Process chambers and semiconductor processing equipment

Abstract

A process chamber and a semiconductor process equipment are disclosed. The process chamber comprises a chamber body having an opening at a top portion thereof, an upper electrode assembly comprising an upper electrode cover plate covering the opening and an electrode assembly disposed at a bottom surface of the upper electrode cover plate, wherein an annular gap is defined between the electrode assembly and a sidewall of the chamber body, and an impedance ring assembly sleeved outside the electrode assembly, wherein the impedance ring assembly comprises dielectric rings and conductive rings which are alternately stacked, and the conductive rings are spaced apart from the electrode assembly and the sidewall of the chamber body. Each of the conductive rings is connected to at least one electrical connector. The electrical connector electrically connects the corresponding conductive ring to the chamber body in a first state, and disconnects the electrical connection between the corresponding conductive ring and the chamber body in a second state. The thickness of the impedance ring assembly can be adjusted without disassembling the upper electrode assembly, so as to adjust the distribution of the plasma current. The operation is convenient, and the production efficiency can be improved.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing equipment technology, specifically to a process chamber and semiconductor process equipment. Background Technology

[0002] Capacitively Coupled Plasma (CCP) equipment is a type of plasma generation device widely used in integrated circuit manufacturing and can be used in reactive plasma etching processes.

[0003] Figure 1 This is a schematic diagram of an existing capacitively coupled plasma (CCP) device, including a chamber body 10a, a metal substrate 20a, a contact electrode 30a, a lower electrode 40a, and an impedance ring 50a. The metal substrate 20a and the contact electrode 30a are assembled together and grounded to form an upper electrode assembly. The upper electrode assembly and the lower electrode 40a form a parallel-plate capacitor. Radio frequency (RF) power is fed to the lower electrode 40a via a matching converter using capacitive coupling. Process gas is excited between the parallel-plate capacitors to form plasma. The impedance ring 50a is arranged around the contact electrode 30a to change the specific current flow on the entire upper electrode assembly, i.e., to change the electric field distribution in the semiconductor process equipment, thereby changing the plasma distribution in the reaction chamber.

[0004] However, this scheme can only produce one type of plasma distribution. When it is necessary to adjust the plasma uniformity, it is necessary to replace the impedance ring 50a with one of different shapes or thicknesses. This not only makes the replacement operation complicated, but also affects the equipment's production capacity. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a process chamber and semiconductor process equipment, which can improve the problem of the complexity of operation and the impact on the production capacity of existing process chambers when adjusting plasma uniformity.

[0006] To address the aforementioned technical problems, in a first aspect, embodiments of this application provide a process chamber, comprising:

[0007] The chamber body has an opening at its top;

[0008] The upper electrode assembly includes an upper electrode cover plate that covers the opening, and an electrode assembly disposed on the bottom surface of the upper electrode cover plate, and an annular gap is provided between the electrode assembly and the side wall of the chamber body.

[0009] An impedance ring assembly is sleeved on the outside of the electrode assembly and located at the annular gap. The impedance ring assembly includes alternatingly stacked dielectric rings and conductive rings, with the outermost rings being dielectric rings. The conductive rings are spaced apart from the electrode assembly and the sidewalls of the chamber body.

[0010] An electrical connector is provided, wherein each conductive ring corresponds to at least one electrical connector, wherein the electrical connector electrically connects the corresponding conductive ring to the side wall of the chamber body in a first state, and disconnects the electrical connection between the corresponding conductive ring and the side wall of the chamber body in a second state.

[0011] Optionally, the electrical connector is a conductive screw;

[0012] In the first state, the conductive screw penetrates the side wall of the chamber body from the outside and is connected to the corresponding conductive ring. In the second state, the conductive screw is rotated at least to the point of separation from the corresponding conductive ring.

[0013] Optionally, the distance between the conductive ring and the electrode assembly is 0.5-10 mm; and / or,

[0014] The distance between the conductive ring and the side wall of the chamber body is 0.5-10 mm.

[0015] Optionally, two adjacent dielectric rings and conductive rings are positioned by a pin hole structure.

