Electrochemical mechanical polishing and planarization device

Abstract

The present invention discloses an electrochemical mechanical polishing and planarization apparatus comprising at least a polishing head. The polishing head comprises: a polishing head body; a hard conductive disc used to adsorb a wafer substrate; a conductive drive unit, at least a portion of which may be connected to a power source and at least a portion of which is electrically coupled to contact the hard conductive disc to drive the circumferential rotation of the hard conductive disc; a movable gap formed between the polishing head body and the conductive drive unit, and / or formed between the conductive drive unit and the hard conductive disc, and / or formed between the hard conductive disc and the polishing head body; and a retaining ring which is an annular member capable of contacting a polishing pad, wherein the hard conductive disc moves within an area defined by the retaining ring. The present invention can ensure long-term stability of the electrochemical reaction by performing electrochemical mechanical polishing by electrically conducting the polishing head and the wafer substrate using the hard conductive disc; and can solve the problem of a flexible film being damaged by a pulling force by the hard conductive disc adsorbing the wafer substrate under negative pressure.

Description

Technology Field

[0001] The present invention relates to the field of semiconductor integrated circuit chip manufacturing technology, and in particular to an electrochemical mechanical polishing and planarization apparatus. Background Technology

[0002] The manufacturing process for wafer substrates and semiconductor devices includes processes such as polishing and surface planarization. Generally, techniques such as mechanical polishing, chemical mechanical polishing, or planarization are used. By applying pressure to the back surface of the wafer through a wafer carrier head (polishing head) and controlling parameters such as pressure, polishing head rotation speed, polishing disc rotation speed, and polishing slurry flow rate, polishing or planarization treatment is performed on the front surface of the wafer substrate or the thin film surface on a polishing pad. Compared to mechanical polishing, chemical mechanical polishing and planarization can achieve higher polishing or planarization treatment efficiency by inducing a chemical reaction on the wafer surface through the control of the composition of the polishing slurry, and simultaneously achieve superior polishing or planarization treatment effects, including higher flatness and a lower defect rate. In the case of conductive materials for conductive substrates or film layers, electrochemical mechanical polishing and planarization, based on chemical mechanical polishing and planarization processes, further utilizes the conductive properties of the wafer substrate or wafer surface thin film to form current paths and perform electrochemical reactions on the wafer substrate or thin film surface; through precise control of the circuit system, it enhances the surface chemical reaction rate and further improves mechanical polishing and planarization efficiency.

[0003] Generally, in chemical mechanical polishing or planarization technology, when a polishing head polishes a wafer on a polishing pad, the polishing head rotates itself to rotate a flexible film, thereby driving the rotational polishing of the wafer. When a conventional flexible film is applied to an electrochemical process to drive wafer polishing, the flexible film rotates the conductive disc along with the polishing head as it rotates. Since the flexible film itself must withstand the tensile force generated when the polishing head rotates itself and when the polishing head scans the polishing pad by the polishing arm, safety accidents may occur if the flexible film ruptures due to excessive tensile force during the polishing process under harsh polishing conditions. Furthermore, in the conventional CMP polishing process, scratching occurs between the wafer and the polishing pad due to the tension of the flexible film during the start of polishing and the return of the flexible film when the polishing head finally stops operating and detaches from the polishing pad, which affects the polishing process.

[0004] To overcome the disadvantages of conventional technology, the present invention provides an electrochemical mechanical polishing and planarization device that utilizes a hard conductive disc to adsorb a wafer substrate under negative pressure and combines it with a conductive driving unit to achieve electrical conductivity. By performing conductive and mechanical driving functions, the conductive driving unit ensures stable electrochemical mechanical polishing of the wafer substrate while simultaneously extending the service life of the polishing head.

[0005] An electrochemical mechanical polishing and planarization device for solving the technical problem of the present invention comprises at least a polishing head, and the polishing head comprises the following:

[0006] Grinding head body;

[0007] A hard conductive disk having at least a portion of its lower surface located on the same surface to adsorb a wafer substrate;

[0008] A conductive driving unit, at least a portion of which can be connected to a power source and at least a portion of which is electrically coupled by contacting the hard conductive disk to drive the circumferential rotation of the hard conductive disk;

[0009] A movable 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] A retaining ring, which is an annular member located at the lower part of the polishing head body and capable of contacting the polishing pad, and a hard conductive disc move within an area defined by the retaining ring.

[0011] Furthermore, a pore is formed in a portion located on the same plane as the lower surface of the hard conductive disk, and the pore communicates with a third gas chamber within the hard conductive disk, and when the third gas chamber is in a negative pressure state, the hard conductive disk can adsorb a wafer substrate.

[0012] Furthermore, it further includes a second pressure-controllable gas chamber used to drive the up and down movement of a hard conductive disc.

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

[0014] Furthermore, the above-mentioned operating gap includes at least a radial operating gap and an axial operating gap.

[0015] Furthermore, the conductive drive unit includes a drive rod and a second drive member, the second drive member is connected to a hard conductive disc, and a first drive member is formed in the polishing head body to be electrically coupled to the second drive member, a movable gap is formed between the first drive member and the second drive member, and the second drive member maintains contact with the first drive member to achieve electrical conductivity.

