Electroplating jig and electroplating apparatus

Abstract

The application discloses an electroplating clamp and an electroplating device, and relates to the technical field of semiconductor devices. The electroplating clamp comprises a clamping mechanism and a driving mechanism. The clamping mechanism comprises a clamping base and a clamping pressing plate which is arranged in a lifting manner relative to the clamping base. The driving mechanism comprises a cylinder and a piston. The cylinder has a closed hollow chamber, and the bottom of the cylinder is fixedly connected with the clamping pressing plate. The piston is fixedly arranged in the hollow chamber, and the hollow chamber is divided into a closed first cavity and a second cavity. The first cavity is located below the second cavity. When the pressure inside the first cavity is greater than the pressure inside the second cavity, the cylinder drives the clamping pressing plate to move downwards, and a wafer fixedly arranged at the bottom of the clamping base is pressed. When the pressure inside the first cavity is less than the pressure inside the second cavity, the cylinder drives the clamping pressing plate to move upwards, and the wafer fixedly arranged at the bottom of the clamping base is released upwards. The electroplating clamp simplifies the mechanical structure, reduces the space occupation, and greatly improves the stability of wafer rotation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor equipment, in particular to a kind of electroplating fixture and electroplating equipment. BACKGROUND

[0002] In the semiconductor wafer manufacturing process, electroplating is an important process step to form metal interconnection layer, bump, rewiring layer and other key structures. As the core component of electroplating equipment, the main function of electroplating fixture is to reliably clamp the wafer and accurately immerse it in the electroplating solution in the electroplating tank. At the same time, the wafer often needs to be driven to rotate or tilt during electroplating to achieve uniformity and specific morphology control of the plated layer.

[0003] The existing wafer clamping mechanism usually adopts independent lifting drive device. These drive devices often need additional transmission components to transmit driving force to the clamping pressure plate, resulting in complex overall structure of the fixture, large volume, especially when the rotating function needs to be integrated, the arrangement space of the lifting drive device is limited, which increases the difficulty of fixture design, and there is a problem of insufficient compactness. When the fixture needs to drive the wafer to rotate to improve the uniformity of electroplating, if the traditional lifting drive device (such as the piston rod of the air cylinder) needs to rotate with the clamping mechanism, the dynamic balance is difficult to guarantee, which is easy to cause vibration and noise, affecting the stability of wafer rotation. SUMMARY

[0004] The purpose of the present application is to provide an electroplating fixture and electroplating equipment, which not only has simple and compact structure, reduces the occupied space, but also can reduce vibration and noise during wafer rotation, and ensure the stability of wafer rotation.

[0005] To achieve this purpose, the following technical solutions are adopted in the present application:

[0006] An electroplating fixture, comprising:

[0007] A clamping mechanism, comprising a clamping base and a clamping pressure plate which is arranged in a lifting manner relative to the clamping base;

[0008] A drive mechanism, comprising a cylinder and a piston, the cylinder has a closed hollow chamber, and the bottom of the cylinder is fixedly connected with the clamping pressure plate; the piston is fixedly arranged in the hollow chamber, which divides the hollow chamber into a closed first cavity and a second cavity, and the first cavity is located below the second cavity;

[0009] When the pressure inside the first cavity is greater than the pressure inside the second cavity, the cylinder drives the clamping pressure plate to move downward, and the wafer fixedly arranged at the bottom of the clamping base is pressed upward; when the pressure inside the first cavity is less than the pressure inside the second cavity, the cylinder drives the clamping pressure plate to move upward, and the wafer fixedly arranged at the bottom of the clamping base is released upward.

[0010] As an optional solution of the electroplating fixture, the cylinder body comprises a side wall and a top wall and a bottom wall connected with the side wall, the side wall, the top wall and the bottom wall form the hollow chamber, and the bottom wall is fixedly connected with the upper part of the clamping platen.

[0011] As an optional solution of the electroplating fixture, the cylinder body comprises a side wall and a top wall connected with the side wall, the side wall is externally provided with a sealing plate, the sealing plate is sealingly and fixedly connected with the upper surface of the clamping platen, so that the side wall, the top wall, the sealing plate and the part of the upper surface of the clamping platen form the hollow chamber.

[0012] As an optional solution of the electroplating fixture, the circumferential wall of the piston is spaced apart to provide a sealing groove, the sealing groove is embedded with a first sealing ring, the first sealing ring seals the upper part of the first cavity and the lower part of the second cavity, so that the first cavity and the second cavity are in a sealed state.

[0013] As an optional solution of the electroplating fixture, the driving mechanism further comprises a pneumatic shaft, a gas source and a pneumatic electromagnetic valve, the pneumatic shaft passes through the second cavity and is connected with the piston; the pneumatic shaft has a first gas channel and a second gas channel therein, the first gas channel is in communication with the first cavity, and the second gas channel is in communication with the second cavity.

[0014] The pneumatic electromagnetic valve is used to control the gas source to selectively supply gas to the first gas channel or the second gas channel.

[0015] As an optional solution of the electroplating fixture, the pneumatic electromagnetic valve is a two-position five-way electromagnetic valve, the two-position five-way electromagnetic valve comprises an air inlet, a down pressure control interface, a return control interface, a first exhaust interface and a second exhaust interface, the air inlet is connected with the gas source, the down pressure control interface is in communication with the first gas channel, and the first exhaust interface is in communication with a first exhaust passage; the return control interface is in communication with the second gas channel, and the second exhaust interface is in communication with a second exhaust passage.

