An electropolishing head, conductive system and assembly method for electrochemical mechanical planarization equipment

Abstract

The present invention discloses an electropolishing head, a conductive system and an assembly method thereof for an electrochemical mechanical planarization device. The electropolishing head includes a conductive member, which is inserted into a polishing head carrier and is used to connect an external power supply unit; a conductive column, which is inserted into the polishing head or the polishing head carrier and at least includes a shell, a telescopic member, and a conductive probe. The conductive probe and the shell are respectively connected to the telescopic member so that the conductive probe and the shell can slide relative to each other along the axial direction, and the outer wall of the conductive probe contacts and conducts electricity with the inner wall of the shell, so that sliding contact conduction is formed between the conductive probe and the shell; a conductive column connecting unit is provided on the polishing head and is detachably connected to the conductive column. In the present invention, a conductive device in the form of sliding contact is used in a limited and confined space to tightly connect the conductive structures of two adjacent components, so that electric energy can be efficiently transmitted between adjacent components.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor processing, and in particular relates to an electropolishing head, a conductive system and an assembly method thereof for electrochemical mechanical planarization equipment. Background Art

[0002] Chemical Mechanical Planarization (CMP) equipment usually includes a semiconductor equipment front-end module (EFEM), a cleaning unit, and a polishing unit. In the polishing unit, the wafer is chemically mechanically polished or planarized on the polishing pad by adjusting parameters such as the pressure applied by the polishing head to the wafer, the speed of the polishing head, and the speed of the polishing disk.

[0003] The existing electrochemical mechanical polishing planarization process applies electrical energy to the wafer surface and utilizes the conductivity of the wafer substrate or its surface film to carry out an electrochemical reaction on the wafer substrate or its surface film, thereby increasing its chemical reaction rate and improving the efficiency of the wafer chemical mechanical planarization process.

[0004] In the context of electrochemical mechanical planarization, the polishing head needs to add the function of applying electrical energy to the wafer substrate or the thin film on the wafer surface in addition to the basic functions of clamping, placing, pressing, and rotating the wafer. The current technology uses ordinary conductive cables to conduct electricity inside the polishing head structure in the electrochemical mechanical planarization process. This solution will cause difficulties in installing the conductive cables of some structures, and the connection between the conductive cables and the structure will be damaged due to long-term bending. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides an electropolishing head, a conductive system and an assembly method thereof for an electrochemical mechanical planarization device, which ensures the conduction of an internal circuit, realizes efficient power transmission, and has a simple and stable installation structure.

[0006] The technical solution adopted by the present invention to solve the technical problem is: an electropolishing head for an electrochemical mechanical planarization device, comprising:

[0007] A conductive member, which is passed through the polishing head bearing member and is used to connect to an external power supply unit;

[0008] The conductive column is inserted into the polishing head or the polishing head bearing member, and at least comprises a housing, a telescopic member, and a conductive probe. The conductive probe and the housing are respectively connected to the telescopic member, so that the conductive probe and the housing can slide relative to each other in the axial direction, and the outer wall of the conductive probe contacts the inner wall of the housing and conducts electricity, so that sliding contact conduction is formed between the conductive probe and the housing;

[0009] The conductive column connecting unit is arranged on the polishing head and is detachably connected to the conductive column.

[0010] Furthermore, the conductive member is connected to the conductive column and is used to guide the electrical energy to the conductive column.

[0011] Furthermore, the telescopic member is axially assembled in the housing, and the conductive probe is axially inserted in the housing, with an end face abutting against the telescopic member.

[0012] Furthermore, the conductive probe, the telescopic member and the housing are coaxially and concentrically arranged.

[0013] Furthermore, the conductive probe head is provided with a conductive connector, the conductive connector forms a limiting groove, and the conductive probe end forms a terminal that can be limitedly matched with the limiting groove.

[0014] Furthermore, the conductive column connection unit includes a conductive structure matched with the polishing head, a flexible cable, and a conductive column connector, the conductive column connector is detachably connected to the conductive column, and the flexible cable is electrically connected to the conductive structure and the conductive disk in the polishing head respectively.