[0016] Optionally, the electrode assembly includes:

[0017] A flow equalizer is disposed on the bottom surface of the upper electrode cover plate;

[0018] A contact electrode is disposed on the bottom surface of the flow equalization plate, and a first annular protrusion is provided on the side of the contact electrode;

[0019] A second annular protrusion is provided on the inner side of the side wall of the chamber body. The side of the second annular protrusion facing the upper electrode cover plate is at the same height as the side of the first annular protrusion facing the upper electrode cover plate, and the distance between the second annular protrusion and the upper electrode cover plate is greater than or equal to the thickness of the impedance ring assembly.

[0020] The impedance ring assembly is sleeved on the outside of the flow equalization plate and the outside of the contact electrode, and is supported on the first annular protrusion and the second annular protrusion.

[0021] Optionally, the impedance ring assembly and the first annular protrusion are positioned by a pin hole structure.

[0022] Optionally, the side of the first annular protrusion away from the upper electrode cover is flush with the bottom surface of the contact electrode.

[0023] Optionally, a first sealing ring is provided between the impedance ring assembly and the first annular protrusion;

[0024] A second sealing ring is provided between the impedance ring assembly and the second annular protrusion.

[0025] Optionally, all of the conductive rings have the same thickness.

[0026] Secondly, embodiments of this application provide a semiconductor process apparatus, including a matching unit, a radio frequency power supply, and a process chamber as described in the above embodiments;

[0027] The chamber body is provided with a support base, and the radio frequency power supply feeds radio frequency to the support base through the matching unit.

[0028] As described above, in the process chamber of this application, the impedance ring assembly includes alternatingly stacked dielectric rings and conductive rings. Each conductive ring also corresponds to at least one electrical connector. In a first state, the electrical connector electrically connects the corresponding conductive ring to the side wall of the chamber body, and in a second state, disconnects the electrical connection between the corresponding conductive ring and the side wall of the chamber body. Therefore, in the process chamber of this embodiment, the thickness of the dielectric layer of the impedance ring assembly can be changed simply by changing the connection state of the electrical connector. This allows for adjustment of the dielectric layer thickness of the impedance ring assembly without disassembling the upper electrode assembly, thereby adjusting the distribution of plasma current. This operation is convenient and can improve production efficiency. Attached Figure Description

[0029] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of an existing capacitively coupled plasma device;

[0031] Figure 2 This is a schematic diagram of the structure of a semiconductor device provided in an embodiment of this application;

[0032] Figure 3 This is a schematic diagram of an electrical connector connected to a conductive ring according to an embodiment of this application;

[0033] Figure 4 This is a cross-sectional structural schematic diagram of a dielectric ring provided in an embodiment of this application;

[0034] Figure 5 This is a top view of a contact electrode provided in an embodiment of this application;

[0035] Figure 6 This is a schematic diagram of the assembly process of some parts of a process chamber provided in an embodiment of this application;

[0036] Figure 7 This is an equivalent circuit diagram of a capacitively coupled plasma chamber provided in an embodiment of this application;

[0037] Figure 8 This is a simulation diagram of adjusting plasma current distribution provided in an embodiment of this application.

[0038] The realization of the objectives, functional features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. The accompanying drawings have illustrated specific embodiments of this application, which will be described in more detail below. These drawings and textual descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this application to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0039] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0040] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, components, features, and elements with the same names in different embodiments of this application may have the same meaning or different meanings, the specific meaning of which must be determined by its interpretation in that specific embodiment or further in conjunction with the context of that specific embodiment.

[0041] It should be further understood that the terms "comprising" or "including" indicate the presence of the stated features, steps, operations, elements, components, items, types, and / or groups, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, types, and / or groups. The terms "or," "and / or," and "comprising at least one of the following," as used in this application, can be interpreted as inclusive, or mean any one or any combination thereof. For example, "comprising at least one of the following: A, B, C" means "any one of the following: A; B; C; A and B; A and C; B and C; A and B and C," and similarly, "A, B, or C" or "A, B, and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A and B and C." Exceptions to this definition only occur when the combination of elements, functions, steps, or operations is inherently mutually exclusive in some way.

[0042] It should be understood that although the terms first, second, third, etc., may be used in this document to describe various types of information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this document, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the singular forms “a,” “an,” and “the” used in this document are intended to also include the plural forms, unless the context indicates otherwise.

[0043] It should be understood that the terms "top", "bottom", "upper", "lower", "vertical", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application.