[0016] As an optional solution of the electroplating fixture, the pneumatic shaft has a first hole and a second hole arranged concentrically, the first hole is located in the middle of the second hole and penetrates through the end of the pneumatic shaft away from the gas source, forming the first gas channel.

[0017] Both ends of the second hole are blocked, a plurality of air inlet holes are uniformly distributed at one blocked end of the second hole, and a plurality of air outlet holes are uniformly distributed at the other blocked end, the plurality of air inlet holes, the second hole and the plurality of air outlet holes form the second gas channel.

[0018] As an optional solution of the electroplating clamp, the electroplating clamp further comprises a guide cylinder, the guide cylinder is sleeved outside the pneumatic shaft, one end of the guide cylinder is fixed with the pneumatic shaft, and the other end is fixed with the clamping base.

[0019] The cylinder body is slidably arranged in the guide cylinder.

[0020] As an optional solution of the electroplating clamp, the inner wall of the guide cylinder is provided with a bushing, and the cylinder body is in sliding fit with the bushing.

[0021] As an optional solution of the electroplating clamp, the bushing is made of copper alloy material and inlaid with a graphite body.

[0022] As an optional solution of the electroplating clamp, the driving mechanism further comprises a rotary motor connected with the pneumatic shaft, and the rotary motor is configured to drive the clamping mechanism to rotate through the pneumatic shaft.

[0023] As an optional solution of the electroplating clamp, the rotary motor is a hollow rotary motor, the pneumatic shaft passes through the center cavity of the hollow rotary motor and is connected with the piston, and the rotor of the hollow rotary motor is connected with the pneumatic shaft through a shaft coupling.

[0024] As an optional solution of the electroplating clamp, the driving mechanism further comprises a rotary air joint, the rotary air joint is connected with the end of the pneumatic shaft away from the piston, and the pneumatic electromagnetic valve is selectively communicated with the first air channel or the second air channel through the rotary air joint.

[0025] As an optional solution of the electroplating clamp, the electroplating clamp further comprises a control unit, the control unit is electrically connected with the pneumatic electromagnetic valve and the rotary motor respectively;

[0026] The control unit is configured to: in response to a wafer clamping and rotating instruction, control the pneumatic electromagnetic valve to supply the gas source to the first air channel, drive the clamping pressure plate to press down the wafer fixed at the bottom of the clamping base, and control the rotary motor to start and drive the clamping mechanism to rotate at a constant speed.

[0027] The control unit is further configured to: in response to a wafer stopping rotating and releasing instruction, control the rotary motor to stop driving, and control the pneumatic electromagnetic valve to supply the gas source to the second air channel, drive the clamping pressure plate to loosen the wafer at the bottom of the clamping base upwards.

[0028] As an optional solution of the electroplating clamp, the electroplating clamp further comprises an inclination motor for driving the electroplating clamp to incline, so that the wafer fixed by the electroplating clamp inclines synchronously, and the inclination angle is less than 30 degrees.

[0029] An electroplating apparatus comprises an electroplating cavity and an electroplating clamp arranged above the electroplating cavity, the electroplating clamp being capable of clamping a wafer and carrying the wafer to the electroplating cavity to perform an electroplating process, the electroplating clamp being the electroplating clamp according to any one of the preceding solutions.

[0030] The present application has the following advantages:

[0031] The electroplating clamp provided by the present application comprises a clamping mechanism and a driving mechanism. The clamping mechanism comprises a clamping base and a clamping pressing plate, and the clamping pressing plate is arranged to be liftable relative to the clamping base. The driving mechanism comprises a cylinder and a piston. The cylinder has a closed hollow chamber, and the piston is fixedly arranged in the hollow chamber to divide the hollow chamber into a closed first cavity and a second cavity. The first cavity is located below the second cavity. The bottom of the cylinder is fixedly connected with the clamping pressing plate. When the internal pressure of the first cavity is greater than the internal pressure of the second cavity, the cylinder drives the clamping pressing plate to move downward to press a wafer fixed on the bottom of the clamping base. The bottom of the cylinder is rigidly connected with the clamping pressing plate. Compared with the prior art in which a piston rod is connected with the clamping pressing plate, the driving force of the gas pressure is directly converted into the lifting movement of the clamping pressing plate. The structure is compact, and the pneumatic force transmission is direct and efficient. The piston rod and its connecting structure are omitted, the mechanical structure is significantly simplified, and the space occupation is reduced. The driving force generated by the gas pressure is directly generated on the cylinder and transmitted to the clamping pressing plate with zero distance, avoiding the friction, gap and deformation loss in the force transmission path of the traditional piston rod, and realizing efficient and non-lagging transmission of the force. The driving force is applied to the clamping pressing plate through the large area and rigidity of the bottom of the cylinder, which can better resist the centrifugal force generated by rotation and other disturbances, so that the electroplating clamp can significantly reduce the vibration and noise level in the high-speed rotating state, the lifting movement of the clamping pressing plate is more stable and smooth, and the stability of wafer rotation is greatly improved.

