Conductive gasket, base assembly and plasma etching equipment
By introducing a combination structure of flexible conductor and insulating liner into the conductive pad, the arcing problem caused by poor contact between the electrostatic adsorption chuck and the conductive pad is solved, thus achieving stable operation of the plasma etching equipment and substrate protection.
Patent Information
- Application Number
- CN202423245061.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2034-12-26
AI Technical Summary
In existing inductively coupled plasma etching equipment, poor contact between the electrostatic adsorption chuck and the conductive pad often generates electric arcs, leading to abnormal equipment shutdowns and substrate damage.
The conductive pad is composed of a flexible and slender conductor and an insulating inner liner. The conductor has an axially continuous inner cavity, and the insulating inner liner is inserted inside the conductor to ensure that the conductive pad is installed flat in the mounting groove, and the electrostatic adsorption chuck makes uniform contact with the conductive pad.
This reduces or even eliminates the arcing phenomenon between the electrostatic adsorption chuck and the conductive pad, improving the operational stability of the equipment and the safety of the substrate.
Smart Images
Figure CN223651352U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of semiconductor equipment technology, specifically relating to a conductive pad, a base assembly, and a plasma etching device. Background Technology
[0002] In semiconductor manufacturing processes, etching is typically used to form a thin film layer with a defined pattern on the substrate. Plasma etching is a commonly used etching method. Inductively coupled plasma etching equipment is a widely used type of plasma etching equipment.
[0003] In a prior art inductively coupled plasma etching (ICP-CPE) apparatus, a vacuum chamber is configured with an upper electrode and a base assembly arranged vertically opposite each other. The base assembly includes a conductive disk, an electrostatic chuck, and a conductive pad. The electrostatic chuck is disposed on the upper surface of the conductive disk, and a conductive pad is placed between the electrostatic chuck and the conductive disk. During operation, the upper electrode is connected to an external radio frequency (RF) source via an RF rod, and the conductive disk is connected to another external RF source via another RF rod. The upper electrode receives RF energy from the corresponding RF source to dissociate the process gas located between the upper electrode and the conductive disk, generating plasma. The conductive disk receives RF energy from the corresponding RF source to provide a traction force to the plasma, enabling the plasma to etch the wafer adsorbed on the electrostatic chuck. However, poor contact often occurs between the electrostatic chuck and the conductive pad, resulting in arcing, which makes it difficult for the equipment to operate normally and may even damage the electrostatic chuck and the substrate. Utility Model Content
[0004] The purpose of this invention is to provide a conductive pad, a base assembly, and a plasma etching device, which aims to reduce the phenomenon of electric arcing caused by poor contact between the electrostatic adsorption chuck and the conductive pad during the operation of the plasma etching device.
[0005] To achieve the above objectives, this utility model provides a conductive pad, comprising a conductive body and an insulating inner liner; the conductive body is a flexible, elongated structure with an inner cavity extending through it along its axial direction; the insulating inner liner is a flexible, elongated structure, and the insulating inner liner passes through the inner cavity of the conductive body.
[0006] Optionally, the conductor has a three-dimensional helical structure.
[0007] Optionally, the conductor is formed by spirally winding a slender sheet around an axis, the width of which is 2mm to 5mm.
[0008] Optionally, the conductor has a tubular braided structure.
[0009] Optionally, the insulating liner is made of rubber or silicone.
[0010] To achieve the above objectives, the present invention also provides a base assembly, including a conductive disk, an electrostatic adsorption chuck, and a conductive pad as described in any of the preceding claims; a mounting groove is provided on the upper surface of the conductive disk, the depth of the mounting groove being less than the natural outer diameter of the conductive pad; the conductive pad is mounted in the mounting groove; the electrostatic adsorption chuck is disposed on the upper surface of the conductive disk and presses against the conductive pad.
[0011] Optionally, the mounting groove is annular and arranged coaxially with the electrostatic adsorption chuck and the conductive disk.