[0044] For ease of description, the following embodiments are all illustrated using an orthogonal space formed by a horizontal plane and a vertical direction as an example. This premise should not be construed as a limitation of this application.

[0045] Please see Figure 2 , Figure 2 This is a schematic diagram of a semiconductor device provided in an embodiment of this application. The semiconductor device may include a process chamber, a matching unit 60, and an RF power supply 70. A carrier base 13 may also be disposed within the process chamber. The carrier base 13 may be an electrostatic chuck. The RF power supply 70 feeds RF signals to the carrier base 13 through the matching unit 60 via an RF feed bar (not shown in the figure). For the working principle and process of the semiconductor process equipment in this embodiment, please refer to the following description of the process chamber in this embodiment of the invention.

[0046] The process chamber of this application may include a chamber body 10, an upper electrode assembly 20, an impedance ring assembly 30, and an electrical connector 40. The upper electrode assembly 20 may include an upper electrode cover plate 21 and an electrode assembly 22.

[0047] The top of the chamber body 10 has an opening 101; an upper electrode cover plate 21 covers the opening 101, an electrode assembly 22 is disposed on the bottom surface of the upper electrode cover plate 21, and an annular gap 102 is provided between the electrode assembly 22 and the side wall 11 of the chamber body 10; as an example, the upper electrode cover plate 21 can be connected to the opening 101 of the chamber body 10 by a snap-fit ​​method. An impedance ring assembly 30 is sleeved on the outside of the electrode assembly 22 and located at the annular gap 102. The impedance ring assembly 30 may include alternatingly stacked dielectric rings 31 and conductive rings 32, and the outermost ones are all dielectric rings 31. The conductive rings 32 are spaced apart from the electrode assembly 22 and the side wall 11 of the chamber body 10, that is, the conductive rings 32 and the electrode assembly 22 are fitted with a gap, and a gap is also provided between the conductive rings 32 and the side wall 11 of the chamber body 10. For example, the spacing between the conductive ring 32 and the electrode assembly 22, and the spacing between the conductive ring 32 and the side wall 11 of the chamber body 10, can be 0.5-10 mm, such as 0.5 mm, 1 mm, 2 mm, 3 mm, 5 mm, 7 mm, 10 mm, etc. Each conductive ring 32 also corresponds to at least one electrical connector 40. In a first state, the electrical connector 40 electrically connects the corresponding conductive ring 32 to the side wall 11 of the chamber body 10, and in a second state, disconnects the electrical connection between the corresponding conductive ring 32 and the side wall 11 of the chamber body 10.

[0048] For example, when one conductive ring 32 is provided, two dielectric rings 31 are provided, with the two dielectric rings 31 sandwiching the conductive ring 32 in the middle; when two conductive rings 32 are provided, three dielectric rings 31 are provided, where the first, third, and fifth layers are dielectric rings 31, the second and fourth layers are conductive rings 32, and so on. Each conductive ring 32 can be provided with one, two, or more electrical connectors 40. When multiple electrical connectors 40 are provided, they can be evenly distributed along the circumference of the conductive ring 32. As an example, the material of the dielectric ring 31 can be an insulating material such as quartz, and the material of the conductive ring 32 can be a conductive material such as metal.

[0049] As is common knowledge, the capacitance value of a parallel plate capacitor can be calculated using the following formula:

[0050] C=εS / d (1)

[0051] Where ε is the dielectric constant of the dielectric material, S is the relative area between the dielectric material and the electrode, and d is the thickness of the intermediate dielectric layer. According to this formula, the capacitance can be changed by altering the thickness of the intermediate dielectric layer. As mentioned above, existing technologies require replacing impedance rings of different shapes or thicknesses to adjust the plasma uniformity in the process chamber, which is cumbersome and affects equipment throughput.