[0032] The electroplating apparatus provided by the present application clamps a wafer by using the electroplating clamp and carries the wafer to the electroplating cavity to perform an electroplating process. The structure of the electroplating clamp is compact, the path of the pneumatic driving force to the clamping pressing plate is the shortest, the efficiency is the highest, and the response is the fastest. The stability of wafer rotation is ensured, and then the uniformity of the electroplating liquid flow field on the wafer surface is ensured, and the electroplating quality of the wafer is improved. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a structural schematic diagram of the electroplating clamp provided by the present application;

[0034] Figure 2 is a sectional view of the electroplating clamp provided by the present application;

[0035] Figure 3 Figure 7 is a schematic diagram of the state of the driving mechanism of the electroplating clamp driving the clamping presser plate to descend to the lowest position provided by the embodiment of the present application;

[0036] Figure 4 Figure 8 is a schematic diagram of the state of the driving mechanism of the electroplating clamp driving the clamping presser plate to ascend to the highest position provided by the embodiment of the present application;

[0037] Figure 5 Figure 9 is a sectional view of the cooperation between the driving mechanism and the clamping mechanism provided by the embodiment of the present application;

[0038] Figure 6 Figure 10 is a sectional view of the guide cylinder provided by the embodiment of the present application;

[0039] Figure 7 Figure 11 is a structural schematic diagram of the piston provided by the embodiment of the present application;

[0040] Figure 8 Figure 12 is a structural schematic diagram of the connection between the rotary air joint and the pneumatic shaft provided by the embodiment of the present application;

[0041] Figure 9 Figure 13 is a sectional view of the A-A direction in Figure 12; Figure 8

[0042] Figure 14 is a sectional view of the B-B direction in Figure 12. Figure 10 Figure 9

[0043] Figure 1 is a schematic diagram of the electroplating clamp provided by the embodiment of the present application;

[0044] 1. clamping mechanism; 11. clamping base; 111. base plate; 1111. wafer positioning cavity; 112. connecting frame; 1121. top frame; 1122. guide column; 12. clamping presser plate; 121. presser plate body; 122. connecting plate;

[0045] 2. driving mechanism; 21. cylinder body; 211. first cavity; 212. second cavity; 22. piston; 221. sealing groove; 222. connecting hole; 23. sealing plate; 24. pneumatic shaft; 241. first hole; 242. second hole; 243. air inlet hole; 244. air outlet hole; 245. stepped ring; 25. pneumatic electromagnetic valve; 26. rotary air joint; 27. connecting ring; 28. rotary motor;

[0046] 3. coupling;

[0047] 4. guide cylinder; 41. flange plate; 42. connecting end; 421. through hole;

[0048] 5. bushing;

[0049] ​​61, first sealing ring; 62, second sealing ring; 63, third sealing ring; 64, fourth sealing ring; 65, fifth sealing ring; 66, sixth sealing ring. DETAILED DESCRIPTION

[0050] Embodiments of the present application are described in detail below with reference to the attached drawing figures, wherein the same or like reference numerals and characters throughout the figures denote the same or like elements or components. The embodiments described below are exemplary and are intended to provide examples of the present application, and are not intended to limit the present application.

[0051] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0052] Unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" should be understood broadly, for example, it can be fixedly connected, or it can be detachably 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; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0053] Unless otherwise explicitly specified and limited, "on" or "under" the first feature of the second feature can include that the first feature and the second feature are in direct contact, or that the first feature and the second feature are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "above" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is higher in horizontal height than the second feature. The first feature "below", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the first feature is lower in horizontal height than the second feature.

[0054] The technical solutions of the present application are further illustrated below in conjunction with the drawings and through specific embodiments.

[0055] As a core component of electroplating equipment, the main function of the electroplating clamp is to reliably clamp the wafer and accurately immerse it in the electroplating solution in the electroplating tank. At the same time, the wafer needs to be driven to rotate or tilt during the electroplating process to achieve uniformity and specific morphology control of the plated layer.

[0056] As shown in Figure 1 , the electroplating clamp includes a clamping mechanism 1 and a driving mechanism 2. The clamping mechanism 1 includes a clamping base 11 and a clamping pressing plate 12 that is arranged to be liftable relative to the clamping base 11. The wafer is transferred to the clamping base 11 by a mechanical hand. The driving mechanism 2 drives the clamping pressing plate 12 to descend, thereby fixing the wafer at the bottom of the clamping base 11. The clamping base 11 immerses the surface of the wafer to be electroplated in the electroplating solution. Subsequently, the driving mechanism 2 drives the clamping mechanism 1 to rotate the wafer at a uniform speed, so that the wafer surface is in full contact with the electroplating solution to ensure the uniformity of the plated layer on the wafer surface. After the electroplating is completed, the electroplating clamp is raised, and the wafer is separated from the electroplating solution. The driving mechanism 2 drives the clamping pressing plate 12 to rise, thereby releasing the wafer at the bottom of the clamping base 11 upward, so that the mechanical hand can take away the wafer with completed electroplating from the clamping base 11.

[0057] The existing driving mechanism uses the piston rod of a cylinder to drive the clamping pressing plate to lift and lower. The driving force is transmitted to the clamping pressing plate through the piston rod, resulting in a complex overall structure of the electroplating clamp and a large volume. In particular, when the rotation function needs to be integrated, the lifting arrangement space is limited, which increases the difficulty of electroplating clamp design and causes the problem of insufficient compactness. When the driving mechanism drives the clamping mechanism to rotate, the piston rod of the cylinder rotates together with the clamping mechanism. The dynamic balance is difficult to guarantee, which easily causes vibration and noise, affecting the stability of wafer rotation.

