Plating apparatus and plating method

Abstract

To provide a plating apparatus and a plating method for depositing a metal on a substrate having a pattern structure.SOLUTION: A plating apparatus comprises: a plating bath configured to accommodate an electrolyte; a substrate holding module configured to hold a substrate; and at least one driving device configured to vibrate the substrate holding module together with the substrate in a horizontal direction and / or a vertical direction while the substrate is immersed in the electrolyte to be plated. In the present invention, vibrating the substrate holding module can increase a plating speed, perform uniform plating on a pattern structure, and facilitate material transfer during plating.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates generally to semiconductor device manufacturing, and more particularly to a plating apparatus and method with electrolyte agitation to increase plating speed. [Background technology]

[0002] In the manufacturing of semiconductor devices, plating technology is commonly used to form metal films for wiring structures such as trenches, holes, and TSVs in the dual damascene process, and to form bumps in advanced packaging processes. With the rapid development of technology, the requirements for plating speed as well as plating quality are increasing. In both the dual damascene process and the advanced packaging process, the plating speed is becoming increasingly important because the higher the plating speed, the higher the throughput.

[0003] In general, the plating speed is related to, for example, the composition of the electrolyte, the temperature of the electrolyte, the agitation of the electrolyte, etc. Furthermore, the agitation of the electrolyte is related to, for example, the flow rate of the electrolyte, the rotation speed of the substrate to be plated, the vibration applied to the electrolyte, etc. Currently, several methods have been proposed to enhance the agitation of the electrolyte to promote mass transfer during plating and increase the plating speed. One method is to use a flow shaping plate in combination with a flow diverter with a channel opening configured to promote lateral flow. This method controls the dynamics of the electrolyte flow to obtain effective mass transfer during plating, and can result in plating with high uniformity. However, if the flow of the electrolyte from one side of the substrate to the other side is too strong, the distribution of additives in the electrolyte is affected. Specifically, the flow rate of the electrolyte on the side closer to the channel opening is faster, and the flow rate of the electrolyte on the side farther from the channel is slower. Therefore, the flow rate of the electrolyte from the center to the edge of the substrate is not uniform. More specifically, the electrolyte flow rate is high at the channel opening at the edge of the substrate, and the electrolyte flow rate becomes smaller and smaller as the electrolyte flows through the center of the substrate to the other side of the substrate, away from the channel opening. Many additives (especially plating levelers) are sensitive to the electrolyte flow rate. If the electrolyte flow rate is too high and the electrolyte flow rate distribution across the substrate is not uniform, the leveler is more likely to adhere to the substrate surface with the high electrolyte flow rate, resulting in poor plating uniformity. On the other hand, in the microstructure of semiconductor devices, the bump shape is also affected. The leveler is sensitive to the electrolyte flow rate, which causes the bump shape to tilt. Although it is possible to correct the asymmetry by rotating the substrate, the rotation speed of the substrate changes during the plating process. This is common in the industry and results in uneven plating.

[0004] Another method to enhance the stirring of the electrolyte is the paddle method, which uses the vibration of the paddle. The disadvantage of this method is that the paddle is generally placed between the diffusion plate and the substrate to be plated, and the high-speed movement of the paddle generates air bubbles in the electrolyte, which then adhere to the unplated surface of the substrate, causing problems with plating quality. Another issue caused by the paddle is that the paddle has many openings, and the pattern and size of the openings can affect the electric field distribution, causing problems with the uniformity of plating on the substrate. Furthermore, when the paddle stirs the flow adjacent to the substrate surface, a shadow is cast on the electric field in the electrolyte, causing problems with the uniformity of the plating on the substrate.

[0005] Also, to achieve higher plating speeds, electrolytes with different formulations are used than electrolytes for low-speed plating. For example, in copper plating, the conventional plating speed is 2-5 ASD, but at plating speeds over 8 ASD, specifically 8-30 ASD, the Cu ion concentration in the electrolyte becomes higher and the additives become more complex. As the plating speed increases, it becomes more difficult to control the shape of the film and bumps. In addition, when the device structure becomes complex, such as when there is both a trench and a large pad structure in one die, the strength of the leveler becomes necessary. In addition, the uniformity at the wafer level is also difficult to control with high-speed plating. In order to increase the effectiveness of plating, both at the wafer level and within the die, the additives in the electrolyte, such as accelerators, levelers, and suppressors, need to cooperate with each other.

[0006] Therefore, the current electrolyte stirring method has shortcomings. It is necessary to propose a new electrolyte stirring method to improve the plating speed and plating uniformity. Summary of the Invention

[0007] The object of the present invention is to provide a plating apparatus for depositing a metal on a substrate having a pattern structure, the plating apparatus comprising a plating bath configured to contain an electrolytic solution, a substrate-holding module configured to hold a substrate, and at least one drive configured to drive the substrate-holding module together with the substrate to oscillate horizontally and / or vertically while the substrate is immersed in the electrolytic solution to be plated.

[0008] Another object of the present invention is to provide a plating method for depositing a metal on a substrate having a pattern structure, comprising the steps of mounting and holding the substrate on a substrate holding module, immersing the substrate in an electrolytic solution contained in a plating bath, and driving the substrate holding module together with the substrate to vibrate the substrate in a horizontal and / or vertical direction while the substrate is immersed in the electrolytic solution and plating is being performed.

[0009] It is an object of the present invention to provide a plating apparatus for depositing a metal on a substrate having a pattern structure, the plating apparatus comprising a plating bath configured to contain an electrolytic solution, a substrate-holding module configured to hold a substrate, a rotary actuator configured to drive the substrate-holding module in rotation together with the substrate, and a controller configured to rotate the rotary actuator N (N≦3.0) times and then N reverse rotations for a number of cycles.

