep hole is mainly that the gas in the hole cannot escape under the action of air pressure and water pressure, and the surface tension of electroplating chemical solution prevents the chemical solution from wetting the side wall and bottom of the hole. UTILITY MODEL CONTENTS

[0005] The technical problem to be solved by the utility model is to overcome the defect that the electroplating solution cannot fully enter the deeper TSV hole in the prior art, and to provide an electroplating equipment.

[0006] The present invention solves the above-mentioned technical problems through the following technical solution:

[0007] This utility model provides an electroplating device, the electroplating device comprising:

[0008] An electroplating tank, used to hold electroplating solution;

[0009] A plating head, used to fill the electroplating solution into the holes of the wafer;

[0010] A megohmonic wave generating device is disposed on the side wall of the electroplating tank to generate megohmonic waves during electroplating and apply them to the wafer at a preset angle so that the pores of the wafer are completely filled with the electroplating solution.

[0011] Preferably, the side wall of the electroplating tank is provided with a protrusion, and the megohmonic wave generating device is disposed on the protrusion to form a preset angle with the horizontal plane.

[0012] Preferably, the protrusion is a window on the side wall of the electroplating tank that is enclosed by an upper inclined surface and a lower inclined surface.

[0013] Preferably, the megasonic wave generating device includes a substrate array composed of several megasonic wave transducer substrates of different frequencies; the frequencies of adjacent megasonic wave transducer substrates are different.

[0014] Preferably, the arrangement of the substrate array includes at least one of the following: hexagonal substrates arranged in a honeycomb pattern, quadrilateral substrates arranged in a rectangle, triangular substrates arranged in a rectangle, or trapezoidal substrates arranged in a rectangle.

[0015] The substrate is made of a piezoelectric material.

[0016] Preferably, the megasonic transducer substrates of the same frequency are connected in parallel to form an independent circuit;

[0017] The electroplating equipment also includes a controller for controlling the conduction of corresponding independent circuits during a preset time period in the electroplating process, so that the megasonic transducer substrate of the corresponding frequency generates megasonic waves of the preset frequency.

[0018] Preferably, each of the parallel megaacoustic transducer substrates is individually connected to a power supply; or,

[0019] Each parallel megaacoustic transducer substrate is connected to the same power supply, and each independent circuit is equipped with a branch switch.

[0020] Preferably, the megasonic wave generating device further includes a megasonic wave propagation structure having opposing first and second sidewalls, the first sidewall being disposed on the lower inclined surface, and the second sidewall being disposed on the substrate array.

[0021] The cavity of the megasonic wave propagation structure contains a megasonic wave propagation medium. The megasonic waves generated by the substrate array propagate through the megasonic wave propagation structure to the electroplating solution and act on the wafer surface.

[0022] Preferably, a quartz plate is embedded between the first sidewall of the megaacoustic wave propagation structure and the lower inclined surface of the sidewall of the electroplating tank by fasteners, and the second sidewall includes a stainless steel plate.

[0023] The cavity of the mega-sound propagation structure is a stainless steel cavity or a polyvinylidene fluoride cavity.

[0024] Preferably, the plating head includes a rotating plating head.

[0025] The positive and progressive effects of this utility model are as follows:

[0026] The electroplating equipment of this invention provides a controllable, stable, and safe megasonic environment for electroplating by placing a megasonic wave generating device on the outer wall of the electroplating tank. By using a splicing arrangement of substrates of different thicknesses, different combinations of megasonic frequencies are achieved, allowing the electroplating solution to fully penetrate deeper wafer cavities without directly placing the wafer in the megasonic waves. This achieves the desired electroplating effect while avoiding damage to the wafer seed layer. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0028] Figure 1 This is a first structural schematic diagram of an electroplating device according to an embodiment of the present invention.

[0029] Figure 2 This is a schematic diagram of the second structure of an electroplating device according to an embodiment of the present invention.

[0030] Figure 3 This is a schematic diagram of the first structure of the substrate array of an electroplating device according to an embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of the second structure of the substrate array of an electroplating device according to an embodiment of the present invention.

