Electrochemical mechanical polishing and planarization device

Abstract

The invention discloses an electrochemical mechanical polishing and planarization device which at least comprises a polishing head, and the polishing head comprises a polishing head body; the hard conductive disc is used for adsorbing a wafer substrate; at least part of the conductive driving unit can be connected with a power supply, and at least part of the conductive driving unit makes contact with the hard conductive disc and is in transmission fit with the hard conductive disc so as to drive the hard conductive disc to rotate circumferentially; the movable gap is formed between the polishing head body and the conductive driving unit, and / or formed between the conductive driving unit and the hard conductive disc, and / or formed between the hard conductive disc and the polishing head body; a retaining ring, an annular member that can be in contact with the polishing pad, the hard conductive disk moving within a region defined by the retaining ring. According to the invention, the hard conductive disc is utilized to realize circuit conduction between the polishing head and the wafer substrate for electrochemical mechanical polishing, so that the long-term stability of electrochemical reaction can be guaranteed; and the hard conductive disc is utilized to adsorb the wafer substrate under negative pressure, so that the problem that the flexible film is broken due to pulling is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor integrated circuit chip manufacturing, and particularly relates to an electrochemical mechanical polishing and planarization device. Background Art

[0002] The manufacturing process of a wafer substrate and semiconductor devices includes processes such as polishing and surface planarization. Generally, mechanical polishing, chemical mechanical polishing or planarization and other technologies are adopted. By applying pressure to the back of the wafer through a wafer carrier head (polishing head), parameters such as pressure, polishing head rotation speed, polishing pad rotation speed, and polishing liquid flow rate are controlled to polish or planarize the front surface of the wafer substrate or the thin film surface on the polishing pad. Compared with mechanical polishing, chemical mechanical polishing and planarization can generate chemical reactions on the wafer surface by adjusting the polishing liquid formula, achieving higher polishing or planarization processing efficiency, and at the same time, better polishing or planarization processing effects, including higher flatness, lower defect density, etc. On the basis of chemical mechanical polishing and planarization, for conductive substrates or film layer conductive materials, electrochemical mechanical polishing and planarization can further utilize the conductive characteristics of the wafer substrate or the thin film on the wafer surface to form a current path, carry out electrochemical reactions on the wafer substrate or the thin film surface, and improve the surface chemical reaction speed through precise control of the circuit system, thereby improving the mechanical polishing and planarization efficiency.

[0003] Generally, in chemical mechanical polishing or planarization technology, when the polishing head drives the wafer to polish on the polishing pad, the polishing head will rotate itself to drive the flexible film to rotate to drive the wafer to polish. If a conventional flexible film is used in electrochemistry to drive wafer polishing, then when the polishing head rotates, it relies on the flexible film to drive the conductive disk to rotate. The flexible film itself needs to bear the pulling force brought by the rotation of the polishing head itself and the sweeping of the polishing head by the polishing arm on the polishing pad. Under harsh polishing conditions, the pulling force on the flexible film during the polishing process may be too large, causing it to rupture and leading to safety accidents. In addition, in the existing CMP polishing process, from the start of polishing to the end of the polishing process, when the polishing head stops working and leaves the polishing pad, the return of the flexible film will cause the wafer to scratch the polishing pad, affecting the polishing process. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides an electrochemical mechanical polishing and planarization device, which uses a hard conductive disk to adsorb the wafer substrate under negative pressure and cooperate with a conductive driving unit to achieve electrical conduction. The conductive driving unit plays the functions of electrical conduction and mechanical driving, while ensuring effective electrochemical mechanical polishing of the wafer substrate, extending the service life of the polishing head.

[0005] The technical solution adopted by the present invention to solve its technical problems is: an electrochemical mechanical polishing and planarization device, at least including a polishing head, and the polishing head includes:

[0006] Polishing head body;

[0007] Hard conductive disk, at least part of its lower surface is in the same plane, for adsorbing the wafer substrate;

[0008] Conductive driving unit, at least part of which can be connected to a power source, at least part of which is in contact with and in transmission cooperation with the hard conductive disk to drive the hard conductive disk to rotate circumferentially;

[0009] Moving gap, formed between the polishing head body and the conductive driving unit, and / or formed between the conductive driving unit and the hard conductive disk, and / or formed between the hard conductive disk and the polishing head body;

[0010] Retention ring, located below the polishing head body, an annular part that can contact the polishing pad, and the hard conductive disk moves within the area defined by the retention ring.

[0011] Furthermore, air holes are provided in the part of the lower surface of the hard conductive disk that is in the same plane, and the air holes are connected to a third air cavity inside the hard conductive disk. When the third air cavity is in a negative pressure state, the hard conductive disk can adsorb the wafer substrate.

[0012] Furthermore, there is also a second air cavity with controllable pressure, which is used to drive the hard conductive disk to move up and down.

[0013] Furthermore, the hard conductive disk and the conductive driving unit are integrally connected, or the hard conductive disk and the conductive driving unit are separately arranged.

[0014] Furthermore, the moving gap at least includes a radial moving gap and an axial moving gap.