[0010] Another object of the present invention is to provide a plating method for depositing a metal on a substrate having a pattern structure, the plating method comprising the steps of mounting and holding the substrate on a substrate-holding module, immersing the substrate in an electrolytic solution contained in a plating bath, rotating the substrate-holding module together with the substrate by a rotary actuator while the substrate is immersed in the electrolytic solution and plating is being performed, and controlling the rotary actuator to rotate N (N≦3.0) times and then rotate N times in the reverse direction alternately for a number of cycles.

[0011] As described above, the present invention discloses a unique method of stirring the electrolyte while plating the substrate. The method is to vibrate the substrate-holding module together with the substrate, which can promote mass transfer so as to increase the plating speed as well as the plating uniformity. Furthermore, the vibration of the substrate-holding module is reciprocating and has a high vibration frequency, so that the additives can be distributed evenly in the pattern structure. The mass transfer boundary layer of the electrolyte becomes thinner, and the additives in the electrolyte absorbed in the pattern structure are exchanged very quickly and evenly, so that the uniformity of the plating metal in the pattern structure is improved, the problem of pillar and bump tilt is solved, and the plating speed can be increased. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram showing a conventional plating apparatus. [Diagram 2] 2A to 2C are schematic diagrams illustrating the inclination of plated metal pillars or bumps when metal is deposited using a conventional plating device. [Diagram 3] 3A to 3C are schematic diagrams illustrating the inclination of plated metal pillars or bumps when metal is deposited using a conventional plating device. [Figure 4] 1 is a schematic diagram illustrating a plating apparatus according to an exemplary embodiment of the present invention. [Diagram 5] 5A and 5B are schematic diagrams showing how the relative speed is suddenly changed to achieve stirring of the electrolyte. [Figure 6] FIG. 2 is a schematic diagram illustrating a plating apparatus according to another exemplary embodiment of the present invention. [Figure 7] 7A and 7B are schematic views showing a plating apparatus according to an exemplary embodiment of the present invention. [Figure 8] 8A and 8B are schematic diagrams showing horizontal vibrations of a substrate holding module of a plating apparatus. [Figure 9] 9A and 9B are schematic diagrams showing horizontal vibrations of a substrate holding module of a plating apparatus. [Figure 10] 10A and 10B are schematic views showing a plating apparatus according to another exemplary embodiment of the present invention. [Figure 11] 11A and 11B are schematic views showing a plating apparatus according to another exemplary embodiment of the present invention. [Figure 12] 12A and 12B are schematic views showing a plating apparatus according to an exemplary embodiment of the present invention. [Figure 13] 13A and 13B are schematic diagrams showing vertical vibrations of a substrate holding module of a plating apparatus. [Figure 14] 14A and 14B are schematic diagrams showing vertical vibrations of a substrate holding module of a plating apparatus. [Figure 15] 15A and 15B are schematic views showing a plating apparatus according to another exemplary embodiment of the present invention. [Figure 16] 16A and 16B are schematic views showing a plating apparatus according to another exemplary embodiment of the present invention. [Figure 17] 17A and 17B are schematic views showing a plating apparatus according to still another exemplary embodiment of the present invention. [Figure 18] 18A to 18C are schematic views showing a plating apparatus according to an exemplary embodiment of the present invention. [Figure 19] 19A to 19C are schematic diagrams illustrating the horizontal and vertical vibrations of a substrate holding module of a plating apparatus. [Figure 20]20A to 20C are schematic diagrams illustrating the horizontal and vertical vibrations of a substrate holding module of a plating apparatus. [Figure 21] FIG. [Figure 22] 1 is a schematic diagram illustrating a plating apparatus according to an exemplary embodiment of the present invention. [Figure 23] 1 is a schematic diagram illustrating a plating apparatus according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Please refer to FIG. 1, which shows a conventional plating apparatus 100 for depositing metal. The plating apparatus 100 includes a plating bath 110 containing an electrolytic solution, a substrate holding module 120 that holds a substrate 130 and electrically connects to the conductive surface of the substrate 130, a rotary actuator 140 that is connected to the substrate holding module 120 and rotates the substrate holding module 120 along the axis of the substrate holding module 120, an anode 150 that is disposed in the plating bath 110 and faces the conductive surface of the substrate 130, and a power source 160 that is electrically connected to the substrate holding module 120 and the anode 150. The plating apparatus 100 further includes a groove 170 that is provided around the plating bath 110 and that receives electrolytic solution that overflows from the plating bath 110. The plating apparatus 100 further includes a tank 190. A pipe 180 is connected to the groove 170 and the tank 190. The tank 190 is connected to the plating bath 110 via another pipe 180.

[0014] When the plating apparatus 100 is used to deposit metal on a substrate 130 having a pattern structure 131, the rotary actuator 140 drives the substrate holding module 120 to rotate it along its axis. An electrolyte is supplied from the center of the plating bath 110, and the electrolyte flows through the center of the substrate 130 to the edge of the substrate 130. In general, various additives such as levelers, accelerators, and retarders are added to the electrolyte to deposit metal on the substrate 130. Therefore, some additives are sensitive to the flow rate of the electrolyte. For example, in the electrolyte for Cu plating, the higher the flow rate of the electrolyte, the more likely the leveler is to adhere to the substrate surface. Therefore, when the leveler plays a major role during plating, the leveler is often retained on one side of the pattern structure 131, induced by the electrolyte flowing from the center to the edge of the substrate 130. This causes the leveler to be distributed unevenly in the pattern structure 131, which causes uneven metal deposition in the pattern structure 131 as shown in Figures 2A to 2C, resulting in tilted metal pillars or bumps. Also, for example, in an electrolyte for Cu plating, the accelerator is more sensitive to the flow rate of the electrolyte. The accelerator is more likely to adhere to a substrate surface where the electrolyte flow rate is high. In another embodiment, when the accelerator plays a major role during plating, the accelerator is induced by the electrolyte flowing from the center to the edge of the substrate 130', and tends to remain on one side of the substrate 131' on the substrate 130'. This causes the accelerator to be distributed unevenly in the pattern structure 131', which causes uneven metal deposition in the pattern structure 131' as shown in Figures 3A to 3C, resulting in tilted metal pillars or bumps. This tilt increases with increasing plating speed. New technology is needed to achieve better bump shapes at high plating speeds.