[0052] In this embodiment, the process chamber, the impedance ring assembly 30, includes alternatingly stacked dielectric rings 31 and conductive rings 32. Taking an example of two conductive rings 32 (a first conductive ring 32A and a second conductive ring 32B) and three dielectric rings 31 (a first dielectric ring 31A, a second dielectric ring 31B, and a third dielectric ring 31C), the thickness of the first dielectric ring 31A is d1, the thickness of the second dielectric ring 31B is d2, and the thickness of the third dielectric ring 31C is d3. When the electrical connectors 40 corresponding to the first conductive rings 32A and 32B are both in the first state, the thickness of the dielectric layer of the impedance ring assembly 30 is d1. Based on this, the first conductive ring 32A is connected to the side... When the electrical connector 40 connected to the wall 11 is adjusted from the first state to the second state, the thickness of the dielectric layer of the impedance ring assembly 30 is d1+d2. Furthermore, when the electrical connector 40 connecting the second conductive ring 32B to the side wall 11 is adjusted from the first state to the second state, the thickness of the dielectric layer of the impedance ring assembly 30 is d1+d2+d3. Therefore, in the process chamber of this embodiment, the thickness of the dielectric layer of the impedance ring assembly 30 can be changed simply by changing the connection state of the electrical connector 40. Thus, the thickness of the dielectric layer of the impedance ring assembly 30 can be adjusted without disassembling the upper electrode assembly 20, thereby adjusting the plasma current density distribution. This is convenient to operate and can improve production efficiency.

[0053] It should be noted that the function of the electrical connector 40 is to electrically connect or de-connect the conductive ring 32 and the side wall 11 of the chamber body 10, so that the two are at the same potential or different potentials, and can switch between the two connection states. Specifically, it can be automatic or manual switching. The specific structural form of the electrical connector 40 is not particularly limited in the embodiments of this application.

[0054] As an example, please see Figure 2 and Figure 3 , Figure 3This is a schematic diagram of an electrical connector 40 connected to a conductive ring according to an embodiment of this application. The electrical connector 40 can be a conductive screw, such as a metal screw. It is understood that the diameter of the conductive screw is smaller than the thickness of the corresponding conductive ring 32. For example, when the thickness of the conductive ring 32 should be 5.4 mm, an M4 screw (3.4 mm in diameter) can be selected. In the first state, the conductive screw penetrates the side wall 11 of the chamber body 10 from the outside and connects to the corresponding conductive ring 32. It can abut against the conductive ring 32 or be further threadedly connected to the conductive ring 32 to make the conductive ring 32 and the chamber body 10 have the same potential. In the second state, the conductive screw is rotated at least until it is separated from the corresponding conductive ring 32. For example, the conductive screw can be directly removed from the side wall 11 of the chamber body 10 to disconnect the conductive ring 32 from the chamber body 10, so that the two have different potentials. Figure 3 The conductive ring 32 in the middle corresponds to six conductive screws. The number of conductive screws can be increased or decreased according to the diameter of the conductive ring 32. This application does not make any special limitation.

[0055] As an example of electrode assembly 22, please continue reading. Figure 2 The electrode assembly 22 may include a flow equalization plate 221 and a contact electrode 222. An upper electrode cover 21 seals the opening 101. For example, the upper electrode cover 21 may be directly fastened to the opening 101, or it may be hinged to the chamber body 10 to form a flip-top structure. An air inlet pipe may also be provided on the upper electrode cover 21 for introducing process gas into the process chamber. The flow equalization plate 221 is disposed on the bottom surface of the upper electrode cover 21. Multiple air equalization holes may be provided on the flow equalization plate 221, allowing the process gas to form a uniform airflow through these holes. In some embodiments, a buffer gas chamber may be formed between the flow equalization plate 221 and the upper electrode cover 21, allowing the gas to enter the buffer gas chamber and then be homogenized through the air equalization holes. The contact electrode 222 is disposed on the bottom surface of the flow equalization plate 221.

[0056] It should be noted that the above-described structures of the upper electrode cover plate 21, the flow equalization plate 221, and the contact electrode 222 are merely examples, and other conventional structures in the art can also be used. For improvements to this embodiment, please refer to the following... Figure 2 This application also provides an assembly embodiment of the impedance ring assembly 30. A first annular protrusion 231 is provided on the side of the contact electrode 222, and a second annular protrusion 12 is provided on the inner side of the sidewall 11 of the chamber body 10. The side of the second annular protrusion 12 facing the upper electrode cover plate 21 is at the same height as the side of the first annular protrusion 231 facing the upper electrode cover plate 21, and the distance between the second annular protrusion 12 and the upper electrode cover plate 21 is greater than or equal to the thickness of the impedance ring assembly 30. The impedance ring assembly 30 is sleeved on the outer side of the flow equalization plate 221 and the outer side of the contact electrode 222, and is supported on the first annular protrusion 231 and the second annular protrusion 12.