[0016] Furthermore, the conductive driving unit comprises an electrically connected conductive block and a wire, wherein the conductive block is connected to a polishing head body, and the polishing head body drives the circumferential rotation of a hard conductive disc through the conductive block and transmits current to the hard conductive disc during driving; the hard conductive disc has a groove formed therein for inserting the conductive block, and a movable gap is formed between the conductive block and the groove.

[0017] Furthermore, the conductive blocks are spaced apart in multiple numbers along the polishing head body in a circumferential direction, and the conductive blocks maintain contact with the grooves to achieve electrical conductivity.

[0018] Furthermore, the number of the above-mentioned wires is one or equal to the number of conductive blocks, and when the number of wires is one, all conductive blocks are connected integrally through an annular body.

[0019] Furthermore, the conductive drive unit includes a drive rod and a second drive member, the drive rod is connected to an external power source, and a third drive member is formed on the hard conductive disc to be electrically coupled with the second drive member, and the movable gap is formed between the second drive member and the third drive member.

[0020] Furthermore, the conductive driving unit includes an elastic unit connected to the polishing head body and the hard conductive disk, respectively, thereby forming a structure in which the polishing head body, the elastic unit, and the hard conductive disk surround each other to form the second gas chamber.

[0021] Furthermore, the hard conductive disc is provided with a blocking jaw, the blocking jaw is inserted into the polishing head body and sealedly coupled through a sealing member to form the second gas chamber and a movable gap, and the blocking jaw is electrically connected to the polishing head body.

[0022] Furthermore, the rotational direction of the hard conductive disc is the same as or opposite to the rotational direction of the polishing head body.

[0023] Furthermore, the lower surface of the hard conductive disk is located on the same plane; or, a thickened area or a thinned area is formed on a portion of the lower surface of the hard conductive disk located on the same plane, thereby forming a height difference of nanometer level to micrometer level.

[0024] Furthermore, a flexible conductive fabric with holes formed therein is attached to the lower surface of the hard conductive disk, and the holes correspond to at least some pore locations of the hard conductive disk.

[0025] The beneficial effects of the present invention are as follows: 1) By using a hard conductive disc to electrically conduct between the polishing head and the wafer substrate to perform electrochemical mechanical polishing, the long-term stability of the electrochemical reaction can be ensured and the stability of the electrochemical mechanical polishing process can be improved; 2) By using a hard conductive disc to adsorb the wafer substrate under negative pressure, the problem of the flexible film being pulled and ruptured or changing its elastic modulus under harsh conditions when the flexible film drives the polishing of the wafer substrate is resolved, and the service life of the flexible member within the polishing head is extended; 3) By using a hard conductive disc to adsorb the wafer substrate under negative pressure, scratching between the wafer substrate and the polishing pad caused by the return of the flexible film during the process of the polishing head detaching from the polishing pad is prevented, thereby ensuring rapid and effective detachment of the wafer substrate from the polishing pad and ensuring the smooth progress of the polishing process; 4) When performing polishing of a wafer substrate using a flexible film as a driving member, if the force equilibrium state changes when encountering areas such as grooves on the polishing pad, it may affect the polishing speed and have an adverse effect on polishing efficiency; however, the rigid driving stability within the hard conductive disc is higher, so the above problem can be effectively prevented and process stability can be improved; 5) The conductive driving unit not only performs a conductive function but can also mechanically drive the hard conductive disc to perform the polishing process together with the wafer substrate; and since a space is provided for the hard conductive disc to float up and down and left and right due to the existence of a moving gap, the polishing becomes more flexible; 6) A self-control function of the rotation direction of the hard conductive disc can be implemented through the method of combining the blocking jaw and the polishing head body, and the direction can be the same as the rotation direction of the retaining ring and the hard conductive disc, or opposite to the rotation direction of the retaining ring and the hard conductive disc, thereby providing more possibilities for the polishing process. Brief explanation of the drawing