[0015] The present invention discloses a plating apparatus and plating method that solves such problems, and vibrates a substrate holding module together with the substrate when the substrate is immersed in an electrolyte for plating in order to obtain uniform metal deposition on the pattern structure of the substrate. This allows additives such as levelers, accelerators, and inhibitors to be uniformly distributed in the pattern structure and not to be concentrated in one place, suppressing the inclination of the plated metal pillars or bumps, and obtaining uniform metal deposition on the pattern structure. High-frequency vibration can reduce the thickness of the electrolyte boundary layer. By reducing the thickness of the boundary layer, a higher mass transfer rate can be achieved and the metal deposition rate can be increased.

[0016] FIG. 4 illustrates a plating apparatus for depositing metal on a substrate having a pattern structure according to an exemplary embodiment of the present invention. The plating apparatus 400 includes a plating bath 401 configured to contain an electrolyte, a substrate-holding module 402 configured to hold a substrate 403 and electrically connect with a conductive surface of the substrate 403, a rotary actuator 404 configured to rotate the substrate-holding module 402 along an axis of the substrate-holding module 402, and at least one drive device 405 configured to vibrate the substrate-holding module 402 in a horizontal and / or vertical direction. The drive device 405 may be a motor, a cylinder, or a vibrator. The plating apparatus 400 further includes at least one anode 406 disposed in the plating bath 401 and facing the conductive surface of the substrate 403, and a power source 407 electrically connected to the substrate-holding module 402 and the anode 406. A groove 408 is provided around the plating bath 401 to receive electrolyte overflowing from the plating bath 401. The plating apparatus 400 further includes a tank 410. A pipeline 409 is connected to the groove 408 and the tank 410. The tank 410 is connected to the plating bath 401 via another pipeline 409.

[0017] 5A and 5B are combined, the substrate 403 has a pattern structure 4031. When the plating apparatus 400 is used to deposit metal on the pattern structure 4031, the substrate 403 is held horizontally by the substrate holding module 402, and the substrate 403 is immersed in the plating electrolyte, while the driving device 405 drives the substrate holding module 402 and the substrate 403 to perform a reciprocating motion including horizontal and / or vertical vibration to stir the electrolyte. This promotes mass transfer so that additives such as metal ions, levelers, accelerators and inhibitors do not gather in one place while the substrate 403 is immersed in the electrolyte for plating, but are uniformly distributed on the pattern structure 4031. The tilt of the pillars or bumps of the plating metal is reduced, and uniform metal deposition on the pattern structure 4031 is obtained. Specifically, the rotary actuator 404 drives the substrate holding module 402 to rotate in its axial direction while the substrate 403 is immersed in the electrolytic solution to be plated. The electrolytic solution is supplied from the center of the plating bath 401 and flows through the center of the substrate 403 to the edge of the substrate 403 at a flow rate V2. The driving device 405 vibrates the substrate holding module 402 and the substrate 403 in the horizontal direction at a vibration speed V1. V1 is 0.2V2 or more, preferably greater than V2, and more preferably twice as large as V2. As shown in FIG. 5A, when the vibration direction is opposite to the flow direction of the electrolytic solution, the relative speed V is equal to V1+V2. As shown in FIG. 5B, when the vibration direction is the same as the flow direction of the electrolytic solution, the relative speed V is equal to V1-V2. The horizontal vibration of the substrate holding module 402 can rapidly change the relative speed V to realize stirring of the electrolytic solution, thereby facilitating mass transfer, improving the distribution uniformity of the additive in the pattern structure 4031, and further improving the plating speed and plating uniformity.

[0018] FIG. 6 shows a plating apparatus for depositing metal on a substrate having a pattern structure according to another exemplary embodiment of the present invention. The plating apparatus 600 includes a plating bath 601 configured to contain an electrolyte, a substrate holding module 602 configured to hold a substrate 603, and at least one drive device 605 configured to vibrate the substrate holding module 602 in a horizontal and / or vertical direction. The drive device 605 may be a motor, a cylinder, or a vibrator. The plating apparatus 600 further includes at least one anode 606 disposed in the plating bath 601 and facing the conductive surface of the substrate 603, and a power source 607 electrically connected to the conductive surface of the substrate 603 and the anode 606. A groove 608 is provided around the plating bath 601 to receive electrolyte overflowing from the plating bath 601. The plating apparatus 600 further includes a tank 610. A pipe 609 is connected to the groove 608 and the tank 610. The tank 610 is connected to the plating bath 601 via another line 609 .

[0019] In this embodiment, a substrate 603 having a pattern structure is held vertically by a substrate holding module 602. The substrate holding module 602 and the substrate 603 are vertically immersed in an electrolyte to deposit metal on the pattern structure. During plating, the driving device 605 drives the substrate holding module 602 and also drives the substrate 603 to perform a reciprocating motion that agitates the electrolyte, including horizontal and / or vertical vibration, to promote mass transfer so that additives such as levelers, accelerators, and retarders can be uniformly distributed in the pattern structure. While the substrate 603 is immersed in the electrolyte to be plated, the additives such as levelers, accelerators, and retarders are prevented from gathering in one place, and the tilt of the plating metal pillars or bumps is suppressed, resulting in a uniform metal deposit on the pattern structure.