[0015] Furthermore, the conductive driving unit includes a guide rod and a second driving part. The second driving part is connected to the hard conductive disk. The polishing head body forms a first driving part that is in transmission cooperation with the second driving part. The moving gap is formed between the first driving part and the second driving part, and the second driving part remains in contact with the first driving part to achieve electrical conduction.

[0016] Furthermore, the conductive driving unit includes an electrically connected guide block and a wire. The guide block is connected to the polishing head body, so that the polishing head body drives the hard conductive disk to rotate circumferentially through the guide block and conducts current to the hard conductive disk during driving; the hard conductive disk forms a groove for the guide block to extend into, and the moving gap is formed between the guide block and the groove.

[0017] Furthermore, the number of the guide blocks is multiple, which are arranged at intervals along the circumference of the polishing head body, and the guide blocks remain in contact with the groove to achieve electrical conduction.

[0018] Further, the number of the wires is one or corresponding to the number of the conductive blocks. When the number of the wires is one, all the conductive blocks are connected into a whole through the ring body.

[0019] Further, the conductive driving unit includes a guide rod and a second driving part. The guide rod is connected with an external power source, and the hard conductive disk forms a third driving part which is in transmission cooperation with the second driving part. The moving gap is formed between the second driving part and the third driving part.

[0020] Further, the conductive driving unit includes an elastic unit which is respectively connected with the polishing head body and the hard conductive disk, so that the polishing head body, the elastic unit and the hard conductive disk enclose to form the second air cavity.

[0021] Further, the hard conductive disk has a flange which extends into the polishing head body and is in sealing cooperation with the polishing head body through a seal to form the second air cavity and the moving gap, and the flange is electrically connected with the polishing head body.

[0022] Further, the rotation direction of the hard conductive disk is the same as or opposite to the rotation direction of the polishing head body.

[0023] Further, the lower surface of the hard conductive disk is located in the same plane; or, the part of the lower surface of the hard conductive disk located in the same plane forms a thickened area or a thinned area to form a height difference from nanometer level to micrometer level.

[0024] Further, a flexible conductive cloth is attached to the lower surface of the hard conductive disk. The flexible conductive cloth contains holes which are matched with the positions of at least part of the air holes of the hard conductive disk.

[0025] The beneficial effects of the present invention are as follows: 1) By using a hard conductive disk, the electrical connection between the polishing head and the wafer substrate is achieved for electrochemical mechanical polishing, which can ensure the long-term stability of the electrochemical reaction and the higher process stability of electrochemical mechanical polishing; 2) By using the hard conductive disk to adsorb the wafer substrate under negative pressure, the problem that the flexible film is pulled and broken or the elastic modulus changes under harsh polishing conditions when the flexible film drives the wafer substrate for polishing is solved, and the service life of the flexible part in the polishing head is extended; 3) By using the hard conductive disk to adsorb the wafer substrate under negative pressure, during the process of the polishing head leaving the polishing pad, the wafer substrate will not be scratched by the polishing pad due to the return of the flexible film, ensuring that the wafer substrate quickly and effectively detaches from the polishing pad and guaranteeing the orderly progress of the polishing process; 4) When the flexible film drives the wafer substrate for polishing as a driving component, when encountering areas such as grooves on the polishing pad, the force balance state fluctuates, which will affect the polishing speed and the polishing efficiency will be adversely affected. However, the hard drive in the hard conductive disk has higher stability and can effectively avoid the above problems, and the process stability is better; 5) The conductive drive unit not only plays the function of conducting electricity, but also can mechanically drive the hard conductive disk to carry out the polishing process with the wafer substrate. The existence of the moving gap provides a moving space for the up, down, left and right floating of the hard conductive disk, making the polishing more flexible. 6) By using the cooperation mode of the baffle and the polishing head body, the self-control function of the rotation direction of the hard conductive disk can be realized, and its direction can be the same as the rotation direction of the retaining ring and the hard conductive disk, or opposite to the rotation direction of the retaining ring and the hard conductive disk, providing more possibilities for the polishing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 FIG. is a schematic three-dimensional structure diagram of the electrochemical mechanical polishing and planarization device provided in Embodiment 1 of the present invention. Figure 1 。

[0027] Figure 2 FIG. is a schematic three-dimensional structure diagram of the electrochemical mechanical polishing and planarization device provided in Embodiment 1 of the present invention. Figure 2 。

[0028] Figure 3 FIG. is a schematic three-dimensional structure diagram of the hard conductive disk and the elastic unit provided in Embodiment 1 of the present invention.

[0029] Figure 4 FIG. is a schematic sectional structure diagram of the hard conductive disk provided in Embodiment 1 of the present invention.

[0030] Figure 5 FIG. is a partial sectional view of the hard conductive disk provided in Embodiment 1 of the present invention.

[0031] Figure 6 FIG. is a sectional view of the electrochemical mechanical polishing and planarization device provided in Embodiment 1 of the present invention.

[0032] Figure 7 This is a schematic diagram of the three-dimensional structure of the hard conductive disk provided in the first embodiment of the present invention.