[0057] Preferably, the side of the first annular protrusion 231 furthest from the upper electrode cover plate 21 is flush with the bottom surface of the contact electrode 222, which reduces the difficulty of part processing. Generally, the thickness of the impedance ring assembly 30 should be slightly less than the thickness of the flow equalizer 221 and the contact electrode 222 (minus the thickness of the first annular protrusion 231) to ensure that assembly requirements are met. It should be noted that the thickness of each dielectric ring 31 can be the same or different. For example, if the thickness of the flow equalizer 221 and the contact electrode 222 (after subtracting the thickness of the first annular protrusion 231) is 40mm, when two conductive rings 32 and three dielectric rings 31 are provided, the thickness of the two metal rings can both be 5.4mm, totaling 10.8mm, and the thicknesses of the three dielectric rings 31 can be 10mm, 10mm, and 9.2mm respectively, or 12mm, 8mm, and 9.2mm.

[0058] In one embodiment, to improve the sealing of the process chamber, please refer to [further details]. Figure 2 A first sealing ring 51 can be provided between the impedance ring assembly 30 and the first annular protrusion 231, and a second sealing ring 52 can be provided between the impedance ring assembly 30 and the second annular protrusion 12. The groove for installing the first sealing ring 51 can be formed on the impedance ring assembly 30 or on the first annular protrusion 231. Similarly, the groove for installing the second sealing ring 52 can be formed on the impedance ring assembly 30 or on the second annular protrusion 12.

[0059] In one embodiment, to improve the assembly accuracy of the dielectric ring 31 and the conductive ring 32, please refer to... Figure 3 and Figure 4 , Figure 4 This is a cross-sectional view of a dielectric ring according to an embodiment of this application. Two adjacent dielectric rings 31 and conductive rings 32 are positioned by a pin hole structure. For example, a first pin hole 311 is provided on the dielectric ring 31, and a first pin 321 that mates with the first pin hole 311 is provided on the conductive ring 32. Alternatively, the first pin hole 311 can be located on the conductive ring 32, and the first pin 321 can be located on the dielectric ring 31.

[0060] Furthermore, the impedance ring assembly 30 and the first annular protrusion 231 of the contact electrode 222 can also be positioned using a pin hole structure, improving assembly accuracy. For example, please refer to... Figure 4 and Figure 5 , Figure 5 This is a top view of a contact electrode provided in an embodiment of this application. A second pin hole 312 is provided on the dielectric ring 31, and a second pin 232 that cooperates with the second pin hole 312 is provided on the first annular protrusion 231 of the contact electrode 222.

[0061] This application also provides assembly methods for the relevant components of the process chamber in the above embodiments. Please refer to [link to relevant documentation]. Figure 6 , Figure 6 This is a schematic diagram of the assembly process of some parts of a process chamber provided in an embodiment of this application. The specific assembly steps are as follows: First, the flow equalization plate 221 and the contact electrode 222 are assembled. The first sealing ring 51 can be pre-assembled with the first annular protrusion 231 of the contact electrode 222. Then, the pre-stacked dielectric ring 31 and conductive ring 32 (i.e., impedance ring assembly 30) are sleeved from one side of the flow equalization plate 221 on the outside of the flow equalization plate 221 and the contact electrode 222. The impedance ring assembly 30 is supported by the first annular protrusion 231 of the contact electrode 222. Next, the upper electrode cover plate 21 is assembled onto the side of the flow equalization plate 221 away from the contact electrode 222. Finally, the upper electrode cover plate 21 is vertically lowered into the chamber body 10 (the second sealing ring 52 can be pre-assembled onto the second annular protrusion 12), and the installation is completed.

[0062] The principle of adjusting plasma uniformity in the process chamber of this application is explained below. Please refer to [link / reference needed]. Figure 7 , Figure 7 This is an equivalent circuit diagram of a capacitively coupled plasma chamber provided in an embodiment of this application, wherein R feed L is the resistance of the RF feed rod. feed C is the inductance value of the RF feed rod. stray C is the capacitance to ground of the lower electrode (i.e., the bearing base 13). S For sheath capacitance, L bulk For plasma equivalent inductance, R bulk For plasma equivalent resistance, C shd-S C is the plasma sheath capacitance below contact electrode 222. shd C is the capacitance value of contact electrode 222. d-S C represents the plasma sheath capacitance value below the impedance loop assembly 30. d This is the capacitance value of the impedance loop assembly 30.