[0012] Optionally, an annular mating groove is provided on the lower surface of the electrostatic adsorption chuck, the mating groove is coaxial with the electrostatic adsorption chuck, and the radius of the mating groove is the same as the radius of the mounting groove.
[0013] The sum of the depth of the mating groove and the depth of the mounting groove is less than or equal to the natural outer diameter of the conductive pad.
[0014] To achieve the above objectives, the present invention also provides a plasma etching apparatus, including a process chamber and a base assembly as described in any of the preceding claims, the base assembly being disposed within the process chamber.
[0015] Optionally, the plasma etching apparatus further includes an upper electrode, an upper electrode RF rod, and a lower electrode RF rod; the upper electrode is disposed in the process chamber and located above the base assembly, and a gap is formed between the upper electrode and the electrostatic adsorption chuck; the upper electrode RF rod is electrically connected to the upper electrode; and the lower electrode RF rod is electrically connected to the conductive disk.
[0016] Compared with the prior art, the conductive pad, base assembly, and plasma etching equipment of this invention have the following advantages:
[0017] The aforementioned conductive pad includes a conductor and an insulating inner liner. The conductor is a flexible, elongated structure with an inner cavity extending through it along its own axial direction. The insulating inner liner is also a flexible, elongated structure, and it passes through the inner cavity of the conductor. The conductive pad is applied to a base assembly of an etching apparatus. The base assembly also includes a conductive disk and an electrostatic chuck. The upper surface of the conductive disk has a mounting groove, the depth of which is less than the natural outer diameter of the conductive pad. The conductive pad is positioned in the mounting groove, and the electrostatic chuck is mounted on the upper surface of the conductive disk and presses against the conductive pad. By placing the insulating inner liner within the inner cavity of the conductor, the conductive pad mounted in the mounting groove is made flat, reducing the likelihood of partial depressions. This allows the electrostatic chuck to make uniform contact with different positions of the conductive pad, enabling power transmission and reducing or even avoiding arcing caused by uneven contact between the electrostatic chuck and the conductive pad. Attached Figure Description
[0018] The accompanying drawings are provided to better understand this utility model and do not constitute an undue limitation thereof. Wherein:
[0019] Figure 1 This is a partial structural diagram of the base assembly of an existing plasma etching device;
[0020] Figure 2 A partial structural diagram of a conductive pad in the prior art;
[0021] Figure 3 This is a schematic diagram of the structure of the conductive pad provided according to an embodiment of the present invention;
[0022] Figure 4 This is a partial structural schematic diagram of the base assembly provided according to an embodiment of the present invention;
[0023] Figure 5 This is a schematic diagram of the conductive disk of the base assembly provided according to an embodiment of the present invention;
[0024] Figure 6 This is a schematic diagram of the structure of a plasma etching apparatus provided according to an embodiment of the present invention.
[0025] [The annotations in the attached figures are explained below]:
[0026] 1. 10-Base assembly; 11. 200-Conductive disk; 12. 300-Electrostatic adsorption chuck; 13. 100-Conductive pad; 110-Conductive body; 111-Inner cavity; 120-Insulating inner liner; 14. 210-Mounting groove; 310-Matching groove; 20-Process chamber; 30-Upper electrode. Detailed Implementation
[0027] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model. Therefore, the drawings only show components related to this utility model and are not drawn according to the actual number, shape, and size of the components in implementation. In actual implementation, the type, quantity, and proportion of each component can be arbitrarily changed, and the component layout may also be more complex.
[0028] Furthermore, while each embodiment described below possesses one or more technical features, this does not imply that users of this utility model must simultaneously implement all technical features in any embodiment, or can only separately implement some or all technical features in different embodiments. In other words, provided it is feasible, those skilled in the art can selectively implement some or all technical features in any embodiment, or selectively implement a combination of some or all technical features in multiple embodiments, based on the disclosure of this utility model and depending on design specifications or implementation requirements, thereby increasing the flexibility in implementing this utility model.