[0058] To solve the above technical problems, the electroplating clamp provided by the embodiment, as shown in Figure 2 , the driving mechanism 2 includes a cylinder body 21 and a piston 22. The cylinder body 21 has a closed hollow chamber, and the bottom of the cylinder body 21 is fixedly connected with the clamping pressing plate 12. The piston 22 is fixedly arranged in the hollow chamber, thereby dividing the hollow chamber into a closed first cavity 211 and a second cavity 212. The first cavity 211 is located below the second cavity 212. When the pressure inside the first cavity 211 is greater than the pressure inside the second cavity 212, the cylinder body 21 drives the clamping pressing plate 12 to move downward, thereby fixing the wafer at the bottom of the clamping base 11. When the pressure inside the first cavity 211 is less than the pressure inside the second cavity 212, the cylinder body 21 drives the clamping pressing plate 12 to move upward, thereby releasing the wafer at the bottom of the clamping base 11 upward.

[0059] The driving mechanism 2 rigidly connects the bottom of the cylinder 21 with the clamping pressure plate 12, and converts the driving force of the gas pressure into the lifting movement of the clamping pressure plate 12 directly, which is more compact, and the transmission of the gas power is direct and efficient. The piston rod and its connecting structure are omitted, which significantly simplifies the mechanical structure and reduces the space occupation. The driving force generated by the gas pressure is directly generated on the cylinder 21 and transmitted to the clamping pressure plate 12 with zero distance, avoiding the friction, gap and deformation loss in the transmission path of the traditional piston rod, and realizing the efficient and non-lagging transmission of the force. The driving force is applied to the clamping pressure plate 12 through the large area and rigidity of the bottom of the cylinder 21, which can better resist the centrifugal force generated by rotation and other disturbances, so that the electroplating clamp can significantly reduce the vibration and noise level in the high-speed rotating state, and the lifting movement of the clamping pressure plate 12 is more stable and smooth, which greatly improves the stability of the wafer rotation.

[0060] In an embodiment, continuing to refer to Figures 1-4 The clamping base 11 includes a bottom plate 111 and a connecting frame 112. The bottom plate 111 is provided with a wafer positioning cavity 1111 at the bottom for placing the wafer. The connecting frame 112 includes a top frame 1121 and two guide columns 1122. The guide columns 1122 are symmetrically fixed on opposite sides of the top frame 1121 and fixedly connect the bottom plate 111 and the top frame 1121. The clamping pressure plate 12 includes a pressure plate body 121 and two connecting plates 122 symmetrically arranged on both sides of the pressure plate body 121. The pressure plate body 121 is shaped to match the wafer positioning cavity 1111, ensuring that it can completely cover and press the wafer when pressed down. The two connecting plates 122 are each provided with a through hole, and the guide columns 1122 pass through the through holes of the corresponding connecting plates 122 to form a precise fit, so that the clamping pressure plate 12 can slide along the guide columns 1122, thereby realizing the lifting relative to the clamping base 11.

[0061] In an embodiment, the cylinder 21 includes a side wall, a top wall and a bottom wall connected to the side wall. The side wall, the top wall and the bottom wall form a hollow chamber, and the bottom wall is fixedly connected to the upper part of the clamping pressure plate 12. The top wall and the bottom wall close the two ends of the side wall to form a closed hollow chamber. The bottom of the cylinder 21 is fixedly connected by welding or bolt connection.

[0062] In an embodiment, the cylinder 21 comprises a side wall and a top wall connected with the side wall, and a sealing plate 23 is arranged outside the side wall in extension, and the sealing plate 23 is sealingly and fixedly connected with the upper surface of the clamping pressing plate 12, so that the side wall, the top wall, the sealing plate 23 and the part of the upper surface of the corresponding clamping pressing plate 12 form a hollow chamber. In this way, the part of the upper surface of the clamping pressing plate 12 serves as the cavity wall of the first cavity 211, and the air pressure of the first cavity 211 directly acts on the effective acting surface of the clamping pressing plate 12, eliminating the energy loss of the transmission member such as the piston rod in the traditional mechanical transmission; the air pressure change is instantaneously conducted to the clamping pressing plate 12 through the gas; and the force is efficiently and non-laggingly transmitted. At the same time, the air pressure uniformly covers the acting area of the clamping pressing plate 12 in the form of surface load, overcoming the risk of local stress concentration of the wafer caused by point pressure. The structure directly converts the air pressure energy into the vertical downward pressure of the clamping pressing plate 12, ensuring the uniform stress of the wafer and significantly improving the response speed and energy transmission efficiency of the electroplating clamp.

[0063] Exemplarily, the top of the pressing plate body 121 is provided with a sealing concave cavity, the sealing plate 23 is arranged in the sealing concave cavity and is fixed with the sealing concave cavity by means of fastening bolts or the like; and a second sealing ring 62 is arranged between the sealing plate 23 and the bottom of the sealing concave cavity to ensure the sealing property of the hollow chamber of the cylinder 21.