[0033] Figure 8 This is a schematic diagram of the three-dimensional structure of the polishing head body provided in the first embodiment of the present invention.

[0034] Figure 9 This is a schematic diagram of the three-dimensional structure of the electrochemical mechanical polishing and planarization device provided in the second embodiment of the present invention.

[0035] Figure 10 This is a front view of the electrochemical mechanical polishing and planarization device provided in the second embodiment of the present invention.

[0036] Figure 11 This is a schematic diagram of the three-dimensional structure of the hard conductive disk and the elastic unit provided in the second embodiment of the present invention.

[0037] Figure 12 A cross-sectional view of an electrochemical mechanical polishing and planarization device provided in Embodiment 2 of the present invention Figure 1 .

[0038] Figure 13 A cross-sectional view of an electrochemical mechanical polishing and planarization device provided in Embodiment 2 of the present invention Figure 2 .

[0039] Figure 14 This is a schematic diagram of the three-dimensional structure of the hard conductive disk and the elastic unit provided in the third embodiment of the present invention.

[0040] Figure 15 This is a cross-sectional view of the electrochemical mechanical polishing and planarization device provided in Example 3 of the present invention.

[0041] Figure 16 This is a schematic diagram of the hard conductive disk, conductive drive unit, and external power coordination structure provided in the third embodiment of the present invention.

[0042] Figure 17 for Figure 16 A magnified view of the structure in Figure 2.

[0043] Figure 18 This is a schematic diagram of the three-dimensional structure of the hard conductive disk provided in the third embodiment of the present invention.

[0044] Figure 19 A cross-sectional view of an electrochemical mechanical polishing and planarization device provided in Embodiment 4 of the present invention.

[0045] Figure 20 This is a schematic diagram of the coordination structure of the hard conductive disk and the conductive drive unit provided in the fourth embodiment of the present invention.

[0046] Figure 21Schematic three-dimensional structure diagram of the polishing head body provided in Embodiment 4 of the present invention.

[0047] Figure 22 Cross-sectional view of the electrochemical mechanical polishing and planarization device provided in Embodiment 5 of the present invention.

[0048] Figure 23 Schematic three-dimensional structure diagram of the hard conductive disk provided in Embodiment 5 of the present invention.

[0049] Figure 24 Cross-sectional view of the electrochemical mechanical polishing and planarization device provided in Embodiment 6 of the present invention.

[0050] Figure 25 Schematic diagram of the cooperation structure of the hard conductive disk, the conductive driving unit and the external power in Embodiment 6 of the present invention.

[0051] Figure 26 Schematic three-dimensional structure diagram of the hard conductive disk provided in Embodiment 6 of the present invention.

[0052] Among them, 1 - polishing head body, 11 - first air cavity, 12 - annular groove, 2 - hard conductive disk, 21 - air hole, 22 - third air cavity, 23 - groove, 24 - edge stop, 25 - air passage, 3 - conductive driving unit, 31 - guide rod, 311 - external gear ring, 312 - external power, 32 - second driving part, 33 - first driving part, 34 - guide block, 35 - wire, 36 - ring body, 37 - third driving part, 4 - moving gap, 41 - radial moving gap, 42 - axial moving gap, 5 - retaining ring, 6 - second air cavity, 7 - elastic unit, 8 - seal. Detailed implementation manners

[0053] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0054] Embodiment 1

[0055] As Figure 1 , Figure 2 shown, an electrochemical mechanical polishing and planarization device at least includes a polishing head, and the polishing head includes a polishing head body 1, a hard conductive disk 2, a conductive driving unit 3, a moving gap 4, and a retaining ring 5 located below the polishing head body 1.

[0056] The hard conductive disk 2 means that the conductive disk is made of a hard material, such as metal, conductive material or other conductive materials with rigidity. The metal can specifically be aluminum, titanium, stainless steel, and other conductive materials can be conductive ceramics, graphite, etc. The above materials are all conductive materials. Thus, the hard conductive disk 2 can form a conduction loop required for electrochemical mechanical polishing with the wafer substrate, polishing table, and power supply. After being energized and conducted to the hard conductive disk 2, it is then conducted to the wafer substrate for surface modification, and then mechanical polishing is carried out. In this embodiment, the lower surfaces of the hard conductive disks 2 are all located in the same plane. Of course, in other embodiments, the planar roughness of the horizontal part of the hard conductive disk 2 can also be thickened or thinned in specific areas according to the thickness and topography of the wafer substrate, that is, a thickened area or a thinned area is formed to form a height difference from nanoscale to micron scale between different areas. In other embodiments, the side surfaces of the hard conductive disks 2 can be insulated and chamfered. The insulation treatment includes, but is not limited to, hard anodization, surface plating and other methods.