[0063] Specifically, when all electrical connectors 40 are in the first state, with the corresponding conductive rings 32 electrically connected to the sidewalls 11 of the chamber body 10, the RF power supply 70 outputs RF energy. After impedance matching by the matching unit 60, the energy is transferred to the RF feed rod, which has a resistance R. feed and inductance value L feed The RF feed rod is connected to the lower electrode, and there is a ground capacitance C between the lower electrode and the chamber body 10 (ground potential). stray After plasma is generated, a sheath capacitance C will be generated on the surface of the lower electrode. S Plasma can be equivalent to a resistor R. bulk and inductor Lbulk In series, the plasma will generate capacitance C on the lower surface of the contact electrode 222 and the lower surface of the impedance ring assembly 30, respectively. shd-S and C d-S The contact electrode 222 itself and the flow equalizer 221 (ground potential) also have a capacitance C. shd In the impedance ring assembly 30, there will also be a capacitance C between all the dielectric rings 31 and the conductive rings 32 (ground potential). d . Figure 7 The area inside the dashed box is the equivalent circuit diagram of the impedance loop assembly 30 and the upper electrode assembly 20. It can be seen from the diagram that changing C of the impedance loop assembly 30... d The size of the current can be adjusted to regulate the ratio of current flowing through the plasma, through the contact electrode 222, and through the dielectric ring 31, thereby regulating the plasma uniformity.

[0064] Please combine Figure 2 The following example illustrates the method for adjusting plasma homogeneity, using two conductive rings 32 (first conductive ring 32A and second conductive ring 32B) and three dielectric rings 31 (first dielectric ring 31A, second dielectric ring 31B, and third dielectric ring 31C). The thickness of the first dielectric ring 31A is d1, the thickness of the second dielectric ring 31B is d2, and the thickness of the third dielectric ring 31C is d3. The contact area between the dielectric rings 31 and the conductive rings 32 is assumed to be the same, S, and the dielectric constant of the dielectric rings 31 is ε.

[0065] When the first conductive ring 32A and the second conductive ring 32B are grounded (connected to the side wall 11 of the chamber body 10) through the first conductive screw 40A and the second conductive screw 40B respectively, the capacitance C of the impedance ring assembly 30 d The structure is a parallel capacitor, with the two terminals being the lower surface of the first dielectric ring 31A (plasma potential) and the lower surface of the first conductive ring 32A (ground potential). The formula for calculating the capacitance of the impedance ring assembly 30 is as follows:

[0066] C d1 =εS / d1 (2)

[0067] When you need to deal with C dDuring adjustment, the first conductive screw 40A connecting the first conductive ring 32A to the side wall 11 can be removed. The first conductive ring 32A no longer has a ground potential, and the structure with a ground potential is the second conductive ring 32B. The two equivalent electrodes of this parallel capacitor are the lower surface of the first dielectric ring 31A and the lower surface of the second conductive ring 32B, respectively. At this time, the distance between the two electrodes becomes d1 + d2. This is because the conductive ring 32 is made of a conductive material, so its thickness can be ignored when calculating the capacitance value. Therefore, it is preferable that all conductive rings 32 have the same thickness to increase the versatility of components. Of course, the thickness of the conductive rings 32 can be different to achieve precise adjustment of the plasma distribution in the vertical direction. The capacitance calculation formula for the impedance ring assembly 30 at this time is:

[0068] C d2 =εS / (d1+d2) (3)

[0069] Similarly, after removing the second conductive screw 40B connecting the second conductive ring 32B to the side wall 11, the capacitance value of the dielectric ring is:

[0070] C d3 =εS / (d1+d2+d3) (4)

[0071] The capacitance of the impedance ring assembly 30 can be adjusted by controlling whether the electrical connector 40 electrically connects the conductive ring 32 to the side wall 11, thereby adjusting the uniformity of the plasma.