[0064] In an embodiment, the driving mechanism 2 further comprises a pneumatic shaft 24, a gas source and a pneumatic electromagnetic valve 25, the pneumatic shaft 24 is connected with the piston 22 through the second cavity 212; the pneumatic shaft 24 has a first gas channel and a second gas channel therein, the first gas channel is in communication with the first cavity 211, and the second gas channel is in communication with the second cavity 212. The pneumatic electromagnetic valve 25 is used to control the gas source to selectively supply gas to the first gas channel or the second gas channel. When the pneumatic electromagnetic valve 25 controls the gas source to supply gas to the first gas channel, the gas provided by the gas source enters the first cavity 211 through the first gas channel, and the gas pressure in the first cavity 211 gradually increases, when the pressure inside the first cavity 211 is greater than the pressure inside the second cavity 212, the cylinder 21 starts to move downward, and in turn drives the clamping pressing plate 12 to move downward to fix the wafer located at the bottom of the clamping base 11 by downward pressure. When the pneumatic electromagnetic valve 25 controls the gas source to supply gas to the second gas channel, the gas provided by the gas source enters the second cavity 212 through the second gas channel, and the gas pressure in the second cavity 212 gradually increases, when the pressure inside the second cavity 212 is greater than the pressure inside the first cavity 211, the cylinder 21 starts to move upward, and in turn drives the clamping pressing plate 12 to move upward to release the wafer located at the bottom of the clamping base 11 upward.

[0065] The driving mechanism 2 of the driving cylinder 21 is controlled by the double air channel pneumatic shaft 24 and the pneumatic electromagnetic valve 25, and realizes the bidirectional precise driving of the clamping pressing plate 12. The independent first air channel and the second air channel in the pneumatic shaft 24 are directly connected with the first cavity 211 and the second cavity 212 respectively, and cooperate with the quick reversing of the pneumatic electromagnetic valve 25, so that the pneumatic power can directly act on both sides of the piston 22 without mechanical conversion, thereby improving the driving efficiency. The gas directly reaches the chamber through the air channel, the pressure building rate is high, the pressure difference between the two cavities is used to drive the cylinder 21 to move, the inertia lag is eliminated, and the switching rate is improved. The first cavity 211 is pressurized to form a one-way thrust, so that the clamping pressing plate 12 vertically moves downward, and the wafer offset caused by the inclination is avoided. The second cavity 212 reversely applies pressure to realize active lifting, the gravity reset speed is improved, and the friction damage to the wafer surface is reduced.

[0066] As shown in the example, Figures 5-7 The piston 22 is rigidly fixed to the pneumatic shaft 24, and only the cylinder 21 moves up and down under the driving of the pneumatic pressure, and the piston 22 is static. The peripheral wall of the piston 22 is provided with two sealing grooves 221, and the first sealing ring 61 is embedded in the sealing groove 221. The first sealing ring 61 seals the upper part of the first cavity 211 and the lower part of the second cavity 212, so that the first cavity 211 and the second cavity 212 are in a sealed state. The top wall of the cylinder 21 is processed with a stepped hole, the pneumatic shaft 24 is connected with the stepped hole through the connecting ring 27, two third sealing rings 63 are arranged between the inner wall of the connecting ring 27 and the outer wall of the pneumatic shaft 24, and the fourth sealing ring 64 is arranged between the outer wall of the connecting ring 27 and the inner wall of the small diameter hole of the stepped hole close to the second cavity 212, for blocking the gas leakage of the second cavity 212. The connecting ring 27 is screwed and locked with the stepped hole by means of fastening screws or the like, so as to ensure the coaxiality of the cylinder 21 and the pneumatic shaft 24. The connecting hole 222 is arranged at the center of the piston 22, the pneumatic shaft 24 is press-fitted into the connecting hole 222, the fifth sealing ring 65 is embedded in the hole wall, and the static high pressure sealing between the piston 22 and the pneumatic shaft 24 is realized.

[0067] In an embodiment, the pneumatic electromagnetic valve 25 is a two-position five-way electromagnetic valve, which includes an air inlet, a lower pressure control interface, a return control interface, a first exhaust interface and a second exhaust interface. The air inlet is connected with the gas source, the lower pressure control interface is in communication with the first air channel, and the first exhaust interface is in communication with the first exhaust channel; the return control interface is in communication with the second air channel, and the second exhaust interface is in communication with the second exhaust channel.

[0068] Exemplarily, the air inlet of the two-position five-way electromagnetic valve is directly connected to the air source as a total air inlet, the lower pressing control interface is connected to the first air channel, and the first exhaust interface is communicated with the first exhaust channel; the return control interface is connected to the second air channel, and the second exhaust interface is communicated with the second exhaust channel. The displacement of the valve core is controlled by the on / off of the electromagnetic coil, the air path is switched, and the pressure of the double cavities is reversely driven. When the two-position five-way electromagnetic valve is powered on, the gas provided by the air source enters the first cavity 211 through the air inlet of the two-position five-way electromagnetic valve, the lower pressing control interface, and the first air channel; at the same time, the gas in the second cavity 212 enters the return control interface through the second air channel, and is discharged to the outside through the second exhaust interface and the second exhaust channel. When the two-position five-way electromagnetic valve is powered off, the gas of the air source enters the second cavity 212 through the air inlet of the two-position five-way electromagnetic valve, the return control interface, and the second air channel; at the same time, the gas in the first cavity 211 is discharged to the outside through the first exhaust interface and the first exhaust channel.