[0026] FIG. 1 is a perspective view of the three-dimensional structure of an electrochemical mechanical polishing and flattening device provided by the first embodiment of the present invention. FIG. 2 is a perspective view of the three-dimensional structure of an electrochemical mechanical polishing and flattening device provided by the first embodiment of the present invention. FIG. 3 is a perspective view of the three-dimensional structure of a hard conductive disk and an elastic unit provided by the first embodiment of the present invention. FIG. 4 is a cross-sectional structural perspective view of a hard conductive disk provided by the first embodiment of the present invention. FIG. 5 is a partial cross-sectional view of a hard conductive disk provided by the first embodiment of the present invention. FIG. 6 is a cross-sectional view of an electrochemical mechanical polishing and flattening apparatus provided by a first embodiment of the present invention. FIG. 7 is a perspective view of the three-dimensional structure of a hard conductive disk provided by the first embodiment of the present invention. FIG. 8 is a perspective view of the three-dimensional structure of a polishing head body provided by the first embodiment of the present invention. FIG. 9 is a perspective view of the three-dimensional structure of an electrochemical mechanical polishing and flattening device provided by a second embodiment of the present invention. FIG. 10 is a front view of an electrochemical mechanical polishing and flattening apparatus provided by a second embodiment of the present invention. FIG. 11 is a perspective view of the three-dimensional structure of a hard conductive disk and an elastic unit provided by a second embodiment of the present invention. FIG. 12 is a cross-sectional view 1 of an electrochemical mechanical polishing and flattening apparatus provided by a second embodiment of the present invention. FIG. 13 is a cross-sectional view 2 of an electrochemical mechanical polishing and flattening apparatus provided by a second embodiment of the present invention. FIG. 14 is a perspective view of the three-dimensional structure of a hard conductive disk and an elastic unit provided by the third embodiment of the present invention. FIG. 15 is a cross-sectional view of an electrochemical mechanical polishing and flattening apparatus provided by a third embodiment of the present invention. FIG. 16 is a perspective view of the combined structure of a hard conductive disk, a conductive driving unit, and an external power source provided by the third embodiment of the present invention. Figure 17 is an enlarged view of the structure at point A in Figure 16. FIG. 18 is a perspective view of the three-dimensional structure of a hard conductive disk provided by the third embodiment of the present invention. FIG. 19 is a cross-sectional view of an electrochemical mechanical polishing and flattening apparatus provided by the fourth embodiment of the present invention. FIG. 20 is a perspective view of the combined structure of a hard conductive disk and a conductive driving unit provided by the fourth embodiment of the present invention. FIG. 21 is a perspective view of the three-dimensional structure of a polishing head body provided by the fourth embodiment of the present invention. FIG. 22 is a cross-sectional view of an electrochemical mechanical polishing and flattening apparatus provided by the fifth embodiment of the present invention. FIG. 23 is a perspective view of the three-dimensional structure of a hard conductive disk provided by the fifth embodiment of the present invention. FIG. 24 is a cross-sectional view of an electrochemical mechanical polishing and flattening apparatus provided by the 6th embodiment of the present invention. FIG. 25 is a perspective view of the combined structure of a hard conductive disk, a conductive driving unit, and an external power source provided by the 6th embodiment of the present invention. FIG. 26 is a perspective view of the three-dimensional structure of a hard conductive disk provided by the sixth embodiment of the present invention. Specific details for implementing the invention

[0027] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution according to the embodiments of the present invention is described below clearly and completely in conjunction with the drawings included in the embodiments of the present invention. Clearly, the described embodiments are not all embodiments of the present invention, but only parts of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present invention.

[0028] First embodiment

[0029] As illustrated in FIGS. 1 and 2, an electrochemical mechanical polishing and flattening device comprises at least a polishing head, the polishing head comprising a polishing head body (1), a hard conductive disk (2), a conductive driving unit (3), a movable gap (4), and a retaining ring (5) located below the polishing head body (1).

[0030] A hard conductive disk (2) means that the conductive disk is manufactured from a hard material such as a metal, a conductive material, or other conductive material having rigidity. Specifically, the metal may be aluminum, titanium, or stainless steel, and other conductive materials may be conductive ceramics, graphite, etc. Since all of the above materials are conductive materials, the hard conductive disk (2) can form a conductive circuit necessary for a wafer substrate, a polishing platen, a power source, and electrochemical mechanical polishing. When power is applied to the hard conductive disk (2), current is transmitted to the wafer substrate to perform surface modification, and then mechanical polishing is performed. In this embodiment, the lower surface of the hard conductive disk (2) is all located on the same plane. Of course, in other embodiments, the planar roughness of the horizontal portion of the hard conductive disk (2) may be formed such that a specific area is formed thicker or thinner depending on the thickness shape of the wafer substrate. That is, it may be formed as a thickened area or a thinned area, thereby forming a height difference of nanometer level to micrometer level between different areas. In another embodiment, the sides of the hard conductive disk (2) may be insulated and chamfered, wherein the insulation treatment includes, but is not limited to, methods such as hard oxidation and surface coating.

[0031] In this embodiment, the hard conductive disk (2) has a disc-shaped structure as shown in FIG. 5. The upper surface of the hard conductive disk (2) is non-permeable, and at least a portion of the lower surface of the hard conductive disk (2) is located on the same plane, and a plurality of pores (21) are formed in the portion located on the lower surface on the same plane, and a third gas chamber (22) is formed inside the hard conductive disk (2) in communication with the pores (21). The third gas chamber (22) must use a sealed connection method to prevent the polishing head from being contaminated due to leakage of the polishing slurry, and other functions can be implemented through any connection method under conditions that do not affect the internal environment of the polishing head. For example, it can be implemented through sealing designs such as gas pipe connection, screw and seal ring connection of the device body, and flexible membrane chamber type structural design, and since this can be implemented with prior art, it is not described further. The diameter of the pores (21) is 0.1 to 3 mm, and the total area of ​​all pores (21) occupies 0.1 to 5% of the lower surface area of ​​the hard conductive disk (2). When negative pressure is formed in the third gas chamber (22), the lower surface of the hard conductive disk (2), more precisely, a part of the lower surface located on the same plane, can be adsorbed by directly contacting the wafer substrate.