[0032] Figure 5 This is a schematic diagram of the third structure of the substrate array of an electroplating device according to an embodiment of the present invention. Detailed Implementation

[0033] The present invention will be described more clearly and completely below with reference to the accompanying drawings, using a preferred embodiment.

[0034] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the document does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0035] It should be understood that the terms “device,” “system,” “unit,” and / or “module” used herein are one way to distinguish different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0036] As illustrated herein, unless the context clearly indicates otherwise, the words “a,” “an,” “an,” and / or “the” do not specifically refer to the singular and may also include the plural. Generally speaking, the terms “comprising” and “including” only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0037] The definitions used herein, such as the terms “having,” “may have,” “comprising,” or “may include,” indicate the presence of the corresponding function, operation, element, etc., and do not limit the presence of one or more other functions, operations, elements, etc. Furthermore, it should be understood that the terms “comprising” or “having” as used herein indicate the presence of the features, figures, steps, operations, elements, components, or combinations thereof described in the specification, without excluding the presence or addition of one or more other features, figures, steps, operations, elements, components, or combinations thereof.

[0038] Example 1

[0039] Please refer to Figure 1 This is a first structural schematic diagram of the electroplating equipment in this embodiment. The electroplating equipment in this embodiment can be used for TSV electroplating; as... Figure 1 As shown, the electroplating equipment includes:

[0040] Electroplating tank 1, used to hold electroplating solution;

[0041] Plating head 2 is used to fill the through-hole of the wafer with electroplating solution;

[0042] The megasonic wave generating device 3 is installed on the side wall of the electroplating tank 1 to generate megasonic waves during electroplating and apply them to the wafer 4 at a preset angle so that the holes of the wafer are completely filled with the electroplating solution.

[0043] Specifically, compared to traditional ultrasound, megasonic waves, with their higher frequencies (above 1 MHz), can reduce damage to wafers. By optimizing electroplating solution dynamics, improving mass transfer efficiency, and enhancing surface activation, the electroplating solution can fully penetrate deeper wafer cavities, significantly improving coating quality and process stability. Furthermore, the megasonic wave generator is located on the outer wall of the electroplating tank, rather than placing the wafer directly in the megasonic waves, thus avoiding damage to the wafer seed layer while achieving the desired electroplating effect.

[0044] In this embodiment, the side wall of the electroplating tank is provided with a protrusion 5, and the megasonite generating device is disposed on the protrusion 5 to form a preset angle with the horizontal plane.

[0045] In one alternative embodiment, the protrusion 5 is a window on the side wall of the electroplating tank, enclosed by an upper inclined surface and a lower inclined surface. Preferably, as shown... Figure 1 As shown, the cross-section of the window enclosed by the upper and lower inclined surfaces is an equilateral triangle.

[0046] Please refer to Figure 2 This is a schematic diagram of the second structure of the electroplating equipment in this embodiment. The diagram is a side view of the electroplating equipment, as shown below. Figure 2 As shown, a substrate array 31, consisting of several megaacoustic transducer substrates of different frequencies, is disposed on a protrusion on the side wall of the electroplating tank.

[0047] Please refer to Figure 3 This is a schematic diagram of the first structure of the substrate array 31 of the electroplating equipment in this embodiment, as shown below. Figure 3 As shown, in this embodiment, the megasonic wave generating device 3 includes a substrate array 31 composed of several megasonic wave transducer substrates of different frequencies; adjacent megasonic wave transducer substrates have different frequencies. Specifically, the substrates of the megasonic wave transducers can have at least several different thicknesses to correspond to different frequencies. Taking three thicknesses as an example, each corresponds to a different frequency.

[0048] The substrate is made of piezoelectric materials, such as lead zirconate titanate, barium titanate, alumina, and potassium sodium niobate.

[0049] Preferably, each substrate has a size of 3cm to 5cm.

[0050] Preferably, the plating head is a rotary plating head.