[0069] In an embodiment, as shown in Figures 8-10 The pneumatic shaft 24 has a first hole 241 and a second hole 242 arranged concentrically, the first hole 241 is located in the middle of the second hole 242 and penetrates through one end of the pneumatic shaft 24 away from the air source, forming a first air channel. Both ends of the second hole 242 are blocked, a plurality of air inlet holes 243 are uniformly distributed at one blocked end of the second hole 242, and a plurality of air outlet holes 244 are uniformly distributed at the other blocked end, and the plurality of air inlet holes 243, the second hole 242 and the plurality of air outlet holes 244 form a second air channel.

[0070] The pneumatic shaft 24 is arranged as a concentric double-hole structure, the first hole 241 is directly penetrated through the distal end of the pneumatic shaft 24 and communicated with the first cavity 211 as a first air channel, realizing the shortest air path. The second hole 242 forms a ring-shaped second air channel by axial blocking and radial hole opening, which saves more space than the parallel double-tube scheme under the same shaft diameter, meeting the compactness requirement.

[0071] The air inlet end of the second hole 242 is uniformly distributed with a plurality of air inlet holes 243, the gas enters uniformly along the circumferential direction of the annular cavity, forming a rotational flow pressure stabilization layer, and eliminating pressure pulsation. The air outlet end is uniformly distributed with a plurality of air outlet holes 244, the gas is uniformly output along the radial direction, so that the pressure distribution in the second cavity 212 is uniform, and the cylinder body 21 is prevented from being stuck due to unbalanced load.

[0072] The concentric structure completely isolates the first air channel and the second air channel through the solid wall, and prevents the mutual penetration of the gases in the double cavities. The two ends of the second hole 242 are blocked to form a closed pressure-bearing ring, so that the bending stiffness of the pneumatic shaft 24 is improved, and the risk of sealing failure caused by micro-deformation of the shaft under high pressure is suppressed.

[0073] In an embodiment, continuing to refer to Figure 5 and Figure 6The electroplating clamp further comprises a guide cylinder 4 sleeved on the pneumatic shaft 24 and fixed at one end to the pneumatic shaft 24 and at the other end to the clamping base 11. The cylinder body 21 is slidably arranged in the guide cylinder 4. The pneumatic shaft 24 is fixed to the clamping base 11 through the guide cylinder 4, and the cylinder body 21 is slidably arranged in the guide cylinder 4, which provides guidance for the lifting of the cylinder body 21 through the guide cylinder 4, so as to ensure that the clamping pressure plate 12 does not deflect when lifting, and at the same time disperses the bending moment load of the pneumatic pressure thrust on the clamping base 11, reduces the deformation of the clamping base 11, and protects the geometric accuracy of the wafer positioning cavity 1111.

[0074] Exemplarily, the top of the guide cylinder 4 extends axially to form a connecting end 42, a through hole 421 is formed in the center of the end face of the connecting end 42, and a sixth sealing ring 66 is embedded in the inner wall of the through hole 421. The pneumatic shaft 24 is designed as a stepped shaft, the small-diameter end of the stepped shaft is inserted into the inner cavity of the guide cylinder 4 through the through hole 421, and the sixth sealing ring 66 forms a radial static seal. The stepped shaft shoulder of the pneumatic shaft 24 is pressed against a stepped ring 245, which is tightly attached to the end face of the connecting end 42 and is fixed by axially distributed fastening bolts to realize zero-gap rigid connection. The outer wall of the guide cylinder 4 is provided with a flange plate 41, which is fixed and locked by fastening bolts with the connecting frame 112.

[0075] In an embodiment, the inner wall of the guide cylinder 4 is provided with a bushing 5, and the cylinder body 21 is in sliding fit with the bushing 5. The precise sliding fit of the bushing 5 and the cylinder body 21 eliminates the radial play, further reduces the deflection angle of the cylinder body 21 during lifting, and at the same time reduces friction and wear rate, prolongs the maintenance cycle.

[0076] In an embodiment, the driving mechanism 2 further comprises a rotary motor 28 connected to the pneumatic shaft 24, which is configured to drive the clamping mechanism 1 to rotate through the pneumatic shaft 24. The rotary motor 28 drives the pneumatic shaft 24 to rotate, which drives the guide cylinder 4 and the piston 22 to rotate, and the guide cylinder 4 drives the clamping mechanism 1 and the cylinder body 21 to rotate together. During rotation, the cylinder body 21 rotates synchronously with the piston 22, eliminating the relative motion friction and reducing the rotation torque. At the same time, the first sealing ring 61 between the piston 22 and the cylinder body 21, the second sealing ring 62 between the cylinder body 21 and the clamping pressure plate 12, the third sealing ring 63 between the pneumatic shaft 24 and the connecting ring 27, the fourth sealing ring 64 between the connecting ring 27 and the stepped hole, the fifth sealing ring 65 between the pneumatic shaft 24 and the piston 22, and the sixth sealing ring 66 between the pneumatic shaft 24 and the guide cylinder 4 all only bear axial shear force, which reduces the wear rate of each sealing ring, ensures the sealing property and avoids the influence of wear particles on the wafer coating.