[0029] As used herein, the singular forms “a,” “an,” and “the” include plural objects, and the plural form “a plurality” includes two or more objects, unless otherwise expressly indicated. As used herein, the term “or” is generally used to include the meaning of “and / or,” unless otherwise expressly indicated, and the terms “install,” “connect,” and “link” should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Connections can be mechanical or electrical. Connections can be direct or indirect through an intermediate medium, and can represent internal communication between two elements or an interaction between two elements. Relational terms such as “first,” “second,” etc., are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor do they indicate relative importance or implicitly specify the number of indicated technical features. Those skilled in the art will understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0030] Figure 1 A partial structural schematic diagram of the base assembly 1 of an existing plasma etching apparatus is shown. (See attached diagram.) Figure 1 As shown, the existing base assembly 1 includes a conductive disk 11, an electrostatic adsorption chuck 12, and a conductive pad 13. A mounting groove 14 is provided on the upper surface of the conductive disk 11, and the conductive pad 13 is mounted in the mounting groove 14. The electrostatic adsorption chuck 12 is assembled to the upper surface of the conductive disk 11 via a connector (not shown in the figure).
[0031] Ideally, the electrostatic adsorption chuck 12 and the conductive pad 13 are in uniform contact at various positions on the conductive pad 13, so that electrical energy can be transferred to the electrostatic adsorption chuck 12 through the conductive disk 11 and the conductive pad 13, thereby causing the electrostatic adsorption chuck 12 to generate electrostatic attraction to adsorb the substrate to be etched.
[0032] Figure 2 A schematic diagram of the conductive pad 13 in the prior art is shown. The conductive pad 13 is a flexible three-dimensional spiral structure formed by spirally winding thin metal wires. When this type of conductive pad 13 is installed in the mounting groove 14, it is prone to unevenness, with some parts raised and some parts recessed. This results in a larger contact area between the electrostatic chuck 12 and the raised portion of the conductive pad 13, and a smaller contact area between the electrostatic chuck 12 and the recessed portion of the conductive pad 13 when the electrostatic chuck 12 is assembled to the upper surface of the conductive disk 11. In this case, once electrical energy is applied to the conductive disk 11, the current in the larger contact area between the electrostatic chuck 12 and the conductive pad 13 becomes too large, while the current in the smaller contact area becomes too small, thus triggering an electric arc. The occurrence of an electric arc can cause abnormal alarms in the plasma etching equipment, leading to shutdown and reducing equipment productivity. Furthermore, it may also cause damage to the equipment and the substrate.
[0033] In view of this, the present invention provides a conductive pad, which aims to improve the flatness of the conductive pad in the mounting groove of the conductive disk, thereby improving the uniformity of contact between the electrostatic adsorption chuck and the conductive pad when the chuck is installed on the conductive disk, and reducing or even avoiding the generation of electric arc.
[0034] To make the objectives, advantages, and features of this utility model clearer, the following detailed description is provided in conjunction with the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to conveniently and clearly illustrate the objectives of the embodiments of this utility model. The same or similar reference numerals in the drawings represent the same or similar parts.
[0035] Figure 3 This diagram illustrates the structure of the conductive pad 100 provided in an embodiment of the present invention. Figure 3As shown, the conductive pad 100 includes a conductor 110 and an insulating inner liner 120. The conductor 110 is a flexible, elongated structure, and the conductor 110 has an inner cavity 111 extending through its own axial direction (e.g., Figure 4 (As shown). The insulating liner 120 is a flexible, elongated structure that passes through the inner cavity 111 of the conductor 110. Here, "flexible" is relative to rigidity. Both the flexible conductor 110 and the flexible insulating liner 120 are easy to bend, thereby the conductive pad 100 is easy to bend.