[0032] In this embodiment, as shown in FIG. 4, all pores (21) are interconnected. Inside the hard conductive disk (2), a gas passage (25) is formed that is radially intersected and interconnected, and the gas passage (25) is connected to a third gas chamber (22), and the pores (21) are arranged corresponding to the area where the gas passage (25) is located. Thus, the negative pressure formed by all pores (21) is relatively balanced.

[0033] One of the logics for determining whether a wafer substrate is loaded into the polishing head body (1) is to make the third gas chamber (22) a vacuum and then perform a holding pressure test to check the vacuum state of the third gas chamber (22). If negative pressure is maintained, it is determined that the wafer substrate is loaded into the polishing head body (1), and if the opposite is true, it is determined that the wafer substrate is not loaded into the polishing head body (1).

[0034] The retaining ring (5) is an annular member capable of contacting the polishing pad, and the hard conductive disc (2) moves within the area defined by the retaining ring (5).

[0035] A first gas chamber (11) is formed within the polishing head body (1) and is used to control the vertical movement and lifting stroke of a part of the polishing head body (1), and further to move the hard conductive disk (2) and the wafer substrate up and down. The polishing head further includes a second gas chamber (6) capable of pressure control, and the second gas chamber (6) is used to drive the vertical movement of the hard conductive disk (2).

[0036] In this embodiment, the conductive driving unit (3) further includes an elastic unit (7) connected to the polishing head body (1) and the hard conductive disk (2), respectively. Specifically, as shown in FIG. 3, the elastic unit (7) is made of an elastic material and has a roughly annular structure, one side 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 retaining ring (5). The elastic unit (7) forms a structure that surrounds the polishing head body (1) and the hard conductive disk (2) to form a second gas chamber (6). Since the pressure inside the second gas chamber (6) is controllable, by controlling the internal pressure of the second gas chamber (6), elastic movement of the elastic unit (7) is generated to assist in the floating of the hard conductive disk (2) and the wafer substrate, thereby enabling electrochemical mechanical polishing of the wafer substrate. Here, the floating of the hard conductive disk (2) and the wafer substrate means improving the mobility of the hard conductive disk (2) and the wafer substrate using an elastic unit (7) under the premise of mechanical driving of the polishing head body (1) and the hard conductive disk (2), and the movement includes vertical floating and radial floating. The method of controlling the internal pressure of the second gas chamber (6) is conventional technology and is therefore not described further.

[0037] Of course, based on the fact that the circuit is connected directly from the power electrode to the hard conductive disk (2) in the electrochemical mechanical polishing and flattening of the wafer substrate, the circuit may also be connected from the elastic unit (7) to the hard conductive disk (2) to implement the function of the hard conductive disk (2), and is not specifically limited.

[0038] A portion of the conductive drive unit (3) may be extended from the polishing head body (1) and connected to a power source, and a portion of the conductive drive unit (3) may be in contact with and electrically coupled to the hard conductive disk (2), thereby driving the circumferential rotation of the hard conductive disk (2). Here, the power source is not specifically limited as long as it can implement power supply.

[0039] A movable gap (4) is formed between the polishing head body (1) and the conductive drive unit (3); or, a movable gap (4) is formed between the conductive drive unit (3) and the hard conductive disk (2); or, a movable gap (4) is formed between the hard conductive disk (2) and the polishing head body (1); or, a movable gap (4) is formed between the polishing head body (1) and the conductive drive unit (3), and simultaneously, a movable gap (4) is also formed between the conductive drive unit (3) and the hard conductive disk (2); or, a movable gap (4) is formed between the polishing head body (1) and the conductive drive unit (3), and simultaneously, a movable gap (4) is also formed between the hard conductive disk (2) and the polishing head body (1); or, a movable gap (4) is formed between the conductive drive unit (3) and the hard conductive disk (2), and simultaneously, a movable gap (4) is also formed between the hard conductive disk (2) and the polishing head body (1).

[0040] A conductive drive unit (3) includes a drive rod (31) and a second drive unit (32), and the second drive unit (32) is connected to a hard conductive disk (2), wherein the hard conductive disk (2) is integrally connected to the second drive unit (32) of the conductive drive unit (3); the drive rod (31) is connected to the hard conductive disk (2), wherein the hard conductive disk (2) is integrally connected to the drive rod (31). Of course, the drive rod (31) may also be connected to the second drive unit (32), wherein the hard conductive disk (2) is integrally connected to the drive rod (31) and the second drive unit (32).

[0041] A first drive unit (33) is formed in the polishing head body (1) and is electrically coupled with a second drive unit (32), and the movable gap (4) is formed between the first drive unit (33) and the second drive unit (32).

[0042] Specifically, as illustrated in FIGS. 6 to 8, the drive rod (31) has a hollow columnar structure, its lower end is integrally connected to the upper surface (one side where the pore (21) is not formed) of the hard conductive disk (2), and its upper end extends from the polishing head body (1); the second drive part (32) includes a plurality of fan-shaped protrusions spaced apart around the drive rod (31) and fixedly connected to the outer wall of the drive rod (31). Of course, the specific shape of the protrusions is not limited and may be square.