[0057] In this embodiment, the hard conductive disk 2 has a disk-shaped structure, such as Figure 5 shown, the upper surface of the hard conductive disk 2 is airtight, at least part of the lower surface of the hard conductive disk 2 is located in the same plane, and a plurality of air holes 21 are provided in the part of the lower surface located in the same plane. A third air cavity 22 communicating with the air holes 21 is provided inside the hard conductive disk 2. The third air cavity 22 must be connected in a closed manner to prevent the polishing liquid from leaking and polluting the polishing head. In other cases where it does not affect the internal environment of the polishing head in terms of other functions, it can be realized by any connection method, such as tracheal connection, screw plus sealing ring connection of the machine body itself, flexible membrane cavity design and other sealing designs. It can be realized by existing technologies and will not be elaborated here. The diameter of the air holes 21 is 0.1 - 3 mm, and the total area of all the air holes 21 accounts for 0.1 - 5% of the lower surface area of the hard conductive disk 2. When a negative pressure is formed in the third air cavity 22, the lower surface of the hard conductive disk 2, specifically the part of the lower surface located in the same plane, can directly contact and adsorb the wafer substrate.

[0058] In this embodiment, all the air holes 21 are connected, such as Figure 4 shown, a radially staggered and connected air path channel 25 is formed inside the hard conductive disk 2. The air path channel 25 is connected to the third air cavity 22, and the air holes 21 are correspondingly arranged in the area where the air path channel 25 is located. Therefore, the negative pressure formed by all the air holes 21 is relatively balanced.

[0059] One of the judgment logics for whether the wafer substrate is loaded onto the polishing head body 1 is to perform a pressure holding test after evacuating the third air cavity 22 to detect the vacuum condition of the third air cavity 22. If the negative pressure is maintained, the wafer substrate is on the polishing head body 1; otherwise, the wafer substrate is not on the polishing head body 1.

[0060] The holding ring 5 is an annular component that can contact the polishing pad, and the hard conductive disk 2 moves within the area defined by the holding ring 5.

[0061] A first air cavity 11 is formed in the polishing head body 1, which is used to control the up and down movement and the lifting stroke of the polishing head body 1 part, and further drive the hard conductive disk 2 and the wafer substrate to move up and down. The polishing head further includes a second air cavity 6 with controllable pressure, and the second air cavity 6 is used to drive the hard conductive disk 2 to move up and down.

[0062] In this embodiment, the conductive driving unit 3 further includes an elastic unit 7, which is connected to the polishing head body 1 and the hard conductive disk 2 respectively. Specifically, as Figure 3 shown, the elastic unit 7 is made of an elastic material and is generally in an annular structure. One side of it is connected to the outer ring of the hard conductive disk 2, and the other side is fixedly connected between the polishing head body 1 and the holding ring 5. The elastic unit 7 and the polishing head body 1 and the hard conductive disk 2 enclose to form a second air cavity 4. The pressure in the second air cavity 4 is controllable. Thus, by adjusting the pressure in the second air cavity 4, the elastic unit 7 can be driven to perform a flexible movement, assisting the hard conductive disk 2 and the wafer substrate to float, and realizing the electrochemical mechanical polishing of the wafer substrate. Here, the floating of the hard conductive disk 2 and the wafer substrate means that on the premise of the mechanical drive of the polishing head body 1 and the hard conductive disk 2, the activity of the hard conductive disk 2 and the wafer substrate is improved by using the elastic unit 7, and the activity includes up and down floating and radial floating. The control method of the pressure in the second air cavity 4 is a prior art and will not be elaborated.

[0063] Of course, on the basis that the circuit is directly connected from the power electrode to the hard conductive disk 1 during the electrochemical mechanical polishing and planarization of the wafer substrate, the circuit can also be connected from the elastic unit 7 to the hard conductive disk 2 to realize the function of the hard conductive disk 2, and the specific details are not limited.

[0064] Part of the conductive driving unit 3 extends out of the polishing head body 1 and can be connected to a power supply. Part of the conductive driving unit 3 contacts and is in transmission cooperation with the hard conductive disk 2, so as to drive the hard conductive disk 2 to rotate circumferentially. The power supply here is not specifically limited as long as it can supply power.

[0065] An active gap 4 is formed between the polishing head body 1 and the conductive drive unit 3; alternatively, the active gap 4 is formed between the conductive drive unit 3 and the hard conductive disk 2; alternatively, the active gap 4 is formed between the hard conductive disk 2 and the polishing head body 1; alternatively, an active gap 4 is formed between the polishing head body 1 and the conductive drive unit 3, and at the same time, an active gap 4 is also formed between the conductive drive unit 3 and the hard conductive disk 2; alternatively, an active gap 4 is formed between the polishing head body 1 and the conductive drive unit 3, and at the same time, an active gap 4 is also formed between the hard conductive disk 2 and the polishing head body 1; alternatively, an active gap 4 is formed between the conductive drive unit 3 and the hard conductive disk 2, and at the same time, an active gap 4 is also formed between the hard conductive disk 2 and the polishing head body 1.

[0066] The conductive drive unit 3 includes a guide rod 31 and a second drive part 32. The second drive part 32 is connected to the hard conductive disk 2, and at this time, the hard conductive disk 2 is integrally connected to the second drive part 32 of the conductive drive unit 3; the guide rod 31 is connected to the hard conductive disk 2, and at this time, the hard conductive disk 2 and the guide rod 31 are integrally connected. Of course, it can also be that the guide rod 31 is connected to the second drive part 32, and at this time, the hard conductive disk 2 is integrally connected to the guide rod 31 and the second drive part 32.