[0036] like Figure 4 As shown, the conductive pad 100 is used in the base assembly 10 of a plasma etching apparatus. The base assembly 10 has a structure basically similar to that of the prior art, including a conductive disk 200 and an electrostatic adsorption chuck 300. A mounting groove 210 is provided on the upper surface of the conductive disk 200. The depth of the mounting groove 210 is less than the natural outer diameter of the conductive pad 100, and the mounting groove 210 is used to mount the conductive pad 100. The electrostatic adsorption chuck 300 is assembled on the upper surface of the conductive disk 200 and presses against the conductive pad 100 mounted in the mounting groove 210.
[0037] Here, "the natural outer diameter of the conductive pad 100" refers to the outer diameter of the conductive pad 100 when it is not subjected to radial compressive force.
[0038] In the conductive pad 100 provided in this embodiment of the invention, by inserting the insulating inner liner 120 inside the inner cavity 111 of the conductor 110, when the conductive pad 100 is installed in the mounting groove 210, the insulating inner liner 120 provides a vertically downward pressure to the conductor 110, ensuring that all parts of the conductor 110 abut against the bottom of the mounting groove 210 without local bulging, thus improving the flatness of the conductive pad 100. When the electrostatic adsorption chuck 300 is assembled onto the upper surface of the conductive disk 200 and pressure-sensitive tests are performed under different assembly torques, the test results demonstrate that under different assembly torques, the electrostatic adsorption chuck 300 and different parts of the conductive pad 100 maintain uniform contact. Thus, the application of the conductive pad 100 ensures that when electrical energy is supplied to the conductive disk 200, the electrical energy can be conducted to the electrostatic adsorption chuck 300 via the conductive pad 100, preventing arcing.
[0039] The pressure-sensitive test method is as follows: A ring of pressure-sensitive test paper is attached to the electrostatic adsorption chuck 300 at the location corresponding to the mounting groove 210. Then, the electrostatic adsorption chuck 300 is assembled onto the upper surface of the conductive disk 200, and the assembly torque between the electrostatic adsorption chuck 300 and the conductive disk 200 is adjusted. After a certain period of time, the electrostatic adsorption chuck 300 is disassembled, and the pressure-sensitive test paper is observed for any indentations.
[0040] Those skilled in the art will understand that the electrostatic adsorption chuck 300 and the conductive disk 200 can be connected by a threaded connector. Therefore, by adjusting the tightness of the threaded connector, the assembly torque between the electrostatic adsorption chuck 300 and the conductive disk 200 can be adjusted.
[0041] In this embodiment of the invention, the conductor 110 can be a three-dimensional helical structure formed by a slender metal material around an axis, or it can be a tubular braided structure made of metal wires. In a preferred embodiment, the conductor 110 is a three-dimensional helical structure because the molding method of a three-dimensional helical structure is simple and the manufacturing cost is low.
[0042] More preferably, the conductor 110 is a three-dimensional spiral structure formed by a thin, elongated sheet-like structure, and the width w of the sheet-like structure is 2mm to 3mm. Compared to a conductor 110 with a three-dimensional spiral structure formed by filamentous material, the conductor 110 with a sheet-like structure provides more uniform contact between the electrostatic adsorption chuck 300 and the conductive pad 100 when in contact with the electrostatic adsorption chuck 300.
[0043] The insulating liner 120 can be made of any suitable material, including but not limited to rubber, silicone or other flexible polymer materials.
[0044] Optionally, the conductor 110 and the insulating liner 120 are first formed separately, and then the insulating liner 120 is inserted into the inner cavity 111 of the conductor 110. For ease of operation, it is preferable that the outer diameter of the insulating liner 120 is slightly smaller than the inner diameter of the conductor 110.
[0045] Furthermore, this utility model also provides a base assembly, the base assembly being... Figure 4 The base assembly 100 shown.
[0046] Usually, such as Figure 5As shown, the mounting groove 210 has a circular structure and is coaxially arranged with the electrostatic adsorption chuck 300 and the conductive disk 200. Therefore, the aforementioned "uniform contact between the electrostatic adsorption chuck 300 and different parts of the conductive pad 100" refers to the uniform contact between the electrostatic adsorption chuck 300 and the conductive pad 100 in the circumferential direction of the mounting groove 210.