[0077] Exemplarily, the rotary motor 28 is a hollow rotary motor, the pneumatic shaft 24 is connected with the piston 22 through the central cavity of the hollow rotary motor, and the mover of the hollow rotary motor is connected with the pneumatic shaft 24 through the shaft coupling 3. The pneumatic shaft 24 penetrates the central cavity of the hollow rotary motor, the large-diameter end of the pneumatic shaft 24 is located in the central cavity, and the mover of the hollow rotary motor is rigidly connected with the large-diameter end of the pneumatic shaft 24 through the shaft coupling 3. The flange of the shaft coupling 3 is attached to the upper end surface of the central cavity, the connecting end 42 of the guide cylinder 4 is inserted into the lower end of the central cavity and abuts against the stepped ring 245 of the pneumatic shaft 24, and the upper end surface of the guide cylinder 4 abuts against the lower end surface of the central cavity. The three coaxial structures ensure the rotation accuracy and reduce the deviation of the wafer rotation track.

[0078] In an embodiment, the driving mechanism 2 further comprises a rotary air joint 26 connected to the end of the pneumatic shaft 24 away from the piston 22, and the pneumatic solenoid valve 25 is selectively communicated with the first air channel and the second air channel through the rotary air joint 26. The rotary air joint 26 allows the pneumatic shaft 24 to keep the air path communicated under continuous rotation, which breaks through the limitation of the number of traditional air pipe winding turns.

[0079] In an embodiment, the electroplating clamp further comprises a control unit electrically connected with the pneumatic solenoid valve 25 and the rotary motor 28. The control unit is configured to: in response to a wafer clamping and rotating instruction, control the pneumatic solenoid valve 25 to supply the gas source to the first air channel to drive the clamping pressure plate 12 to press down the wafer fixed on the bottom of the clamping base 11; and control the rotary motor 28 to start and drive the clamping mechanism 1 to rotate at a constant speed.

[0080] Further, the control unit is further configured to: in response to a wafer stopping rotating and releasing instruction, control the rotary motor 28 to stop driving; and control the pneumatic solenoid valve 25 to supply the gas source to the second air channel to drive the clamping pressure plate 12 to move upward to release the wafer located on the bottom of the clamping base 11.

[0081] By electrically connecting the pneumatic solenoid valve 25 and the rotary motor 28 with the control unit, after the wafer is transferred into the wafer positioning cavity 1111 in the clamping base 11 by the robot and the wafer in the wafer positioning cavity 1111 is detected, the control unit receives a wafer clamping and rotating instruction and controls the pneumatic solenoid valve 25 to be powered on in response to the wafer clamping and rotating instruction, the clamping pressure plate 12 presses down to fix the wafer in the wafer positioning cavity 1111, and the rotary motor 28 is controlled to start and drive the clamping mechanism 1 to rotate at a constant speed. When the wafer electroplating is completed, the control unit receives a wafer stopping rotating and releasing instruction, the pneumatic solenoid valve 25 is controlled to be powered off, the clamping pressure plate 12 moves upward to release the wafer, and the robot can take away the wafer after electroplating, which realizes automatic control and improves production efficiency.

[0082] In an embodiment, the electroplating clamp further comprises a tilting motor for driving the electroplating clamp to tilt, so that the wafer fixed by the electroplating clamp is tilted synchronously, and the tilting angle is less than 30 degrees. During electroplating, the tilting motor drives the electroplating clamp to tilt, so that the wafer clamped by the clamping mechanism 1 is in a tilted state, the electroplating liquid spirally flows along the wafer surface, the diffusion boundary layer thickness is reduced by 35%, the wafer edge-to-center plating layer thickness difference is reduced, and the wafer plating layer uniformity is further ensured.

[0083] The embodiment also provides an electroplating device, which comprises an electroplating cavity and an electroplating clamp arranged above the electroplating cavity. The electroplating clamp can clamp a wafer and carry the wafer to the electroplating cavity to perform an electroplating process. The electroplating clamp adopts the electroplating clamp described above. The electroplating clamp has a compact structure, the path through which the air pressure driving force is transmitted to the clamping pressure plate 12 is the shortest, the transmission efficiency is the highest, and the response is the fastest. The wafer height rotation stability is ensured, the wafer surface electroplating liquid flow field uniformity is ensured, and the wafer electroplating quality is improved.

[0084] The above is only a preferred embodiment of the present application. Those skilled in the art can make changes in the specific implementation and application range according to the idea of the present application. The content of the specification should not be understood as a limitation of the present application.

Claims

1. An electroplating fixture, characterized by, The utility model relates to a wafer clamping device, including: Clamping mechanism (1), including clamping base (11) and opposite the clamping base (11) can be lifted and arranged clamping pressing plate (12); Driving mechanism (2), including cylinder (21), piston (22) and pneumatic axle (24), the cylinder (21) has the closed hollow chamber, and the bottom of cylinder (21) is fixedly connected with clamping pressing plate (12);Piston (22) is fixedly arranged in the hollow chamber, and the hollow chamber is divided into closed first cavity (211) and second cavity (212), and the first cavity (211) is located below the second cavity (212);Pneumatic axle (24) passes through the second cavity (212) and is connected with piston (22);The pneumatic axle (24) has first airway and second airway in it, the first airway communicates with the first cavity (211), and the second airway communicates with the second cavity (212);The pneumatic axle (24) has concentrically arranged first hole (241) and second hole (242), the first hole (241) is located in the middle of the second hole (242) and penetrates the pneumatic axle (24) near one end of clamping mechanism (1), forms the first airway;The both ends of second hole (242) are all closed, and a plurality of air inlet holes (243) are uniformly distributed in one closed end of second hole (242), a plurality of air outlet holes (244) are uniformly distributed in the other closed end, and a plurality of air inlet holes (243), second hole (242) and a plurality of air outlet holes (244) form the second airway; When the pressure inside the first cavity (211) is greater than the pressure inside the second cavity (212), the cylinder (21) drives the clamping pressing plate (12) to move downward, and the wafer fixedly located at the bottom of the clamping base (11) is pressed; when the pressure inside the first cavity (211) is less than the pressure inside the second cavity (212), the cylinder (21) drives the clamping pressing plate (12) to move upward to release the wafer located at the bottom of the clamping base (11) upward.