[0067] A first drive part 33 that is in transmission cooperation with the second drive part 32 is formed on the polishing head body 1, and the active gap 4 described above is formed between the first drive part 33 and the second drive part 32.

[0068] Specifically, as Figures 6 - 8 shown, the guide rod 31 is of a hollow cylindrical structure. Its bottom end is integrally connected to the upper surface (the side without the air holes 21) of the hard conductive disk 2, and its top end extends out from the polishing head body 1; the second drive part 32 includes a plurality of sector-shaped protrusions arranged at intervals around the guide rod 31, and it is fixedly connected to the outer wall of the guide rod 31. Of course, the specific shape of the protrusion is not limited, and it can also be square.

[0069] The first driving part 33 is a groove structure for the second driving part 32 to extend into. When the polishing head body 1 rotates circumferentially, through the cooperation of the first driving part 33 and the second driving part 32, the hard conductive disk 2 can be driven to rotate circumferentially. And the cross-sectional area of the first driving part 33 is larger than that of the second driving part 32. Thus, while the second driving part 32 realizes electrical conduction by fitting to the bottom of the groove of the first driving part 33, the second driving part 32 can also move radially within the first driving part 33 (here, the radial direction refers to the diameter direction of the hard conductive disk 2). Or, the power supply is connected to the first driving part 33 to make it charged. While the second driving part 32 realizes electrical conduction by fitting to the side wall of the groove of the first driving part 33, the second driving part 32 can also move axially within the first driving part 33. In other words, the second driving part 32 at least fits to the side wall or the bottom wall of the first driving part 33 to realize electrical conduction.

[0070] Of course, in other embodiments, it can also be that the first driving part 33 is a convex block and the second driving part 32 is a groove, and no specific limitation is made.

[0071] The radial movement gap 41 and the axial movement gap 42 between the above-mentioned first driving part 33 and the second driving part 32 form the movement gap 4, that is, the movement gap 4 is formed between the polishing head body 1 and the conductive driving unit 3. Thus, when the pressure in the second air chamber 4 is adjusted, the elastic unit 7 can be driven to perform a flexible movement to assist the hard conductive disk 2 and the wafer substrate to float, and this floating is completed within the above-mentioned movement gap 4; the hard conductive disk 2 can form a conduction loop required for electrochemical mechanical polishing with the wafer substrate, the polishing table, and the power supply, and the conductive rod 31 is used to conduct electricity to the hard conductive disk 2 and then conduct it to the wafer substrate for surface modification, and then the electrochemical mechanical polishing of the wafer substrate is realized.

[0072] Embodiment 2

[0073] As Figures 9 - 11As shown, in this embodiment, the conductive driving unit 3 includes a conductive block 34 and a wire 35 that are electrically connected. The conductive block 34 is connected to the polishing head body 1. The hard conductive disk 2 forms a groove 23 for the conductive block 34 to extend into. That is, at this time, the hard conductive disk 2 and the conductive driving unit 3 are separately arranged. When the polishing head body 1 rotates circumferentially, through the cooperation of the conductive block 34 and the groove 23, the hard conductive disk 2 can be driven to rotate circumferentially. And the cross-sectional area of the groove 23 is larger than that of the conductive block 34. Thus, while the conductive block 34 realizes electrical conduction in contact with the bottom of the groove body of the groove 23, the conductive block 34 can also move radially within the groove 23 (the radial direction here refers to the diameter direction of the hard conductive disk 2), or while the conductive block 34 realizes electrical conduction in contact with the side wall of the groove 23, the conductive block 34 can also move axially within the groove 23. In other words, the polishing head body 1 drives the hard conductive disk 2 to rotate circumferentially through the conductive block 34 and conducts current to the hard conductive disk 2 during driving. The conductive block 34 is at least in contact with the side wall or the bottom wall of the groove 23 to achieve electrical conduction.

[0074] In this embodiment, the number of conductive blocks 34 is multiple, and they are arranged at intervals along the circumferential direction of the polishing head body 1. Correspondingly, the number of grooves 23 is the same as that of the conductive blocks 34. The number of wires 35 is one or corresponding to the number of conductive blocks 34.

[0075] When the number of wires 35 is one, all the conductive blocks 34 are connected into one body through a ring body 36, as Figure 12 、 Figure 13 shown.

[0076] The radial movement gap 41 and the axial movement gap 42 between the above-mentioned conductive block 34 and the groove 23 form the movement gap 4. That is, the movement gap 4 is formed between the conductive driving unit 3 and the hard conductive disk 2. Since the conductive block 34 is connected to the polishing head body 1, it can also be said that the movement gap 4 is formed between the hard conductive disk 2 and the polishing head body 1. Thus, when adjusting the pressure in the second air chamber 4, the elastic unit 7 can be driven to perform a flexible movement to assist the hard conductive disk 2 and the wafer substrate to float, and this floating is completed within the above-mentioned movement gap 4; the hard conductive disk 2 can form a conduction loop required for electrochemical mechanical polishing with the wafer substrate, the polishing table, and the power supply. The wire 35 is used to conduct electricity to the conductive block 34 and then to the wafer substrate for surface modification, and then the electrochemical mechanical polishing of the wafer substrate is realized.