[0015] Furthermore, the number of the flexible cables is one or two or more; the polishing head is formed with a cavity, and the flexible cable is bent and accommodated in the cavity.

[0016] Furthermore, the conductive column connecting unit includes a conductive column connecting piece which can be detachably connected to the conductive disk.

[0017] Furthermore, a threaded section is provided at the end of the conductive column, which is threadedly connected to the conductive column connecting unit to increase the contact area for transmitting electrical energy.

[0018] The present invention also discloses a conductive system for an electrochemical mechanical planarization device, comprising:

[0019] Power supply unit;

[0020] An electropolishing head as described above;

[0021] Wafer;

[0022] The conductive member, conductive column and conductive disk of the electropolishing head are connected to the power supply unit, so that when the polishing head presses the wafer on the conductive disk, the power supply unit, the electropolishing head, the wafer and the conductive disk form a conductive path.

[0023] Furthermore, the polishing head has a connector, or the polishing head carrier has a connector, and the conductive column is inserted through the connector.

[0024] The present invention further discloses a method for assembling a conductive system for an electrochemical mechanical planarization device, comprising the following steps:

[0025] The conductive member is inserted into the circuit channel inside the polishing head bearing member, and one end of the conductive member is fixed to the conductive member connecting member inside the polishing head bearing member;

[0026] Fixing the conductive column housing to the conductive column connecting piece;

[0027] Fixing the conductive column connector to the conductive structural part inside the polishing head;

[0028] Fix one end of the flexible cable to the conductive structure inside the polishing head, and fix the other end of the flexible cable to the conductive disk;

[0029] The conductive disk is fixedly mounted on the polishing head, and the conductive film is fixedly mounted on the conductive disk;

[0030] The polishing head is fixedly assembled with the polishing head bearing member, the telescopic member of the conductive column abuts against the conductive probe, and the end of the conductive probe is closely fitted to the conductive member connecting member to achieve conduction.

[0031] The beneficial effects of the present invention are: 1) In a limited and enclosed space, a conductive device in the form of sliding contact is used to tightly connect the conductive structures of two adjacent components (polishing head carrier and polishing head), so that electric energy can be efficiently transmitted between adjacent components; 2) The sliding and tightly contact connection form of the conductive column, the conductive probe and the conductive column shell and the setting of the telescopic part in the conductive column are utilized to efficiently transmit electric energy between the conductive column, the conductive probe and the conductive column shell and the conductive parts and conductive column connecting parts connected to them respectively. The conductive column is connected through the shell and the conductive column connecting unit in close cooperation to achieve efficient transmission of electric energy; 3) The conductive column includes a separable shell, a telescopic part, and a conductive probe, which simplifies the assembly structure, and the conductive part can be installed in the polishing head more conveniently and quickly, and it is convenient to assemble and connect the polishing head and the carrier, thereby improving the installation efficiency of the electropolishing head in the electrochemical process. The shell, the telescopic part, and the conductive probe are non-rigidly connected, which improves the fault tolerance of the conductive structure and can be more convenient and simple. The invention can be used to clean the assembly or disassembly process; 4) the conductive column and the conductive column connection unit can be detachably connected to facilitate the assembly of the overall structure; 5) the threaded section structure at the end of the conductive column not only increases the connection strength, so that the conductive column and the conductive column connection unit can be stably assembled and connected, but also increases the contact area between the two to achieve more efficient power transmission; 6) the conductive column connection unit includes a flexible cable, which can be bent and accommodated in the cavity, providing a flexible space for the assembly connection of the conductive disk and the polishing head, reducing the difficulty of assembly; 7) compared with ordinary cables for conduction, the conductive column structure is used to reduce the space occupied by the conductive structure and the risk of bending and strain of ordinary cables, and the safety performance is higher; 8) multiple components are used to cooperate with each other to form a conductive path. When a problem occurs in the circuit, only some of the components need to be replaced, reducing the cost of using the conductive path; for different process chambers or use environments, some of the components can be updated or replaced more conveniently, reducing the cost of updating the conductive path. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A cross-sectional view of the electropolishing head provided by the present invention Figure 1 .