[0020] 7A-9B show a plating apparatus for depositing metal on a substrate having a pattern structure according to an exemplary embodiment of the present invention. The plating apparatus 700 includes a plating bath 701, a substrate-holding module, a vibration plate 715, a mounting plate 716, a support base 717, and a driving device 705. The substrate-holding module further includes a substrate holder 702, a support column 712, a fixing device 713, a bracket 714, and a rotation actuator 704.

[0021] The plating bath 701 is configured to contain an electrolyte. The plating bath 701 may include an anode chamber and a cathode chamber for electroplating. The anode chamber and the cathode chamber are separated by a membrane disposed on a membrane frame. The anode chamber may be divided into a number of anode zones, each of which contains an anode connected to an independently controlled power source. The anode may be made of copper (Cu), titanium (Ti), titanium plate (Pt coated), etc. At least one diffusion plate 711 having a number of small openings is disposed in the cathode chamber for uniform control of the electric field and uniform control of the electrolyte flow. A groove 708 is provided around the cathode chamber to receive the electrolyte overflowing from the cathode chamber.

[0022] The substrate holder 702 is configured to hold a substrate. The support 712 is connected to the substrate holder 702 and the fixing device 713. The bracket 714 is fixed to a side of the fixing device 713. The vibration plate 715 is configured to support the substrate holding module. One end of the vibration plate 715 is connected to the bracket 714, and the other end of the vibration plate 715 is connected to a mounting plate 716. The mounting plate 716 is disposed on a support base 717. The mounting plate 716 is movable up and down along the support base 717 under the driving of a vertical actuator so as to move the vibration plate 715 up and down. The vibration plate 715 has a natural frequency. The rotation actuator 704 is disposed on the fixing device 713 and configured to drive the substrate holder 702 to rotate. The driving device 705 is disposed on the bracket 714 and configured to drive the substrate holding module to vibrate in the horizontal direction or resonate at the natural frequency of the vibration plate 715. The actuator 705 may be a vibrator, such as an inertial vibrator.

[0023] As shown in FIGS. 8A-8B and 9A-9B, the driving device 705 can drive the substrate holder 702 to vibrate in the horizontal direction while the substrate is immersed in the electrolytic solution of the object to be plated. The substrate holder 702 can perform reciprocating motion by being driven by the driving device 705. The pair of limit stop members 718 is configured to limit the amplitude of the substrate holding module so as to prevent the bracket 714 from colliding with the mounting plate 716. The pair of limit stop members 718 may be made of soft rubber. In one embodiment, the pair of limit stop members 718 are disposed on the bracket 714 and disposed on both sides of the vibration plate 715, respectively. In another embodiment, the pair of limit stop members 718 are disposed on the mounting plate 716 and disposed on both sides of the vibration plate 715, respectively.

[0024] The amplitude of the substrate holding module is related to the size of the pattern structure. In order to improve the vibration effect on the metal deposition in the pattern structure, the amplitude of the substrate holding module is preferably larger than the size of the pattern structure. The amplitude of the substrate holding module can be set to 25um to 2000um, preferably 100um to 500um.

[0025] The vibration frequency of the substrate-holding module is related to the amplitude of the substrate-holding module and the vibration speed of the substrate-holding module. Furthermore, the vibration speed of the substrate-holding module is related to the flow rate of the electrolyte. It is preferable that the vibration speed of the substrate-holding module is greater than the flow rate of the electrolyte from the center to the edge. Usually, the flow rate of the electrolyte is set to 0.01 m / s to 0.2 m / s, which depends on the initial flow rate of the electrolyte supply. The vibration frequency of the substrate-holding module can be calculated by the following formula:

number

[0026] A vibration model diagram is shown in Fig. 21. The size of the diaphragm 715 can be calculated by combining this model diagram with the following calculation formula.

number

number

number

number

[0027] In formulas (1) to (4), f is the vibration frequency of the substrate holding module, m is the weight of the substrate holding module, k is the rigidity coefficient of the diaphragm, E is the elasticity coefficient of the diaphragm material, H is the cross-sectional width of the diaphragm, B is the cross-sectional height of the diaphragm, and L is the length of the diaphragm.

[0028] The size of diaphragm 715 can be calculated based on formulas (1) to (4). Some examples are shown in the table below. [Table 1]

[0029] 10A to 11B show a plating apparatus for depositing metal on a substrate having a pattern structure according to another exemplary embodiment of the present invention. Compared with the plating apparatus shown in FIGS. 7A to 9B, in this embodiment, the driving device 705' may be a pair of motors or cylinders for resonating with the vibration plate 715 to vibrate the substrate holding module in the horizontal direction. The pair of motors or cylinders may be disposed on the bracket 714 and disposed on both sides of the vibration plate 715, respectively. Alternatively, the pair of motors or cylinders may be disposed on the mounting plate 716 and disposed on both sides of the vibration plate 715, respectively.

[0030] 12A-14B show a plating apparatus for depositing metal on a substrate having a pattern structure according to another embodiment of the present invention. The plating apparatus 1200 includes a plating bath 1201, a substrate holding module, a pair of vibration plates 1215, a mounting plate 1216, a support base 1217, and a drive unit 1205. The substrate holding module further includes a substrate holder 1202, a support column 1212, a fixing device 1213, a bracket 1214, a rotary actuator 1204, a vertical coupling member 1219, a horizontal coupling member 1220, an elastic coupling member 1221, and a frame 1222.

[0031] The plating bath 1201 is configured to contain an electrolyte. The plating bath 1201 may include an anode chamber and a cathode chamber for electroplating. The anode chamber and the cathode chamber are separated by a membrane disposed on a membrane frame. The anode chamber may be divided into a number of anode zones, each of which contains an anode connected to an independently controlled power source. The anode may be made of copper (Cu), titanium (Ti), titanium plate (Pt coated), etc. At least one diffusion plate 1211 having a number of small openings is disposed in the cathode chamber for uniform control of the electric field and uniform control of the electrolyte flow. A groove 1208 is provided around the cathode chamber to receive the electrolyte overflowing from the cathode chamber.