[0077] Others are the same as those in Embodiment 1 and will not be elaborated here.

[0078] Embodiment 3

[0079] As Figures 14 - 18As shown, the conductive driving unit 3 includes a guide rod 31 and a second driving part 32. The top end of the guide rod 31 is connected to an external power source 312, which can be a motor. The hard conductive disk 2 forms a third driving part 37 that is in transmission cooperation with the second driving part 32. That is, at this time, the hard conductive disk 2 and the conductive driving unit 3 are separately arranged, and an activity gap 4 is formed between the second driving part 32 and the third driving part 37.

[0080] Specifically, the guide rod 31 has a cylindrical or hollow cylindrical structure. Its bottom end is integrally connected to the second driving part 32. Its top end extends out of the polishing head body 1 and has an external gear ring 311. The motor drives the guide rod 31 to rotate circumferentially through transmission with the external gear ring 311, thereby driving the second driving part 32 to rotate. The second driving part 32 includes a plurality of sector-shaped convex blocks arranged at intervals around the guide rod 31, and they are fixedly connected to the outer wall of the guide rod 31.

[0081] The third driving part 37 is a groove structure formed on the upper surface (the side without the air holes 21) of the hard conductive disk 2, and it is for the second driving part 32 to extend into. When the second driving part 32 rotates circumferentially, through the cooperation of the second driving part 32 and the third driving part 37, the hard conductive disk 2 can be driven to rotate circumferentially.

[0082] Connect the power source to the second driving part 32 to make it charged, and the cross-sectional area of the third driving part 37 is larger than that of the second driving part 32. Thus, while the second driving part 32 realizes electrical conduction when fitting to the bottom of the groove of the third driving part 37, the second driving part 32 can also perform radial movement (here, the radial direction refers to the diameter direction of the hard conductive disk 2) within the third driving part 37. Or, while the second driving part 32 realizes electrical conduction when fitting to the side wall of the groove of the third driving part 37, the second driving part 32 can also perform axial movement within the third driving part 37. In other words, the second driving part 32 at least fits to the side wall or the bottom wall of the third driving part 37 to realize electrical conduction.

[0083] Of course, in other embodiments, it can also be that the third driving part 37 is a convex block and the second driving part 32 is a groove, and there is no specific limitation.

[0084] The radial movement gap 41 and the axial movement gap 42 between the above-mentioned third driving part 37 and the second driving part 32 form the activity gap 4. Thus, when adjusting the pressure in the second air cavity 4, the elastic unit 7 can be driven to perform a flexible movement to assist the hard conductive disk 2 and the wafer substrate to float, and this floating is completed within the above-mentioned activity gap 4; the hard conductive disk 2 can form a conduction loop required for electrochemical mechanical polishing with the wafer substrate, the polishing table, and the power source. After the current is conducted to the hard conductive disk 2 through the guide rod 31 and then conducted to the wafer substrate for surface modification, the electrochemical mechanical polishing of the wafer substrate is realized.

[0085] The rest is the same as in the first embodiment and will not be elaborated further.

[0086] Fourth Embodiment

[0087] As Figures 19 - 21 shown, the difference from the first embodiment is that in this embodiment, the elastic unit 7 is not provided. On the basis of the disc-shaped structure, the hard conductive disc 2 is further provided with a retaining edge 24. The retaining edge 24 extends vertically from the outer circle towards the polishing head body 1, and the retaining edge 24 extends into the polishing head body 1 and is hermetically fitted with it through a seal 8, thereby forming the above-mentioned second air cavity 6 and the moving gap 4. At the same time, the retaining edge 24 can be electrically connected to the polishing head body 1, that is, in the electrochemical mechanical polishing and planarization of the wafer substrate, the circuit is connected from the retaining edge 24 to the hard conductive disc 2.

[0088] Specifically, an annular groove 12 with a unilateral radial width greater than the thickness of the retaining edge 24 is formed on the polishing head body 1, thereby forming a radial moving gap 41 in the moving gap 4. The side wall of the annular groove 12 is provided with a seal 8, and the outer wall of the retaining edge 24 abuts against the seal 8 to achieve a sealing fit, and the retaining edge 24 can float left and right in the annular groove 12. The depth of the annular groove 12 is greater than the height that the retaining edge 24 can extend into the annular groove 12, thereby forming an axial moving gap 42 in the moving gap 4, that is, the retaining edge 24 can float up and down in the annular groove 12.