[0033] Figure 2 A partial cross-sectional view of the electropolishing head provided by the present invention Figure 1 .

[0034] Figure 3 This is a schematic diagram of the exploded structure of the conductive probe, telescopic member and housing provided by the present invention.

[0035] Figure 4 This is an exploded view of the installation of the electropolishing head provided by the present invention.

[0036] Figure 5A cross-sectional view of the electropolishing head provided by the present invention Figure 2 .

[0037] Figure 6 A partial cross-sectional view of the electropolishing head provided by the present invention Figure 2 .

[0038] Figure 7 A simplified diagram of the conductive system provided by the present invention.

[0039] Among them, 1-polishing head, 11-polishing head carrier, 111-circuit channel, 12-conductive disk, 13-connecting part, 14-cavity, 15-conductive film, 16-gas channel, 2-conductive part connecting part, 21-limiting groove, 3-conductive column, 31-housing, 32-telescopic part, 33-conductive probe, 331-conductive probe end, 34-threaded section, 4-conductive column connecting unit, 41-conductive structural part, 42-flexible cable, 421-flexible cable mounting part, 43-conductive column connecting part, 5-conductive part, 6-external power supply unit, 61-power switching device, 7-wafer, 8-hoop. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the solutions of the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0041] like Figure 1 As shown, an electropolishing head for an electrochemical mechanical planarization device includes a conductive connector 2 arranged on a polishing head carrier 11, a conductive column 3 arranged on the polishing head 1 or on the polishing head carrier 11, and a conductive column connecting unit 4 arranged on the polishing head 1, and the conductive column connecting unit 4 is detachably connected to the conductive column 3.

[0042] The conductive member connector 2 is connected to a conductive member 5, which is inserted into the circuit channel 111 inside the polishing head carrier 11. The conductive member 5 is connected to the external power supply unit 6 to guide the electric energy to the conductive member connector 2, that is, to transmit the external electric energy to the inside of the polishing head 1. Of course, in other embodiments, the conductive member connector 2 can also be directly connected to the external power supply unit 6, which is not specifically limited. Of course, the conductive member connector 2 can also be omitted, and the conductive member 5 can be directly connected to the external power supply unit 6 and the conductive column 3 to guide the electric energy to the conductive column 3.

[0043] The polishing head carrier 11 is a conductive metal structure, so the conductive member 5 is often wrapped with an insulating structure to prevent leakage.

[0044] The conductive column 3 at least includes a housing 31, a telescopic member 32, and a conductive probe 33. The conductive probe 33 and the housing 31 are respectively connected to the telescopic member 32, so that the conductive probe 33 and the housing 31 can slide relative to each other along the axial direction. Figure 6 As shown, the outer wall of the conductive probe 33 contacts and conducts electricity with the inner wall of the housing 31, so that a sliding contact type conduction is formed between the conductive probe 33 and the housing 31. When the conductive connector 2 is provided, the conductive probe 31 abuts against the conductive connector 2, or in other words, the head of the conductive probe 33 and the conductive connector 2 are integrally connected.

[0045] like Figure 3 As shown, during the assembly process of the conductive column 3, the telescopic member 32 is first placed inside the shell 31, and then the conductive probe 33 is axially installed inside the shell 31. At this time, the upper end of the telescopic member 32 is against the lower end of the conductive probe 33, and the lower end of the telescopic member 32 is against the bottom of the shell 31. In particular, a snap-on assembly can be provided inside the shell 31 and outside the conductive probe 33 to prevent the conductive column 3 from dispersing due to external force or the force of the internal telescopic member 32 after assembly.

[0046] Therefore, when the polishing head 1 presses the wafer 7 located on the conductive disk 12, the power supply unit 6, the conductive part connector 2, the conductive column 3, the conductive column connecting unit 4, the wafer 7, and the conductive disk 12 can form a conductive path, and because the telescopic part 32 of the conductive column 3 presses the conductive part connector 2 upward and presses the conductive column connecting unit 4 downward, a stable connection is formed at both ends of the conductive column 3, thereby ensuring that the circuit is effectively conductive.