[0051] like Figure 1As shown, the megasonic wave generating device 3 also includes a megasonic wave propagation structure 32. The megasonic wave propagation structure 32 has opposing first and second sidewalls. The first sidewall of the megasonic wave propagation structure 32 is disposed on a downwardly inclined surface, and the substrate array 31 is disposed on the second sidewall of the megasonic wave propagation structure 32. Specifically, a quartz plate 6 is embedded between the first sidewall of the megasonic wave propagation structure 32 and the downwardly inclined surface of the electroplating tank sidewall by fasteners. The second sidewall includes a stainless steel plate 7, and the substrate array 31 can be bonded to the back of the stainless steel plate 7 by conductive adhesive. The cavity of the megasonic wave propagation structure 32 is a stainless steel cavity or a PVDF (polyvinylidene difluoride) cavity. The cavity of the megasonic wave propagation structure 32 contains a megasonic wave propagation medium. The megasonic waves generated by the substrate array 31 propagate to the electroplating solution through the megasonic wave propagation structure 32 and act on the wafer surface. The downwardly inclined surface of the protrusion 5 is embedded with a quartz plate by fasteners and is sealed on all sides. A sealed stainless steel cavity or PVDF cavity can be set on the quartz by bonding (if a PVDF cavity is used, a stainless steel plate 7 is set on one side of the PVDF cavity, and the substrate array 31 is bonded to the back of the stainless steel plate 7 with conductive adhesive). Water is filled in the stainless steel or PVDF cavity through an inlet pipe 81 and an outlet pipe 82, which serves as the propagation medium for megasonic waves. The megasonic transducer is bonded to the back of the stainless steel cavity or the back of the stainless steel plate set on the PVDF with conductive adhesive. The circuit loop 9 can control the opening and closing of each megasonic transducer substrate. The propagation path of the megasonic wave is stainless steel, water, quartz, electroplating solution, and finally acts on the wafer.

[0052] In one optional embodiment, the substrate array is arranged in at least one of the following ways: hexagonal substrates arranged in a honeycomb pattern, quadrilateral substrates arranged in a rectangle, triangular substrates arranged in a rectangle, or trapezoidal substrates arranged in a rectangle; please refer to Figures 4-5 These are schematic diagrams of the second and third structures of the substrate array of the electroplating equipment in this embodiment. Each color in the diagram represents a substrate of a certain frequency, and the three colors correspond to different resonant fundamental frequencies. Figure 4 As shown, the substrate array is arranged in a honeycomb pattern with hexagonal substrates, such as... Figure 5 As shown, the substrate array is arranged in a rectangular pattern of quadrilateral substrates. The start-up, continuous operation, and termination times of megasonic transducers on substrates of the same color, as well as the repetition vibration time parameters, can be controlled by software. Transducers of different colors can be controlled by software to operate in a time-sharing manner, ensuring that transducers of different frequencies are operating at different times. By using a combination of megasonic transducers of different frequencies, the electroplating solution can more easily penetrate the cavities at different depths on the wafer.

[0053] Specifically, megasonic transducer substrates of the same frequency are connected in parallel to form an independent circuit. The electroplating equipment also includes a controller for controlling the conduction of the corresponding independent circuits during a preset time period in the electroplating process, so that the megasonic transducer substrates of the corresponding frequencies generate megasonic waves of the preset frequency. Taking three different megasonic transducers as an example, the substrates of the megasonic transducers of the same frequency are connected in parallel and connected to the anode of the corresponding power supply, and one side of the stainless steel cavity is connected to the cathode of the power supply to form a circuit.

[0054] In one alternative implementation, each parallel megasonic transducer substrate is individually connected to a power supply.

[0055] In another alternative implementation, each parallel megasonic transducer substrate is connected to the same power supply, and each independent circuit is equipped with a branch switch.