[0089] The same as in the first embodiment, the conductive driving unit 3 includes a guide rod 31 and a second driving part 32. The second driving part 32 is connected to the hard conductive disc 2, and a first driving part 33 that is in transmission cooperation with the second driving part 32 is formed on the polishing head body 1. The above-mentioned moving gap 4 is formed between the first driving part 33 and the second driving part 32. In other words, while a moving gap 4 is formed between the conductive driving unit 3 and the hard conductive disc 2, a moving gap 4 is also formed between the hard conductive disc 2 and the polishing head body 1.

[0090] In this embodiment, since it is not restricted by the elastic unit 7, the retaining edge 24 can rotate at any angle in the annular groove 12. That is to say, the rotation direction of the hard conductive disc 2 and the rotation direction of the polishing head body 1 can be the same or opposite.

[0091] For example, to reduce the loss of the retaining ring 5, the rotation directions of the retaining ring 5 and the hard conductive disc 2 are the same, that is, the rotation directions of the hard conductive disc 2 and the polishing head body 1 are the same. If the rotation direction of the hard conductive disc 2 is opposite to that of the retaining ring 5 and the polishing head body 1, the removal rate of the wafer substrate surface can be increased. Specifically, when the polishing table rotates counterclockwise and the hard conductive disc 2 drives the wafer substrate to rotate clockwise, the polishing removal rate is greatly improved. The rest is the same as in the first embodiment and will not be elaborated further.

[0092] Fifth Embodiment

[0093] AsFigure 22 , Figure 23 As shown, in this embodiment, the elastic unit 7 is not provided. On the basis of the disc-shaped structure, the hard conductive disc 2 is further provided with a retaining edge 24. The specific mating structure is the same as that of the fourth embodiment and will not be elaborated herein.

[0094] Similar to the second embodiment, the conductive driving unit 3 includes a guide block 34 and a wire 35 that are electrically connected. The guide block 34 is connected to the polishing head body 1. The hard conductive disc 2 forms a groove 23 for the guide block 34 to extend into. When the polishing head body 1 rotates circumferentially, through the cooperation of the guide block 34 and the groove 23, the hard conductive disc 2 can be driven to rotate circumferentially. The radial clearance 41 and the axial clearance 42 between the guide block 34 and the groove 23 form the clearance 4.

[0095] Of course, the positions of the guide block 34 and the groove 23 can also be interchanged. Connect the guide block 34 to the hard conductive disc 2, and form a groove 23 for the guide block 34 to extend into on the polishing head body 1, so as to form a clearance 4 between the polishing head body 1 and the conductive driving unit 3. Then, while forming a clearance 4 between the polishing head body 1 and the conductive driving unit 3, a clearance 4 is also formed between the hard conductive disc 2 and the polishing head body 1.

[0096] Others are the same as those in the first embodiment and will not be elaborated herein.

[0097] Embodiment Six

[0098] As Figures 24 - 26 shown, in this embodiment, the elastic unit 7 is not provided. On the basis of the disc-shaped structure, the hard conductive disc 2 is further provided with a retaining edge 24. The specific mating structure is the same as that of the fourth embodiment and will not be elaborated herein.

[0099] Similar to the third embodiment, the conductive driving unit 3 includes a guide rod 31 and a second driving part 32. The top of the guide rod 31 is connected to an external power source 312. The hard conductive disc 2 forms a third driving part 37 that is in transmission cooperation with the second driving part 32. A clearance 4 is formed between the second driving part 32 and the third driving part 37. Thus, while forming a clearance 4 between the conductive driving unit 3 and the hard conductive disc 2, a clearance 4 is also formed between the hard conductive disc 2 and the polishing head body 1.

[0100] Of course, the positions of the second driving part 32 and the third driving part 37 can also be interchanged. The structure of the second driving part 32 is arranged on the hard conductive disc 2, and the structure of the third driving part 37 is arranged on the conductive driving unit 3.

[0101] Others are the same as those in the first embodiment and will not be elaborated herein.

[0102] Embodiment Seven

[0103] On the basis of Embodiment 1 and Embodiment 3, a radial clearance and an axial clearance are further provided between the outer wall of the guide rod 31 and the polishing head body 1, so that a movable clearance 4 is formed between the polishing head body 1 and the conductive driving unit 3. At the same time, a movable clearance 4 is also formed between the conductive driving unit 3 and the hard conductive disk 2.

[0104] Embodiment 8

[0105] In this embodiment, a flexible conductive cloth is attached to the lower surface of the hard conductive disk 2, and its resistivity < 10 -3 mΩ·cm. The flexible conductive cloth contains air holes, and the positions of the air holes match at least part of the air holes 21 of the hard conductive disk 2, so that when the air chamber 3 is pressurized or evacuated, the air path is smoother, which is beneficial to better adsorbing the wafer substrate when the air chamber 3 is evacuated.

[0106] The other structures are the same as those in any one of Embodiments 1 to 7 and will not be described in detail.

[0107] The above specific embodiments are used to explain the present invention, rather than limiting the present invention. Any modifications and changes made within the spirit and scope of the claims of the present invention fall within the protection scope of the present invention.