[0047] Preferably, such as Figure 4 As shown, an annular mating groove 310 is also provided on the lower surface of the electrostatic adsorption chuck 300. The mating groove 310 is coaxial with the electrostatic adsorption chuck 300, and the radius of the mating groove 310 is the same as the radius of the mounting groove 210. The sum of the depth of the mating groove 310 and the depth of the mounting groove 210 is less than the natural outer diameter of the conductive pad 100. Thus, when the electrostatic adsorption chuck 300 is connected to the upper surface of the conductive disk 200, the upper end of the conductive pad 100 can be accommodated in the mating groove 310, and the electrostatic adsorption chuck 300 and the conductive disk 200 can jointly clamp the conductive pad 100.
[0048] Furthermore, such as Figure 6 As shown, the present invention also provides a plasma etching apparatus, which includes a process chamber 20 and the aforementioned base assembly 10, wherein the base assembly 10 is disposed within the process chamber 20.
[0049] Furthermore, the plasma etching apparatus also includes an upper electrode 30, an upper electrode RF rod (not shown in the figure), and a lower electrode RF rod (not shown in the figure). The upper electrode 30 is disposed within the process chamber 20 and located above the base assembly 10, with a gap formed between the upper electrode 30 and the electrostatic adsorption chuck 300. One end of the upper electrode RF rod is electrically connected to the upper electrode 30, and the other end is connected to an external RF source. One end of the lower electrode RF rod is connected to the conductive disk 200, and the other end is connected to another external RF source.
[0050] While the present invention has been disclosed above, it is not limited thereto. Those skilled in the art can make various modifications and variations to the present invention without departing from its spirit and scope. Therefore, if such modifications and variations fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include such modifications and variations.
Claims
1. A conductive pad, characterized in that, It includes a conductor and an insulating liner; the conductor is a flexible, elongated structure with an inner cavity extending through it along its axial direction; the insulating liner is a flexible, elongated structure and is disposed within the inner cavity of the conductor.
2. The conductive pad according to claim 1, characterized in that, The conductor has a three-dimensional helical structure.
3. The conductive pad according to claim 2, characterized in that, The conductor is made by spirally winding a slender sheet around an axis, the width of which is 2mm to 5mm.
4. The conductive pad according to claim 1, characterized in that, The conductor has a tubular braided structure.
5. The conductive pad according to claim 1, characterized in that, The insulating liner is made of rubber or silicone.
6. A base assembly, characterized in that, The device includes a conductive disk, an electrostatic adsorption chuck, and a conductive pad as described in any one of claims 1-5; a mounting groove is provided on the upper surface of the conductive disk, the depth of which is less than the natural outer diameter of the conductive pad; the conductive pad is mounted in the mounting groove; the electrostatic adsorption chuck is disposed on the upper surface of the conductive disk and presses against the conductive pad.
7. The base assembly according to claim 6, characterized in that, The mounting groove is annular and is arranged coaxially with the electrostatic adsorption chuck and the conductive disk.
8. The base assembly according to claim 6 or 7, characterized in that, The lower surface of the electrostatic adsorption chuck is provided with an annular mating groove, the mating groove is coaxial with the electrostatic adsorption chuck, and the radius of the mating groove is the same as the radius of the mounting groove. The sum of the depth of the mating groove and the depth of the mounting groove is less than or equal to the natural outer diameter of the conductive pad.
9. A plasma etching apparatus, characterized in that, It includes a process chamber and a base assembly as described in any one of claims 6-8, the base assembly being disposed within the process chamber.
10. The plasma etching apparatus according to claim 9, characterized in that, The plasma etching apparatus further includes an upper electrode, an upper electrode RF rod, and a lower electrode RF rod; the upper electrode is disposed in the process chamber and located above the base assembly, and a gap is formed between the upper electrode and the electrostatic adsorption chuck; the upper electrode RF rod is electrically connected to the upper electrode, and the lower electrode RF rod is electrically connected to the conductive disk.