[0032] The substrate holder 1202 is configured to hold a substrate. The support 1212 is connected to the substrate holder 1202 and the fixing device 1213. The bracket 1214 is substantially U-shaped and has a pair of arms and a base. The pair of arms of the bracket 1214 are disposed on both sides of the fixing device 1213 and respectively connected to a pair of vibration plates 1215. The pair of vibration plates 1215 are connected to both sides of the fixing device 1213. The base of the bracket 1214 is connected to a mounting plate 1216. The mounting plate 1216 is disposed on a support base 1217. The mounting plate 1216 is movable up and down along the support base 1217 under the drive of a vertical actuator so as to move the substrate holding module up and down. To prevent sagging of the substrate holding module, the vertical connecting member 1219 is connected to the base of the bracket 1214 and to a horizontal connecting member 1220, which is connected to an elastic connecting member 1221, which is connected to a frame 1222 fixed to the fixing device 1213. The rotation actuator 1204 is disposed on the fixing device 1213 and configured to rotate the substrate holder 1202.

[0033] The driver 1205 is disposed on the fixture 1213 and is configured to drive the substrate-holding module to vibrate vertically or resonate at a natural frequency of the vibrating plate 1215 while the substrate is being plated. See FIGS. 13A-13B and 14A-14B. The driver 1205 may be a vibrator.

[0034] The high frequency vertical movement of the substrate holder 1202 can generate a strong stirring effect in the space between the substrate and the diffusion plate 1211. When the substrate holder 1202 descends at high speed, the liquid pressure in the space rises rapidly, and the electrolyte flows into the pattern structure due to the pressure. Then, the micro-wise liquid flow rate in the pattern structure becomes very fast, and the additive penetrates the pattern structure uniformly, which contributes to solving the problem of bump inclination. On the other hand, when the substrate holder 1202 moves up, the space becomes larger, and the liquid pressure in the space decreases rapidly. Then, the liquid in the micro-pattern structure flows out. The high speed vertical movement causes a sudden change in the liquid pressure. The mass transfer rate in the pattern structure is improved.

[0035] 15A to 16B show a plating apparatus for depositing metal on a substrate having a pattern structure according to another exemplary embodiment of the present invention. Compared with the plating apparatus shown in FIG. 12A to FIG. 14B, in this embodiment, the driving device 1205′ may be a motor or a cylinder for resonating with the vibration plate 1215 to vibrate the substrate holding module in the vertical direction. The motor or the cylinder may be disposed on the horizontal connecting member 1220.

[0036] 17A-17B show a plating apparatus for depositing metal on a substrate having a pattern structure according to another exemplary embodiment of the present invention. The plating apparatus 1700 includes a plating bath 1701, a substrate-holding module, a vibration plate 1715, a mounting plate 1716, a support pedestal 1717, and a vertical actuator. The substrate-holding module further includes a substrate holder 1702, a support post 1712, a fixture 1713, and a rotation actuator 1704.

[0037] The plating bath 1701 is configured to contain an electrolyte. The plating bath 1701 may include an anode chamber and a cathode chamber for electroplating. The anode chamber and the cathode chamber are separated by a membrane disposed on a membrane frame. The anode chamber may be divided into a number of anode zones, each of which contains an anode connected to an independently controlled power source. The anode may be made of copper (Cu), titanium (Ti), titanium plate (Pt coated), etc. At least one diffusion plate 1711 having a number of small openings is disposed in the cathode chamber for uniform control of the electric field and uniform control of the electrolyte flow. A groove 1708 is provided around the cathode chamber to receive the electrolyte overflowing from the cathode chamber.

[0038] The substrate holder 1702 is configured to hold a substrate. The support column 1712 is connected to the substrate holder 1702 and the fixing device 1713. The vibration plate 1715 is connected to the side of the fixing device 1713 and the mounting plate 1716. The mounting plate 1716 is disposed on a support base 1717. The mounting plate 1716 is movable up and down along the support base 1717 under the drive of a vertical actuator so as to move the substrate holding module up and down. The rotation actuator 1704 is disposed on the fixing device 1713 and configured to drive the substrate holder 1702 to rotate.

[0039] In this embodiment, the vertical actuator functions as a drive and is configured to drive the substrate holding module to oscillate or resonate vertically at the natural frequency of the diaphragm 1715 while the substrate is being plated.

[0040] 18A-20C show a plating apparatus for depositing metal on a substrate having a pattern structure according to another exemplary embodiment of the present invention. The plating apparatus 1800 includes a plating bath 1801, a substrate holding module, a first diaphragm 18151, a pair of second diaphragms 18152, a mounting plate 1816, a support base 1817, and a first actuator 1805. The substrate holding module includes a substrate holder 1802, a support column 1812, a fixing device 1813, a bracket 1814, and a rotary actuator 1804.

[0041] The plating bath 1801 is configured to contain an electrolyte. The plating bath 1801 may include an anode chamber and a cathode chamber for electroplating. The anode chamber and the cathode chamber are separated by a membrane disposed on a membrane frame. The anode chamber may be divided into a number of anode zones, each of which contains an anode connected to an independently controlled power source. The anode may be made of copper (Cu), titanium (Ti), titanium plate (Pt coated), etc. At least one diffusion plate 1811 having a number of small openings is disposed in the cathode chamber for uniform control of the electric field and uniform control of the flow of the electrolyte. A groove 1808 is provided around the cathode chamber to receive the electrolyte overflowing from the cathode chamber.