[0047] Specifically, Figure 2 As shown, the shell 31 is hollow inside, the telescopic member 32 is axially assembled in the shell 31, the conductive probe 33 is axially inserted in the shell 31, and the end face of the conductive probe 33 is in contact with the end of the telescopic member 32. And the conductive probe 33, the telescopic member 32, and the shell 31 are concentrically and coaxially arranged. A threaded section 34 is provided at the end of the conductive column 3. Specifically, a threaded section 34 is provided at the end of the shell 31, and the threaded section 34 is concentrically and coaxially arranged with the conductive probe 33, the telescopic member 32, and the shell 31. The threaded section 34 is threadedly connected to the conductive column connecting unit 4, thereby increasing the contact area between the two to better transmit electrical energy, and the threaded section 34 can support the conductive column 3 to be stably and reliably fixed to the conductive column connecting member 43 inside the polishing head 1.

[0048] In order to ensure the stability of the connection between the conductive connector 2 and the conductive column 3 and prevent the two from deviating from each other, a limiting groove 21 is formed on the side of the conductive connector 2 facing the conductive column 3, and a terminal 331 is formed at the top end of the conductive probe 33. The terminal 331 can be extended into the limiting groove 21, and the two form a limiting fit.

[0049] like Figure 1 , Figure 4 As shown, the conductive column connection unit 4 includes a conductive structure 41 matched with the polishing head 1, a flexible cable 42, and a conductive column connection member 43, the conductive column connection member 43 is detachably connected to the conductive column 3, and the flexible cable 42 is electrically connected to the conductive structure 41 and the conductive plate 12 in the polishing head 1. The conductive column connection unit 4 passes through the upper and lower surfaces of the polishing head 1, and transmits the electrical energy from the conductive column connection member 43 to the flexible cable 42.

[0050] Here, the matching of the conductive structure 41 with the polishing head 1 means that part of the conductive structure 41 extends into the polishing head 1 , or part of the conductive structure 41 not only extends into the polishing head 1 but is also fixedly assembled and connected with the polishing head 1 .

[0051] In this embodiment, the longitudinal section of the conductive structure 41 is in an inverted T shape. The polishing head 1 is formed with a cavity 14, and the longitudinal portion of the conductive structure 41 is inserted into the polishing head 1, and its transverse portion is in contact with the top surface of the cavity 14, and one end of the flexible cable 42 is fixedly connected to the transverse portion through a mounting member 421, and can be conductive, and the other end of the flexible cable 42 is also fixedly connected to the conductive disk 12 through a mounting member and can be conductive, and the conductive disk 12 transmits the electrical energy from the flexible cable 42 to the conductive film 15, and the conductive film 15 is in close contact with the wafer 7 during the process, and transmits electrical energy to the surface of the wafer 7. The flexible cable 42 is bent and accommodated in the cavity 14, that is, the flexible cable 42 is in a retractable state. There is no limit on the number of flexible cables 42, which can be one or two or more, which can meet the requirements of large current processes and support the passage of larger electrical energy.

[0052] The longitudinal end of the conductive structure 41 is detachably connected to the conductive column connector 43 , and the conductive column connector 43 is detachably connected to the threaded section 34 of the conductive column 3 .

[0053] After assembly is completed, the top of the conductive probe 33 abuts against the conductive connector 2 to achieve effective conduction between the conductive column 3 and the conductive connector 2; the conductive structural member 41 abuts against the flexible cable 42 to achieve effective conduction between the conductive column connection unit 4 and the conductive disk 12.

[0054] like Figure 5 As shown, the situation that the conductive connector 2 and the end 331 of the conductive probe 33 are integrally connected is not excluded.