[0056] Taking three different megasonic transducers as an example, substrates of the same frequency from the megasonic transducers are connected in parallel and connected to the anode of the corresponding power supply. One side of the stainless steel cavity is connected to the cathode of the power supply, forming a circuit. Each parallel transducer substrate can be connected to a separate power supply, i.e., three power supplies; or the three parallel substrates can be connected to the same power supply, with each circuit having a branch switch. Both methods allow for the individual driving of substrates at the same frequency to vibrate within a specific time period. For example, in the electroplating process, the first time period might use 950 kHz, the second 930 kHz, and the third 900 kHz. The division of time periods depends on the process requirements. During electroplating, since the plating head rotates, the megasonic waves can cover all the holes in the wafer after one rotation cycle.

[0057] The electroplating equipment of this embodiment provides a controllable, stable, and safe megasonic environment for electroplating by placing the megasonic wave generator on the outer wall of the electroplating tank, and does not place the wafer directly in the megasonic waves. This avoids damaging the wafer seed layer while achieving the desired electroplating effect. By controlling the start-up, continuous operation, and end time of the megasonic wave transducer of the same frequency, as well as the repetition vibration time parameter and the periodic megasonic wave operation mode, the electroplating solution can easily enter the holes with different aspect ratios.

[0058] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. An electroplating device, characterized in that, The electroplating equipment includes: Electroplating tank, used to hold electroplating solution; A plating head, used to fill the electroplating solution into the holes of the wafer; A megohmonic wave generating device is disposed on the side wall of the electroplating tank to generate megohmonic waves during electroplating and apply them to the wafer at a preset angle so that the pores of the wafer are completely filled with the electroplating solution.

2. The electroplating equipment as described in claim 1, characterized in that, The side wall of the electroplating tank is provided with a protrusion, and the megasonite generating device is disposed on the protrusion to form a preset angle with the horizontal plane.

3. The electroplating equipment as described in claim 2, characterized in that, The protrusion is a window on the side wall of the electroplating tank, enclosed by an upper inclined surface and a lower inclined surface.

4. The electroplating equipment as described in claim 3, characterized in that, The megasonic wave generating device includes a substrate array composed of several megasonic wave transducer substrates of different frequencies; the frequencies of adjacent megasonic wave transducer substrates are different.

5. The electroplating equipment as described in claim 4, characterized in that, The arrangement of the substrate array includes at least one of the following: hexagonal substrates arranged in a honeycomb pattern, quadrilateral substrates arranged in a rectangle, triangular substrates arranged in a rectangle, or trapezoidal substrates arranged in a rectangle. The substrate is made of a piezoelectric material.

6. The electroplating equipment as described in claim 4, characterized in that, The megaacoustic transducer substrates of the same frequency are connected in parallel to form an independent circuit; The electroplating equipment also includes a controller for controlling the conduction of corresponding independent circuits during a preset time period in the electroplating process, so that the megasonic transducer substrate of the corresponding frequency generates megasonic waves of the preset frequency.

7. The electroplating equipment as described in claim 6, characterized in that, Each parallel megaacoustic transducer substrate is individually connected to a power supply; or... Each parallel megaacoustic transducer substrate is connected to the same power supply, and each independent circuit is equipped with a branch switch.

8. The electroplating equipment as described in claim 4, characterized in that, The megaacoustic wave generating device further includes a megaacoustic wave propagation structure, which has a first sidewall and a second sidewall opposite to each other. The first sidewall is disposed on the lower inclined surface, and the second sidewall is disposed on the substrate array. The cavity of the megasonic wave propagation structure contains a megasonic wave propagation medium. The megasonic waves generated by the substrate array propagate through the megasonic wave propagation structure to the electroplating solution and act on the wafer surface.

9. The electroplating equipment as described in claim 8, characterized in that, A quartz plate is embedded between the first sidewall of the megaacoustic wave propagation structure and the lower inclined surface of the sidewall of the electroplating tank by fasteners, and the second sidewall includes a stainless steel plate. The cavity of the mega-sound propagation structure is a stainless steel cavity or a polyvinylidene fluoride cavity.

10. The electroplating equipment as described in claim 1, characterized in that, The plating head includes a rotating plating head.

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