[0042] The substrate holder 1802 is configured to hold a substrate. The support 1812 is connected to the substrate holder 1802 and the fixing device 1813. The bracket 1814 is substantially U-shaped and has a pair of arms and a base. The pair of arms of the bracket 1814 are disposed on both sides of the fixing device 1813 and are respectively connected to a pair of second vibration plates 18152. The pair of second vibration plates 18152 are connected to both sides of the fixing device 1813. The base of the bracket 1814 is connected to one end of the first vibration plate 18151. The other end of the first vibration plate 18151 is connected to a mounting plate 1816. The mounting plate 1816 is disposed on a support base 1817. The mounting plate 1816 is movable up and down along the support base 1817 under the drive of a vertical actuator so as to move the substrate holding module up and down. The rotational actuator 1804 is disposed on the fixture 1813 and is configured to rotate the substrate holder 1802 .

[0043] The first drive device 1805 is disposed on a base portion of the bracket 1814 and is configured to drive the substrate holding module to vibrate in a horizontal direction or to resonate at a natural frequency of the first vibrating plate 18151. The vertical actuator functions as a second drive device and is configured to drive the substrate holding module to vibrate in a vertical direction or to resonate at a natural frequency of the pair of second vibrating plates 18152. In this embodiment, while the substrate is being plated, the substrate holding module may be driven by the first drive device 1805 and the vertical actuator to vibrate horizontally and vertically simultaneously.

[0044] 22 shows a plating apparatus for depositing metal on a substrate having a pattern structure according to another exemplary embodiment of the present invention. The plating apparatus 2200 includes a plating bath 2201, a substrate holding module, a mounting plate 2216, a support base 2217, and a drive unit 2205. The substrate holding module further includes a substrate holder 2202, a support column 2212, a connecting plate 2225, a fixing device 2213, a bracket 2214, a rotary actuator 2204, a shaft 2223, a bearing 2224, and a pair of elastic members 2226.

[0045] The plating bath 2201 is configured to contain an electrolyte. The plating bath 2201 may include an anode chamber and a cathode chamber for electroplating. The anode chamber and the cathode chamber are separated by a membrane disposed on a membrane frame. The anode chamber may be divided into a number of anode zones, each of which contains an anode connected to an independently controlled power source. The anode may be made of copper (Cu), titanium (Ti), titanium plate (Pt coated), etc. At least one diffusion plate 2211 having a number of small openings is disposed in the cathode chamber for uniform control of the electric field and uniform control of the electrolyte flow. A groove 2208 is provided around the cathode chamber to receive the electrolyte overflowing from the cathode chamber.

[0046] The substrate holder 2202 is configured to hold a substrate. The support 2212 is connected to the substrate holder 2202 and the connecting plate 2225. The rotary actuator 2204 is disposed on the fixing device 2213. The shaft 2223 passes through the fixing device 2213. One end of the shaft 2223 is connected to the rotary actuator 2204, and the other end of the shaft 2223 is connected to the connecting plate 2225 via a bearing 2224. A pair of elastic members 2226 are connected to the shaft 2223 and the connecting plate 2225. The bracket 2214 is fixed to a side surface of the fixing device 2213 and connected to the mounting plate 2216. The mounting plate 2216 is disposed on a support base 2217. The mounting plate 2216 is movable up and down along the support base 2217 under the drive of the vertical actuator so as to move the substrate holding module up and down. The driving device 2205 is disposed on the connecting plate 2225.

[0047] During plating, the shaft 2223 rotates at a rotation speed w1 due to the driving of the rotary actuator 2204. Since a pair of elastic members 2226 are connected to the shaft 2223 and the connecting plate 2225, not only the substrate holder 2202 but also the support 2212 and the connecting plate 2225 rotate together with the shaft 2223 at a rotation speed w1. While the substrate holder 2202 rotates for plating, the driving device 2205 drives not only the substrate holder 2202 but also the support 2212 and the connecting plate 2225 to rotate clockwise and counterclockwise at a rotation speed w2. Preferably, the rotation speed w2 is greater than the rotation speed w1. This allows the rotation speed of the substrate holder 2202 to be rapidly changed to achieve stirring of the electrolyte. This can improve the uniformity of plating and the plating speed.

[0048] As described above, the present invention provides a method for improving the uniformity of the plating metal in the microstructures by using at least one actuator to vibrate the substrate while it is immersed in the electrolyte to be plated, thereby distributing the additives in the microstructures uniformly. Furthermore, compared to the prior art, which uses paddles to stir the electrolyte, the present invention has no shelves such as paddles between the substrate and the diffuser, resulting in a more uniform electric field distribution and no "shadow" problem.

[0049] The present invention further provides a plating method for depositing a metal on a substrate having a pattern structure, the plating method comprising the steps of: mounting and holding a substrate on a substrate holding module; immersing the substrate in an electrolyte contained in a plating bath; and driving the substrate holding module together with the substrate to vibrate horizontally and / or vertically while the substrate is immersed in the electrolytic solution and plating is being carried out.

[0050] In one embodiment, the substrate is held horizontally by a substrate support module.

[0051] In one embodiment, the substrate is held vertically by a substrate-holding module, and the substrate-holding module and substrate are immersed vertically in the electrolyte.

[0052] In one embodiment, the electrolyte has a flow rate V2, and the substrate-supporting module and the substrate are driven to vibrate at a vibration velocity V1, where V1≧0.2V2.

[0053] In one embodiment, the vibration frequency of the substrate support module is set to 0.1 Hz to 500 Hz.

[0054] In one embodiment, the amplitude of the substrate holding module is greater than the size of the pattern structure.

[0055] In one embodiment, the amplitude of the substrate holding module is set to 25um to 2000um.

[0056] In one embodiment, the plating method further comprises driving the substrate to rotate while it is immersed in the electrolyte being plated.