[0055] like Figure 7 As shown, a conductive system for an electrochemical mechanical planarization device includes a power supply unit 6, the electropolishing head as described above, and a wafer 7. The conductive connector 2, the conductive column 3, and the conductive disk 12 of the electropolishing head are connected to the power supply unit 6, so that when the polishing head 1 presses the wafer 7 located on the conductive disk 12, the power supply unit 6, the electropolishing head, the wafer 7, and the conductive disk 12 form a conductive path.

[0056] The on and off of the power supply unit 6 is controlled by the power switching device 61. During the process, the gas enters the cavity 14 through the gas path 16, and the gas pressure is transmitted to the conductive film 15 and applied to the surface of the wafer 7, so that the wafer 7 is closely attached to the conductive disk 12. The electric energy is transmitted to the wafer 7 through the following components in the positive or negative path: the conductive part 5, the conductive part connector 2, the conductive column 3, the conductive column connector 43, the conductive structural part 41, the flexible cable 42, the conductive disk 12, and the conductive film 15. The chemical liquid participates in the process flow and completes the electrochemical mechanical planarization process together with the above steps.

[0057] In this embodiment, the polishing head 1 has a connector 13, or more specifically, the polishing head carrier 11 has a connector 13, and the conductive column 3 is inserted into the connector 13. The connector 13 is used to rigidly connect the polishing head carrier 11 with the polishing head 1, and a circuit channel 111 is also provided inside the connector 13.

[0058] More specifically, the conductive connector 2 can be fixedly connected inside the polishing head carrier 11, and the conductive structure 41 can be fixed inside the polishing head 1. The polishing head 1 and the polishing head carrier 11 can also be tightly connected along the circumference through a clamp 8.

[0059] A method for assembling a conductive system for an electrochemical mechanical planarization device comprises the following steps:

[0060] like Figure 4 As shown, the conductive connector 2 is fixed inside the polishing head carrier 11, and the conductive structure 41 is fixed inside the polishing head 1;

[0061] The conductive member 5 is inserted into the circuit channel 111 inside the polishing head carrier 11, and one end of the conductive member 5 is fixed to the conductive member connector 2 inside the polishing head carrier 11;

[0062] The outer shell 31 of the conductive column 3 is fixed on the conductive column connecting piece 43; specifically, the two are connected by a threaded structure, that is, the threaded section 34 of the outer shell 31 is threadedly connected with the conductive column connecting piece 43;

[0063] The conductive column connector 43 is fixed to the conductive structure 41 inside the polishing head 1; specifically, the conductive column connector 43 and the conductive structure 41 are connected using a threaded structure;

[0064] Fix one end of the flexible cable 42 to the conductive structure 41 inside the polishing head 1 through the mounting member 421, and fix the other end of the flexible cable 42 to the conductive plate 12 through the mounting member 421;

[0065] The conductive plate 12 is fixedly mounted on the bottom of the polishing head 1, and the flexible cable 42 is bent and accommodated in the cavity 14, and the conductive film 15 is fixedly mounted on the conductive plate 12;

[0066] The polishing head 1 is fixedly assembled with the polishing head bearing member 11, the telescopic member 32 of the conductive column 3 abuts against the conductive probe 33, and the end of the conductive probe 33 is tightly fitted on the conductive member connector 2, so as to achieve conduction, so that the conductive member connector 2 can efficiently conduct the electrical energy from the conductive member 5 to the conductive column 3;

[0067] The polishing head 1 and the polishing head bearing 11 are tightly connected by the clamp 8, so that the gas path and the circuit between the polishing head 1 and the polishing head bearing 11 can be stably connected. The above specific embodiments are used to explain the present invention, rather than to limit the present invention. Any modifications and changes made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims

1. An electropolishing head for an electrochemical mechanical planarization device, characterized in that: include, A conductive member (5) is provided through the polishing head bearing member (11) and is used for connecting to an external power supply unit (6); The conductive column (3) is inserted into the polishing head (1) or the polishing head bearing member (11), and comprises at least a shell (31), a telescopic member (32), and a conductive probe (33). The conductive probe (33) and the shell (31) are respectively connected to the telescopic member (32), so that the conductive probe (33) and the shell (31) can slide relative to each other in the axial direction, and the outer wall of the conductive probe (33) contacts and conducts electricity with the inner wall of the shell (31), so that sliding contact type conduction is formed between the conductive probe (33) and the shell (31); the head of the conductive probe (33) is provided with a conductive member connecting member (2), the conductive member connecting member (2) forms a limiting groove (21), and the end of the conductive probe (33) forms an end head (331) that can be limitedly matched with the limiting groove (21); the end of the conductive column (3) is provided with a threaded section (34), which is threadedly connected to the conductive column connecting unit (4) to increase the contact area for transmitting electric energy; A conductive column connection unit (4), provided on the polishing head (1) and detachably connected to the conductive column (3); The conductive column connection unit (4) comprises a conductive structure (41) matched with the polishing head (1), a flexible cable (42), and a conductive column connection member (43); the conductive column connection member (43) is detachably connected to the conductive column (3); the flexible cable (42) is electrically connected to the conductive structure (41) and the conductive disk (12) in the polishing head (1), respectively; the number of the flexible cables (42) is one or two or more; the polishing head (1) is formed with a cavity (14), and the flexible cable (42) is bent and accommodated in the cavity (14), so as to provide a telescopic space for the assembly connection of the conductive disk (12) and the polishing head (1).

2. The electropolishing head for electrochemical mechanical planarization equipment according to claim 1, characterized in that: The conductive member (5) is connected to the conductive column (3) and is used to guide electrical energy to the conductive column (3).

3. The electropolishing head for electrochemical mechanical planarization equipment according to claim 1, characterized in that: The telescopic member (32) is axially assembled in the housing (31), and the conductive probe (33) is axially inserted in the housing (31), with its end face abutting against the telescopic member (32).

4. The electropolishing head for electrochemical mechanical planarization equipment according to claim 3, characterized in that: The conductive probe (33), the telescopic member (32), and the housing (31) are coaxially arranged.

5. The electropolishing head for electrochemical mechanical planarization equipment according to claim 1, characterized in that: The head of the conductive probe (33) is provided with a conductive component connector (2), the conductive component connector (2) forms a limiting groove (21), and the end of the conductive probe (33) forms a terminal head (331) that can be limitedly matched with the limiting groove (21).

6. The electropolishing head for electrochemical mechanical planarization equipment according to claim 1, characterized in that: The conductive column connection unit (4) comprises a conductive column connection piece which can be detachably connected to the conductive plate (12).

7. A conductive system for an electrochemical mechanical planarization device, characterized in that: comprising, a power supply unit (6); The electropolishing head according to any one of claims 1 to 6; Wafer (7); The conductive member (5), conductive column (3) and conductive disk (12) of the electropolishing head are connected to a power supply unit (6), so that when the polishing head (1) presses a wafer (7) located on the conductive disk (12), the power supply unit (6), the electropolishing head, the wafer (7) and the conductive disk (12) form a conductive path.

8. The conductive system for electrochemical mechanical planarization equipment according to claim 7, characterized in that: The polishing head (1) is provided with a connecting piece (13), or the polishing head carrier (11) is provided with a connecting piece (13), and the conductive column (3) is passed through the connecting piece (13).

9. A method for assembling a conductive system for an electrochemical mechanical planarization device, characterized in that: The following steps are involved: The conductive member is inserted into the circuit channel inside the polishing head bearing member, and one end of the conductive member is fixed to the conductive member connecting member inside the polishing head bearing member; Fixing the conductive column housing to the conductive column connecting piece; Fixing the conductive column connector to the conductive structural part inside the polishing head; Fix one end of the flexible cable to the conductive structure inside the polishing head, and fix the other end of the flexible cable to the conductive disk; The conductive disk is fixedly mounted on the polishing head, and the conductive film is fixedly mounted on the conductive disk; The polishing head is fixedly assembled with the polishing head bearing member, the telescopic member of the conductive column abuts against the conductive probe, and the end of the conductive probe is closely fitted to the conductive member connecting member to achieve conduction.

Images