[0043] The first drive unit (33) is a groove structure into which the second drive unit (32) can be inserted. When the polishing head body (1) rotates in the circumferential direction, the circumferential rotation of the hard conductive disk (2) can be driven through the combination of the first drive unit (33) and the second drive unit (32). Since the cross-sectional area of ​​the first drive unit (33) is larger than the cross-sectional area of ​​the second drive unit (32), the second drive unit (32) is in close contact with the bottom of the groove of the first drive unit (33) to achieve electrical conductivity, and at the same time, the second drive unit (32) can also move in the radial direction within the first drive unit (33) (where the radial direction refers to the diameter direction of the hard conductive disk (2)). Alternatively, when power is connected to the first drive unit (33) and energized, the second drive unit (32) is in close contact with the side wall of the groove of the first drive unit (33) to achieve electrical conduction, and at the same time, the second drive unit (32) can also move in the axial direction within the first drive unit (33). That is, the second drive unit (32) is in close contact with at least the side wall or bottom wall of the first drive unit (33) to achieve electrical conduction.

[0044] Of course, in other embodiments, the first driving part (33) may be a protrusion and the second driving part (32) may be a groove, and is not specifically limited.

[0045] The radial movable gap (41) and the axial movable gap (42) between the first driving unit (33) and the second driving unit (32) are configured as a movable gap (4). That is, the movable gap (4) is formed between the polishing head body (1) and the conductive driving unit (3), thereby controlling the pressure in the second gas chamber (6) to generate elastic movement of the elastic unit (7), which can assist in the floating of the hard conductive disk (2) and the wafer substrate, and the floating occurs within the movable gap (4); the hard conductive disk (2) can form a conductive circuit necessary for the wafer substrate, the polishing platen, the power supply, and electrochemical mechanical polishing, and the current is transmitted to the hard conductive disk (2) through the driving rod (31) and then transmitted to the wafer substrate to perform surface modification, and subsequently, electrochemical mechanical polishing of the wafer substrate is implemented.

[0046] 2nd embodiment

[0047] As illustrated in FIGS. 9 to 11, in this embodiment, the conductive driving unit (3) includes an electrically connected conductive block (34) and a conductor (35), the conductive block (34) is connected to the polishing head body (1), and the hard conductive disk (2) forms a groove (23) into which the conductive block (34) can be inserted. That is, the hard conductive disk (2) and the conductive driving unit (3) are arranged separately. When the polishing head body (1) rotates in the circumferential direction, the circumferential rotation of the hard conductive disk (2) can be driven through the coupling of the conductive block (34) and the groove (23). Since the cross-sectional area of ​​the groove (23) is larger than the cross-sectional area of ​​the conductive block (34), the conductive block (34) is in close contact with the bottom of the groove (23) to achieve electrical conductivity, while the conductive block (34) can also move in the radial direction within the groove (23) (where the radial direction refers to the diameter direction of the hard conductive disk (2)). Alternatively, the conductive block (34) may be in close contact with the side wall of the groove (23) to achieve electrical conductivity, while the conductive block (34) may move axially within the groove (23). That is, the polishing head body (1) drives the circumferential rotation of the hard conductive disk (2) through the conductive block (34), transmits current to the hard conductive disk (2) during driving, and the conductive block (34) is in close contact with at least the side wall or bottom wall of the groove (23) to achieve electrical conductivity.

[0048] In this embodiment, the conductive blocks (34) are spaced apart in the circumferential direction along the polishing head body (1), and thus, the number of grooves (23) is equal to the number of conductive blocks (34). The number of conductors (35) is one or equal to the number of conductive blocks (34).

[0049] When the number of conductors (35) is one, all conductive blocks (34) are connected integrally through an annular body (36) as shown in FIGS. 12 and 13.

[0050] The radial movable gap (41) and the axial movable gap (42) between the conductive block (34) and the groove (23) are composed of a movable gap (4). That is, the movable 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), the movable gap (4) can be said to be formed between the hard conductive disk (2) and the polishing head body (1). By controlling the pressure in the second gas chamber (6) to generate elastic movement of the elastic unit (7), the buoyancy of the hard conductive disk (2) and the wafer substrate can be assisted, and the buoyancy occurs within the movable gap (4). The hard conductive disc (2) can form a conductive circuit necessary for a wafer substrate, a polishing platen, a power source, and electrochemical mechanical polishing, and the current is transmitted through the wire (35) to the conductive block (34) and then back to the wafer substrate to perform surface modification, and then electrochemical mechanical polishing of the wafer substrate is implemented.

[0051] Others are identical to the first embodiment and are therefore not described further.

[0052] Third embodiment

[0053] As illustrated in FIGS. 14 to 18, the conductive drive unit (3) includes a drive rod (31) and a second drive unit (32), the upper end of the drive rod (31) is connected to an external power source (312), and the external power source (312) may be a motor. A third drive unit (37) is formed in the hard conductive disk (2) to be electrically coupled with the second drive unit (32). That is, the hard conductive disk (2) and the conductive drive unit (3) are separated and arranged, and a movable gap (4) is formed between the second drive unit (32) and the third drive unit (37).