[0057] 23 illustrates a plating apparatus for depositing metal on a substrate having a patterned structure according to an exemplary embodiment of the present invention. The plating apparatus 2300 includes a plating bath 2301 configured to contain an electrolyte, a substrate-holding module 2302 configured to hold a substrate 2303 and electrically connect with a conductive surface of the substrate 2303, and a rotary actuator 2304 configured to rotate the substrate-holding module 2302 along an axis of the substrate-holding module 2302. The plating apparatus 2300 further includes a controller 2330 connected to the rotary actuator 2304 and configured to rotate the rotary actuator 2304 N times and then N times the reverse for a number of alternating cycles. N is equal to or less than 3.0. Preferably, N is 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0. The controller 2330 controls the rotation speed of the rotary actuator 2304 to be less than 120 rpm. The plating apparatus 2300 further includes at least one anode 2306 disposed in the plating bath 2301 and facing a conductive surface of the substrate 2303, and a power source 2307 electrically connected to the substrate holding module 2302 and the anode 2306. A groove 2308 is provided around the plating bath 2301 to receive electrolyte overflowing from the plating bath 2301. The plating apparatus 2300 further includes a tank 2310. A pipe 2309 is connected to the groove 2308 and the tank 2310. The tank 2310 is connected to the plating bath 2301 via another pipe 2309.

[0058] In this embodiment, during plating, the controller 2330 is used to rotate the rotary actuator 2304 N (N≦3.0) and then N reverse rotations alternately for a number of cycles. This improves the uniformity of the plated metal in the patterned features. Due to the high frequency of the vibrational motion of the substrate, the electrolyte on the substrate surface changes dramatically during the change in rotation direction. By dramatically changing the rotary actuator from clockwise to counterclockwise, a turbulent state of the liquid can be generated, resulting in strong streaky agitation on the substrate surface. The rotary actuator is controlled in a point-to-point position control mode.

[0059] The present invention further provides a plating method for depositing a metal on a substrate having a pattern structure, the plating method comprising the steps of: mounting and holding a substrate on a substrate holding module; immersing the substrate in an electrolyte contained in a plating bath; driving the substrate holding module together with the substrate by a rotary actuator while the substrate is immersed in the electrolytic solution and plating is being performed; and controlling the rotary actuator to rotate N times (N≦3.0) and then rotate N times in the reverse direction alternately for a number of cycles.

[0060] In one embodiment, N is 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0. When N is 0.5, the substrate-holding module rotates from 0 degrees to 180 degrees, and then rotates in the opposite direction. The rotation speed is the same, and the frequency is very high. If the substrate-holding module rotates less than 180 degrees, the plating speed of the substrate surface becomes asymmetric. Therefore, the rotation period should be 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0. When N is greater than 3.0, for example, at a rotation speed of 60 rpm, it takes 3 seconds to rotate clockwise and 3 seconds to rotate counterclockwise. One period takes 6 seconds. The larger N is, the longer the period, and the weaker the stirring effect caused by the dramatic change described above.

[0061] In one embodiment, the rotational speed of the rotary actuator is controlled to less than 120 rpm.

[0062] Any of the above-described embodiments of the present invention are suitable for electroless plating to obtain uniform metal deposition in patterned structures on a substrate.

[0063] Any of the above-described embodiments of the present invention are also suitable for electrically removing metal on a substrate to obtain a uniform topography.

[0064] The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form set forth above. Obviously, many modifications and variations are possible in light of the above teachings. Modifications and variations obvious to those skilled in the art are included within the scope of the present invention as defined in the appended claims.

Claims

1. A plating apparatus for depositing a metal on a substrate having a pattern structure, the plating apparatus comprising: a plating bath configured to contain an electrolytic solution; a substrate holding module configured to hold a substrate; a rotary actuator configured to drive the substrate holding module in rotation together with the substrate; and a controller configured to alternately rotate the rotary actuator N (N≦3.0) times and then N reversely rotate the rotary actuator for a number of cycles.

2. 2. The plating apparatus of claim 1, wherein N is 0.5, 1.0, 1.5, 2.0, 2.5, and 3.

0.

3. 2. The plating apparatus of claim 1, wherein the rotational speed of the rotary actuator is less than 120 rpm.

4. A plating method for depositing a metal on a substrate having a pattern structure, comprising the steps of: mounting and holding the substrate on a substrate holding module; immersing the substrate in an electrolyte contained in a plating bath; rotating the substrate holding module together with the substrate by a rotary actuator while plating is being performed with the substrate immersed in the electrolyte; and controlling the rotary actuator to rotate N (N≦3.0) times and then rotate N times in the reverse direction alternately for a number of cycles.

5. 5. The plating method of claim 4, wherein N is 0.5, 1.0, 1.5, 2.0, 2.5, or 3.

0.

6. 5. The plating method according to claim 4, wherein the rotational speed of the rotary actuator is less than 120 rpm.

7. 1. A plating apparatus for depositing metal on a substrate having a pattern structure, comprising: a plating bath configured to contain an electrolyte solution, a substrate-holding module configured to hold a substrate, at least one drive device configured to drive the substrate-holding module together with the substrate to vibrate horizontally and / or vertically while the substrate is immersed in the electrolyte solution to be plated, and at least one vibration plate, the at least one driver is configured to drive the substrate-holding module to resonate at a natural frequency of the at least one diaphragm; The at least one vibration plate is connected to the substrate holding module.

8. The plating apparatus according to claim 7 , wherein the at least one driving device is one of a motor, a cylinder, and a vibrator.

9. The plating apparatus of claim 7 , wherein the substrate holding module holds the substrate horizontally.

10. The plating apparatus according to claim 7 , wherein the substrate holding module holds the substrate vertically, and the substrate holding module and the substrate are vertically immersed in the electrolytic solution.

11. 8. The plating apparatus of claim 7, wherein the electrolyte has a flow rate V2, and the at least one driving device drives the substrate holding module and vibrates the substrate at a vibration velocity V1, where V1≧0.2V2.

12. 8. The plating apparatus of claim 7, further comprising a mounting plate and a support base, the substrate holding module further having a bracket, one end of the vibration plate being connected to the bracket and the other end of the vibration plate being connected to the mounting plate, the mounting plate being disposed on the support base.