[0072] Simulations were performed with a base 13 diameter of 200 mm, two metal rings each 5.4 mm thick, and three dielectric rings 31 with thicknesses of 10 mm, 10 mm, and 9.2 mm, respectively. The capacitance values ​​of the impedance ring assembly 30 were C... d1 C d2 and C d3 At that time, the change in plasma current distribution on the surface of the lower electrode (i.e., the support base 13) is as follows: Figure 8 As shown in Table 1, the plasma current uniformity increases with the capacitance value of the impedance loop assembly 30 from C... d1 Change to C d3 Along the radial direction of the support base 13, the uniformity of the plasma current is improved.

[0073] Table 1. Plasma current uniformity of impedance loop assembly under different capacitance values

[0074] Impedance loop component capacitance value Plasma current uniformity <![CDATA[C d1 ]]> 11.2％ <![CDATA[C d2 ]]> 8％ <![CDATA[C d3 ]]> 4.7％

[0075] The foregoing has provided a detailed description of a process chamber and semiconductor process equipment provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. It should be noted that the descriptions of each embodiment in this application have different emphases; parts not described in detail in a particular embodiment can be referred to in the relevant descriptions of other embodiments.

[0076] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. The technical features of the technical solution of this application can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are also included within the patent protection scope of this application, as long as the combination of these technical features does not contradict each other.

Claims

1. A process chamber, characterized in that, include: The chamber body has an opening at its top; The upper electrode assembly includes an upper electrode cover plate that covers the opening, and an electrode assembly disposed on the bottom surface of the upper electrode cover plate, wherein an annular gap is provided between the electrode assembly and the side wall of the chamber body. An impedance ring assembly is sleeved on the outside of the electrode assembly and located at the annular gap. The impedance ring assembly includes alternatingly stacked dielectric rings and conductive rings, with the outermost rings being dielectric rings. The conductive rings are spaced apart from the electrode assembly and the sidewalls of the chamber body. An electrical connector is provided, wherein each conductive ring corresponds to at least one electrical connector, wherein the electrical connector electrically connects the corresponding conductive ring to the side wall of the chamber body in a first state, and disconnects the electrical connection between the corresponding conductive ring and the side wall of the chamber body in a second state.

2. The process chamber according to claim 1, characterized in that, The electrical connector is a conductive screw; In the first state, the conductive screw penetrates the side wall of the chamber body from the outside and is connected to the corresponding conductive ring. In the second state, the conductive screw is rotated at least to the point of separation from the corresponding conductive ring.

3. The process chamber according to claim 1, characterized in that, The distance between the conductive ring and the electrode assembly is 0.5-10 mm; and / or, The distance between the conductive ring and the side wall of the chamber body is 0.5-10 mm.

4. The process chamber according to claim 1, characterized in that, The two adjacent dielectric rings and the conductive rings are positioned by a pin hole structure.

5. The process chamber according to claim 1, characterized in that, The electrode assembly includes: A flow equalizer is disposed on the bottom surface of the upper electrode cover plate; A contact electrode is disposed on the bottom surface of the flow equalization plate, and a first annular protrusion is provided on the side of the contact electrode; A second annular protrusion is provided on the inner side of the side wall of the chamber body. The side of the second annular protrusion facing the upper electrode cover plate is at the same height as the side of the first annular protrusion facing the upper electrode cover plate, and the distance between the second annular protrusion and the upper electrode cover plate is greater than or equal to the thickness of the impedance ring assembly. The impedance ring assembly is sleeved on the outside of the flow equalization plate and the outside of the contact electrode, and is supported on the first annular protrusion and the second annular protrusion.

6. The process chamber according to claim 5, characterized in that, The impedance ring assembly and the first annular protrusion are positioned by a pin hole structure.

7. The process chamber according to claim 5, characterized in that, The side of the first annular protrusion away from the upper electrode cover plate is flush with the bottom surface of the contact electrode.

8. The process chamber according to claim 5, characterized in that, A first sealing ring is provided between the impedance ring assembly and the first annular protrusion. A second sealing ring is provided between the impedance ring assembly and the second annular protrusion.

9. The process chamber according to any one of claims 1-8, characterized in that, All of the conductive rings have the same thickness.

10. A semiconductor process apparatus, characterized in that, Includes a matching unit, an RF power supply, and the process chamber as described in any one of claims 1-9; The chamber body is provided with a support base, and the radio frequency power supply feeds radio frequency to the support base through the matching unit.

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