[0054] Specifically, the drive rod (31) has a columnar or hollow columnar structure, its lower end is integrally connected to the second drive unit (32), and its upper end extends from the grinding head body (1) and has an outer ring (311). The motor transmits power through the outer ring (311) to rotate the drive rod (31) in a circumferential direction, thereby rotating the second drive unit (32). The second drive unit (32) includes a plurality of fan-shaped protrusions spaced apart from the drive rod (31) and fixedly connected to the outer wall of the drive rod (31).

[0055] The third driving unit (37) is a groove structure formed on the upper surface (one side where the pore (21) is not formed) of the hard conductive disk (2), into which the second driving unit (32) is inserted. When the second driving unit (32) rotates in the circumferential direction, the circumferential rotation of the hard conductive disk (2) can be driven through the combination of the second driving unit (32) and the third driving unit (37).

[0056] Power is connected to the second drive unit (32) to provide power, and since the cross-sectional area of ​​the third drive unit (37) is larger than the cross-sectional area of ​​the second drive unit (32), the second drive unit (32) is in close contact with the bottom of the groove of the third drive unit (37) to provide electrical conduction, and at the same time, the second drive unit (32) can also move in the radial direction within the third drive unit (37) (wherein the radial direction refers to the diameter direction of the hard conductive disk (2)). Alternatively, the second drive unit (32) is in close contact with the side wall of the groove of the third drive unit (37) to provide electrical conduction, and at the same time, the second drive unit (32) can also move in the axial direction within the third drive unit (37). That is, the second drive unit (32) is in close contact with at least the side wall or bottom wall of the third drive unit (37) to provide electrical conduction.

[0057] Of course, in other embodiments, the third driving part (37) may be a protrusion and the second driving part (32) may be a groove, and is not specifically limited.

[0058] Since the radial movable gap (41) and the axial movable gap (42) between the third driving unit (37) and the second driving unit (32) are composed of a movable gap (4), the pressure in the second gas chamber (4) is adjusted to generate elastic movement of the elastic unit (7), thereby assisting in the floating of the hard conductive disk (2) and the wafer substrate, and the floating occurs within the movable gap (4); the hard conductive disk (2) can form a conductive circuit necessary for the wafer substrate, the polishing platen, the power supply, and electrochemical mechanical polishing, and the current is transmitted to the hard conductive disk (2) through the driving rod (31) and then transmitted to the wafer substrate to perform surface modification, and subsequently, electrochemical mechanical polishing of the wafer substrate is implemented.

[0059] Others are identical to the first embodiment and are therefore not described further.

[0060] 4th embodiment

[0061] As illustrated in FIGS. 19 to 21, the difference from the first embodiment is that the elastic unit (7) is not provided in this embodiment, and the hard conductive disk (2) further includes a blocking jaw (24) based on a disc-shaped structure. The blocking jaw (24) extends vertically from the outer ring toward the polishing head body (1), and the blocking jaw (24) is inserted into the polishing head body (1) and sealed through a sealing member (8) to form the second gas chamber (6) and the movable gap (4), and at the same time, the blocking jaw (24) is electrically connected to the polishing head body (1). That is, the circuit in the electrochemical mechanical polishing and flattening process of the wafer substrate is connected from the blocking jaw (24) to the hard conductive disk (2).

[0062] Specifically, an annular groove (12) is formed in the grinding head body (1) such that the radial width of one side is greater than the thickness of the blocking jaw (24), thereby forming a radial movable gap (41) within the movable gap (4). A sealing member (8) is fitted onto the side wall of the annular groove (12), and the outer wall of the blocking jaw (24) comes into contact with the sealing member (8) to achieve a sealing connection, allowing the blocking jaw (24) to float left and right within the annular groove (12). The depth of the annular groove (12) is greater than the height of the blocking jaw (24) inserted into the annular groove (12), thereby forming an axial movable gap (42) within the movable gap (4). That is, the blocking jaw (24) can float up and down within the annular groove (12).

[0063] In the same manner as in the first embodiment, the conductive drive unit (3) includes a drive rod (31) and a second drive unit (32), the second drive unit (32) is connected to a hard conductive disk (2), and a first drive unit (33) is formed in the polishing head body (1) to be electrically coupled with the second drive unit (32), and the movable gap (4) is formed between the first drive unit (33) and the second drive unit (32). That is, the movable gap (4) is formed between the conductive drive unit (3) and the hard conductive disk (2), and at the same time, the movable gap (4) is also formed between the hard conductive disk (2) and the polishing head body (1).

[0064] In this embodiment, since it is not limited by the elastic unit (7), the blocking jaw (24) can rotate at any angle within the annular groove (12). That is, the rotational direction of the hard conductive disk (2) may be the same as or opposite to the rotational direction of the polishing head body (1).