Claims

1. An electrochemical mechanical polishing and planarization device, characterized in that: At least includes a polishing head, which includes: Polishing head body (1); A hard conductive disk (2), the lower surface of which is at least partially located in the same plane and is used for adsorbing a wafer substrate; A conductive drive unit (3), at least part of which can be connected to a power source, and at least part of which is in contact with and in transmission cooperation with the hard conductive disk (2) to drive the hard conductive disk (2) to rotate circumferentially; A movable gap (4) is formed between the polishing head body (1) and the conductive drive unit (3), and / or between the conductive drive unit (3) and the hard conductive disk (2), and / or between the hard conductive disk (2) and the polishing head body (1); The retaining ring (5) is located below the polishing head body (1) and is an annular component that can contact the polishing pad. The hard conductive disk (2) moves within the area defined by the retaining ring (5).

2. The electrochemical mechanical polishing and planarization device according to claim 1, characterized in that: The lower surface of the hard conductive disk (2) is provided with an air hole (21) located in the same plane, and the air hole (21) is connected to a third air cavity (22) in the hard conductive disk (2). When the third air cavity (22) is in a negative pressure state, the hard conductive disk (2) can adsorb a wafer substrate.

3. The electrochemical mechanical polishing and planarization device according to claim 1, characterized in that: It also includes a second air cavity (6) with controllable pressure, which is used to drive the hard conductive disk (2) to move up and down.

4. The electrochemical mechanical polishing and planarization device according to claim 3, characterized in that: The hard conductive disk (2) and the conductive drive unit (3) are connected as one body, or the hard conductive disk (2) and the conductive drive unit (3) are arranged separately.

5. The electrochemical mechanical polishing and planarization device according to claim 3, characterized in that: The movable gap (4) comprises at least a radial movable gap (41) and an axial movable gap (42).

6. The electrochemical mechanical polishing and planarization device according to claim 3, characterized in that: The conductive drive unit (3) comprises a guide rod (31) and a second drive part (32), wherein the second drive part (32) is connected to the hard conductive disk (2), the polishing head body (1) forms a first drive part (33) which is in transmission cooperation with the second drive part (32), the movable gap (4) is formed between the first drive part (33) and the second drive part (32), and the second drive part (32) maintains contact with the first drive part (33) to achieve electrical conduction.

7. The electrochemical mechanical polishing and planarization device according to claim 3, characterized in that: The conductive drive unit (3) comprises an electrically connected guide block (34) and a conductive wire (35); the guide block (34) is connected to the polishing head body (1), so that the polishing head body (1) drives the hard conductive disk (2) to rotate circumferentially through the guide block (34), and conducts current to the hard conductive disk (2) during driving; the hard conductive disk (2) forms a groove (23) for the guide block (34) to extend into, and the active gap (4) is formed between the guide block (34) and the groove (23).

8. The electrochemical mechanical polishing and planarization device according to claim 7, characterized in that: There are a plurality of guide blocks (34), which are arranged at intervals along the circumference of the polishing head body (1), and the guide blocks (34) are kept in contact with the grooves (23) to achieve electrical conduction.

9. The electrochemical mechanical polishing and planarization device according to claim 7, characterized in that: The number of the conductive wire (35) is one or corresponds to the number of the guide blocks (34). When the number of the conductive wire (35) is one, all the guide blocks (34) are connected as one through the ring body (36).

10. The electrochemical mechanical polishing and planarization device according to claim 3, characterized in that: The conductive drive unit (3) comprises a guide rod (31) and a second drive part (32), the guide rod (31) being connected to an external power source, the hard conductive disk (2) forming a third drive part (37) that is transmission-coordinated with the second drive part (32), and the movable gap (4) is formed between the second drive part (32) and the third drive part (37).

11. The electrochemical mechanical polishing and planarization device according to claim 6, 7 or 10, characterized in that: The conductive drive unit (3) comprises an elastic unit (7) which is respectively connected to the polishing head body (1) and the hard conductive disk (2), so that the polishing head body (1), the elastic unit (7) and the hard conductive disk (2) surround and form the second air cavity (6).

12. The electrochemical mechanical polishing and planarization device according to claim 6, 7 or 10, characterized in that: The hard conductive disk (2) has a rib (24), which extends into the polishing head body (1) and is sealed with the polishing head body (1) through a seal (8) to form the second air cavity (6) and the movable gap (4), and the rib (24) is electrically connected to the polishing head body (1).

13. The electrochemical mechanical polishing and planarization device according to claim 12, characterized in that: The rotation direction of the hard conductive disk (2) is the same as or opposite to the rotation direction of the polishing head body (1).

14. The electrochemical mechanical polishing and planarization device according to claim 1 or 2, characterized in that: The lower surfaces of the hard conductive disks (2) are located in the same plane; or, the lower surfaces of the hard conductive disks (2) are located in the same plane to form a thickened area or a thinned area, so as to form a height difference from nanometer level to micrometer level.

15. The electrochemical mechanical polishing and planarization device according to claim 2, characterized in that: A flexible conductive cloth is attached to the lower surface of the hard conductive disk (2), and the flexible conductive cloth comprises holes, and the holes match the positions of at least part of the pores (21) of the hard conductive disk (2).

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