13. The plating apparatus according to claim 12 , wherein the mounting plate is movable up and down along the support base.

14. 13. The plating apparatus of claim 12, wherein the actuator is disposed on the bracket, the actuator being a vibrator.

15. 13. The plating apparatus of claim 12, further comprising a pair of limit stop members configured to limit an amplitude of the substrate-holding module while the substrate-holding module is driven to oscillate.

16. 16. The plating apparatus of claim 15, wherein the pair of limit stop members are disposed on the bracket and positioned on either side of the diaphragm, or the pair of limit stop members are disposed on the mounting plate and positioned on either side of the diaphragm.

17. The plating apparatus of claim 12, wherein the driving device is a pair of motors or cylinders, the pair of motors or cylinders being arranged on the bracket and respectively disposed on both sides of the vibration plate, or the pair of motors or cylinders being arranged on the mounting plate and respectively disposed on both sides of the vibration plate.

18. 8. The plating apparatus of claim 7, further comprising a mounting plate and a support base, the substrate holding module further comprising a fixing device and a bracket, the at least one vibration plate includes a pair of vibration plates, the bracket has a pair of arms and a base portion, the pair of arms of the bracket are disposed on either side of the fixing device and respectively connected to the pair of vibration plates, the pair of vibration plates are connected to either side of the fixing device, the base portion of the bracket is connected to the mounting plate, and the mounting plate is disposed on the support base.

19. The plating apparatus according to claim 18 , wherein the mounting plate is movable up and down along the support base.

20. 20. The plating apparatus of claim 18, wherein the substrate holding module further comprises a vertical connecting member, a horizontal connecting member, an elastic connecting member and a frame, the vertical connecting member being connected to the base portion of the bracket and the horizontal connecting member, the horizontal connecting member being connected to the elastic connecting member, the elastic connecting member being connected to the frame, and the frame being fixed to the fixing device.

21. 20. The plating apparatus of claim 18, wherein the driving device is a vibrator disposed on the stationary device.

22. 21. The plating apparatus of claim 20, wherein the drive device is a motor or a cylinder disposed on the horizontal connecting member.

23. 8. The plating apparatus of claim 7, further comprising a mounting plate and a support base, the substrate holding module further having a fixing device, the vibration plate being connected to the fixing device and a side of the mounting plate, the mounting plate being disposed on the support base, and the drive device being a vertical actuator that moves the mounting plate up and down along the support base to vibrate the substrate holding module in a vertical direction.

24. 8. The plating apparatus of claim 7, wherein the at least one vibration plate includes a first vibration plate and a pair of second vibration plates, and the at least one drive unit includes a first drive unit and a second drive unit, the first drive unit configured to drive the substrate holding module to resonate in a horizontal direction at a natural frequency of the first vibration plate, and the second drive unit configured to drive the substrate holding module to resonate in a vertical direction at a natural frequency of the pair of second vibration plates.

25. 25. The plating apparatus of claim 24, wherein the second drive device is a vertical actuator.

26. The plating apparatus of claim 7 , further comprising a rotational actuator configured to drive the substrate in rotation.

27. 8. The plating apparatus according to claim 7, wherein the vibration frequency of the substrate holding module is set to 0.1 Hz to 500 Hz.

28. The plating apparatus according to claim 7 , wherein the amplitude of the substrate holding module is greater than a size of the pattern structure of the substrate.

29. 8. The plating apparatus according to claim 7, wherein the amplitude of the substrate holding module is set to 25 um to 2000 um.

30. 8. The plating apparatus of claim 7, wherein the substrate holding module further comprises a substrate holder fixed to a connecting plate, a rotary actuator, a shaft, a bearing, and a pair of elastic members, the substrate holder being configured to hold the substrate, one end of the shaft being connected to the rotary actuator and the other end of the shaft being connected to the connecting plate via the bearing, the pair of elastic members being connected to the shaft and the connecting plate, the rotary actuator rotatingly drives the shaft to rotate the substrate holder at a rotational speed w1, and while the substrate holder rotates for plating, the drive device alternately rotates the substrate holder clockwise and counterclockwise at a rotational speed w2.

31. 31. The plating apparatus of claim 30, wherein the rotation speed w2 is greater than the rotation speed w1.

32. 1. A plating method for depositing a metal on a substrate having a pattern structure, comprising the steps of: a step of mounting and holding the substrate on a substrate holding module connected to a diaphragm; immersing the substrate in an electrolyte contained in a plating bath; Driving the substrate holding module to resonate at a natural frequency of the diaphragm in a horizontal direction while the substrate is immersed in the electrolyte and plating is being performed; and / or driving the substrate holding module to resonate at a natural frequency of the diaphragm in a vertical direction while the substrate is immersed in the electrolytic solution and plating is being performed; The plating method comprises:

33. The plating method of claim 32 , wherein the substrate is held horizontally by the substrate holding module.

34. The plating method according to claim 32 , wherein the substrate is held vertically by the substrate holding module, and the substrate holding module and the substrate are vertically immersed in the electrolytic solution.

35. 33. The plating method of claim 32, wherein the electrolyte has a flow rate V2, and the substrate holding module and the substrate are driven to vibrate at a vibration velocity V1 (V1 ≥ 0.2V2).

36. 33. The plating method according to claim 32, wherein the vibration frequency of the substrate holding module is set to 0.1 Hz to 500 Hz.

37. 33. The plating method of claim 32, wherein the amplitude of the substrate holding module is greater than a size of the pattern structure of the substrate.

38. The plating method according to claim 32, wherein the amplitude of the substrate holding module is set to 25 um to 2000 um.

39. 33. The plating method of claim 32, further comprising driving the substrate in rotation while it is immersed in the electrolyte being plated.

Images