[0065] For example, to reduce wear on the retaining ring (5), the rotational direction of the retaining ring (5) and the hard conductive disk (2) may be the same. That is, the rotational direction of the hard conductive disk (2) and the polishing head body (1) is the same. If the rotational direction of the hard conductive disk (2) and the retaining ring (5) and the polishing head body (1) are opposite, the removal rate of the wafer substrate surface can be improved. Specifically, when the polishing platen rotates counterclockwise, the polishing removal rate is greatly improved as the hard conductive disk (2) rotates the wafer substrate clockwise. Other details are the same as those of the first embodiment and are therefore not described further.

[0066] Fifth embodiment

[0067] As illustrated in FIGS. 22 and 23, in this embodiment, the elastic unit (7) is not provided, and the hard conductive disk (2) further includes a blocking jaw (24) based on a disc-shaped structure. The specific coupling structure is the same as that of the fourth embodiment and is therefore not described further.

[0068] In the same manner as in the second embodiment, the conductive driving unit (3) includes an electrically connected conductive block (34) and a conductor (35), the conductive block (34) is connected to the polishing head body (1), and the hard conductive disc (2) forms a groove (23) into which the conductive block (34) can be inserted. When the polishing head body (1) rotates in a circumferential direction, the circumferential rotation of the hard conductive disc (2) can be driven through the coupling of the conductive block (34) and the groove (23). The radial movable gap (41) and the axial movable gap (42) between the conductive block (34) and the groove (23) are composed of a movable gap (4).

[0069] Of course, the positions of the conductive block (34) and the groove (23) can be interchanged. The conductive block (34) is connected to the hard conductive disk (2), and a groove (23) into which the conductive block (34) can be inserted is formed in the polishing head body (1), so that a movable gap (4) is formed between the polishing head body (1) and the conductive driving unit (3), and at the same time as the movable gap (4) is formed between the polishing head body (1) and the conductive driving unit (3), a movable gap (4) is also formed between the hard conductive disk (2) and the polishing head body (1).

[0070] Others are identical to the first embodiment and are therefore not described further.

[0071] 6th embodiment

[0072] As illustrated in FIGS. 24 to 26, in this embodiment, the elastic unit (7) is not provided, and the hard conductive disk (2) further includes a blocking jaw (24) based on a disc-shaped structure. The specific coupling structure is the same as that of the fourth embodiment and is therefore not described further.

[0073] In the same manner as in the third embodiment, the conductive drive unit (3) includes a drive rod (31) and a second drive unit (32), the upper end of the drive rod (31) is connected to an external power source (312), and a third drive unit (37) is formed on the hard conductive disk (2) to be electrically coupled with the second drive unit (32), and a movable gap (4) is formed between the second drive unit (32) and the third drive unit (37). Thus, a movable gap (4) is formed between the conductive drive unit (3) and the hard conductive disk (2), and at the same time, a movable gap (4) is also formed between the hard conductive disk (2) and the polishing head body (1).

[0074] Of course, the positions of the second drive unit (32) and the third drive unit (37) can be interchanged, and the structure of the second drive unit (32) can be placed on a hard conductive disk (2), and the structure of the third drive unit (37) can be placed on a conductive drive unit (3).

[0075] Others are identical to the first embodiment and are therefore not described further.

[0076] 7th embodiment

[0077] Based on the first and third embodiments, a radial gap and an axial gap are further provided between the outer wall of the drive rod (31) and the polishing head body (1), thereby forming a movable gap (4) between the polishing head body (1) and the conductive drive unit (3). At the same time, a movable gap (4) is also formed between the conductive drive unit (3) and the hard conductive disk (2).

[0078] 8th embodiment

[0079] In this embodiment, the lower surface of the hard conductive disk (2) has a resistivity of 10 -3 A flexible conductive fabric with a resistance of less than mΩ·cm is attached. Pores are formed in the flexible conductive fabric, and since the pores correspond to the positions of at least some of the pores (21) of the hard conductive disk (2), the gas flow path is smoother when the gas chamber (3) is pressurized or vacuum treatment is performed, and it is more advantageous for the adsorption of the wafer substrate during vacuum treatment of the gas chamber (3).

[0080] Other structures are identical to any one of the first to seventh embodiments, so they are not described further.

[0081] The specific embodiments described above are not limitations to the invention, but merely descriptions thereof. Within the spirit and scope of the claims, all modifications and changes to the invention are included within the scope of protection of the invention. Explanation of the symbols

[0082] 1-Grinding head body, 11-First gas chamber, 12-Annular groove, 2-Hard conductive disc, 21-Pore, 22-Third gas chamber, 23-Groove, 24-Blocking jaw, 25-Gas flow path, 3-Conductive driving unit, 31-Driving rod, 311-External ring, 312-External power, 32-Second driving part, 33-First driving part, 34-Conductive block, 35-Wire, 36-Annular body, 37-Third driving part, 4-Mounting gap, 41-Radical moving gap, 42-Axial moving gap, 5-Retaining ring, 6-Second gas chamber, 7-Elastic unit, 8-Sealing member.