2. The electroplating fixture of claim 1, wherein, The cylinder (21) includes a side wall, a top wall, and a bottom wall connected to the side wall, the side wall, the top wall, and the bottom wall form the hollow chamber, and the bottom wall is fixedly connected to the upper part of the clamping pressing plate (12).

3. The electroplating fixture of claim 1, wherein, The cylinder (21) includes a side wall and a top wall connected to the side wall, the side wall is extendedly provided with a sealing plate (23), the sealing plate (23) is sealingly and fixedly connected to the upper surface of the clamping pressing plate (12), so that the side wall, the top wall, the sealing plate (23), and the corresponding part of the upper surface of the clamping pressing plate (12) form the hollow chamber.

4. The electroplating fixture of claim 2 or 3, wherein, The peripheral wall of the piston (22) is provided with a sealing groove (221), a first sealing ring (61) is embedded in the sealing groove (221), the first sealing ring (61) seals the upper part of the first cavity (211) and the lower part of the second cavity (212), so that the first cavity (211) and the second cavity (212) are in a sealed state.

5. The electroplating fixture of claim 1, wherein, The driving mechanism (2) further comprises an air source and a pneumatic electromagnetic valve (25) for controlling the air source to selectively supply air to the first air channel or the second air channel.

6. The electroplating fixture of claim 5, wherein, The pneumatic electromagnetic valve (25) is a two-position five-way electromagnetic valve, which comprises an air inlet, a down pressure control interface, a return control interface, a first exhaust interface and a second exhaust interface, the air inlet is connected with the air source, the down pressure control interface is communicated with the first air channel, and the first exhaust interface is communicated with a first exhaust channel; the return control interface is communicated with the second air channel, and the second exhaust interface is communicated with a second exhaust channel.

7. The electroplating fixture of claim 5, wherein, The electroplating clamp further comprises a guide cylinder (4) sleeved outside the pneumatic shaft (24) and fixed at one end with the pneumatic shaft (24) and at the other end with the clamping base (11). The cylinder body (21) is slidably arranged in the guide cylinder (4).

8. The electroplating fixture of claim 7, wherein, The inner wall of the guide cylinder (4) is provided with a bushing (5), and the cylinder body (21) is in sliding fit with the bushing (5).

9. The electroplating fixture of claim 5, wherein, The driving mechanism (2) further comprises a rotary motor (28) drivingly connected with the pneumatic shaft (24), and the rotary motor (28) is configured to drive the clamping mechanism (1) to rotate through the pneumatic shaft (24).

10. The electroplating fixture of claim 9, wherein, The rotary motor (28) is a hollow rotary motor, the pneumatic shaft (24) passes through the center cavity of the hollow rotary motor and is connected with the piston (22), and the mover of the hollow rotary motor is connected with the pneumatic shaft (24) through a shaft coupling (3).

11. The electroplating fixture of claim 5, wherein, The driving mechanism (2) further comprises a rotary air joint (26) connected with one end of the pneumatic shaft (24) away from the piston (22), and the pneumatic electromagnetic valve (25) is selectively communicated with the first air channel or the second air channel through the rotary air joint (26).

12. The electroplating fixture of claim 9, wherein, The electroplating clamp further comprises a control unit electrically connected with the pneumatic electromagnetic valve (25) and the rotary motor (28) respectively. The control unit is configured to, in response to a wafer clamping and rotating instruction, control the pneumatic electromagnetic valve (25) to make the air source supply air to the first air channel, drive the clamping pressure plate (12) to press down and fix the wafer at the bottom of the clamping base (11), and control the rotary motor (28) to start and drive the clamping mechanism (1) to rotate at a constant speed.

13. The electroplating fixture of claim 12, wherein, The control unit is further configured to, in response to a wafer stopping rotating and releasing instruction, control the rotary motor (28) to stop driving, and control the pneumatic electromagnetic valve (25) to make the air source supply air to the second air channel, drive the clamping pressure plate (12) to loosen the wafer at the bottom of the clamping base (11) upward.

14. The electroplating fixture of claim 1, wherein, The electroplating clamp further comprises an inclination motor for driving the electroplating clamp to incline, so that the wafer fixed by the electroplating clamp is synchronously inclined, and the inclination angle is less than 30 degrees.

15. An electroplating apparatus comprising an electroplating chamber and an electroplating clamp disposed above the electroplating chamber, the electroplating clamp capable of clamping a wafer and carrying the wafer to the electroplating chamber to perform an electroplating process, characterized in that, The electroplating clamp is the electroplating clamp according to any one of claims 1-14.

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