Claims

Claim 1 An electrochemical mechanical polishing and flattening device comprising at least a polishing head, wherein the polishing head comprises: a polishing head body (1); a hard conductive disk (2) having at least a portion of its lower surface located on the same surface to adsorb a wafer substrate; a conductive driving unit (3) having at least a portion connected to a power source and at least a portion electrically coupled to contact the hard conductive disk (2) to drive the circumferential rotation of the hard conductive disk (2); a movable gap formed between the polishing head body (1) and the conductive driving unit, and / or formed between the conductive driving unit (3) and the hard conductive disk (2), and / or formed between the hard conductive disk (2) and the polishing head body (1); and a retaining ring which is an annular member located below the polishing head body (1) and capable of contacting a polishing pad, wherein the hard conductive disk (2) moves within an area defined by the retaining ring (5). Claim 2 The electrochemical mechanical polishing and flattening apparatus is characterized in that, in the first paragraph, a pore (21) is formed in a portion located on the same plane as the lower surface of the hard conductive disk (2), and the pore (21) is in communication with a third gas chamber (22) within the hard conductive disk (2), and when the third gas chamber (22) is in a negative pressure state, the hard conductive disk (2) can adsorb a wafer substrate. Claim 3 The electrochemical mechanical polishing and flattening apparatus according to claim 1, further comprising a pressure-controllable second gas chamber (6) used to drive the up and down movement of a hard conductive disk (2). Claim 4 An electrochemical mechanical polishing and flattening apparatus characterized in that, in paragraph 3, the hard conductive disk (2) and the conductive driving unit (3) are connected integrally, or the hard conductive disk (2) and the conductive driving unit (3) are arranged separately. Claim 5 The electrochemical mechanical polishing and flattening apparatus according to claim 3, wherein the movable gap (4) comprises at least a radial movable gap (41) and an axial movable gap (42). Claim 6 In paragraph 3, the conductive driving unit (3) includes a driving rod (31) and a second driving unit (32), the second driving unit (32) is connected to a hard conductive disc (2), and a first driving unit (33) is formed in the polishing head body (1) to be electrically coupled with the second driving unit (32), and a movable gap (4) is formed between the first driving unit (33) and the second driving unit (32), and the second driving unit (32) maintains contact with the first driving unit (33) to achieve electrical conductivity; characterized in that the electrochemical mechanical polishing and flattening device. Claim 7 In paragraph 3, the conductive driving unit (3) comprises an electrically connected conductive block (34) and a conductor (35), wherein the conductive block (34) is connected to a polishing head body (1), and the polishing head body (1) drives the circumferential rotation of a hard conductive disk (2) through the conductive block (34) and transmits current to the hard conductive disk (2) during driving; the hard conductive disk (2) has a groove (23) formed so that the conductive block (34) is inserted, and the movable gap (4) is formed between the conductive block (34) and the groove (23); characterized in that the electrochemical mechanical polishing and flattening device. Claim 8 In claim 7, the electrochemical mechanical polishing and flattening apparatus is characterized in that a plurality of conductive blocks (34) are spaced apart in the circumferential direction along the polishing head body (1), and the conductive blocks (34) maintain contact with the groove to achieve electrical conductivity. Claim 9 An electrochemical mechanical polishing and flattening apparatus characterized in that, in claim 7, the number of conductors (35) is one or equal to the number of conductive blocks (34), and when the number of conductors (35) is one, all conductive blocks (34) are integrally connected through an annular body (36). Claim 10 In paragraph 3, the conductive driving unit (3) comprises a driving rod (31) and a second driving unit (32), the driving rod (31) is connected to an external power source, a third driving unit (37) is formed on the hard conductive disk (2) to be electrically coupled with the second driving unit (32), and a movable gap (4) is formed between the second driving unit (32) and the third driving unit (37); characterized in that the electrochemical mechanical polishing and flattening device. Claim 11 The electrochemical mechanical polishing and flattening apparatus is characterized in that, in claim 6, 7, or 10, the conductive driving unit (3) includes an elastic unit (7) connected to the polishing head body (1) and the hard conductive disk (2), respectively, thereby forming a structure in which the polishing head body (1), the elastic unit (7), and the hard conductive disk (2) surround each other to form the second gas chamber (6). Claim 12 The electrochemical mechanical polishing and flattening apparatus according to claim 6, 7, or 10, wherein the hard conductive disc (2) is provided with a blocking jaw (24), the blocking jaw (24) is inserted into the polishing head body (1) and sealed through a sealing member (8) to form the second gas chamber (6) and the movable gap (4), and the blocking jaw (24) is electrically connected to the polishing head body (1). Claim 13 The electrochemical mechanical polishing and flattening apparatus according to claim 12, wherein the rotational direction of the hard conductive disk (2) is the same as or opposite to the rotational direction of the polishing head body (1). Claim 14 An electrochemical mechanical polishing and flattening apparatus according to claim 1 or 2, wherein the lower surface of the hard conductive disk (2) is located on the same plane; or, a thickened area or a thinned area is formed on a part of the lower surface of the hard conductive disk (2) located on the same plane to form a height difference of nanometer level to micrometer level. Claim 15 The electrochemical mechanical polishing and flattening apparatus according to claim 2, wherein a flexible conductive fabric with holes formed therein is attached to the lower surface of the hard conductive disk (2), and the holes correspond to at least some pore (21) locations of the hard conductive disk (2).

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