Process chamber and semiconductor process equipment

Abstract

The invention discloses a process chamber and semiconductor process equipment, and the process chamber comprises a chamber body which is provided with an opening at the top; the upper electrode assembly comprises an upper electrode cover plate covering the opening and an electrode assembly arranged on the bottom surface of the upper electrode cover plate, and an annular gap is formed between the electrode assembly and the side wall of the chamber body; the impedance ring assembly is arranged on the outer side of the electrode assembly in a sleeving mode, the impedance ring assembly comprises dielectric rings and conducting rings which are alternately arranged in a stacked mode, and the conducting rings, the electrode assembly and the side wall of the cavity body are arranged at intervals; each conducting ring corresponds to at least one electric connecting piece, the corresponding conducting ring is electrically connected with the chamber body through the electric connecting piece in a first state, and the electric connection between the corresponding conducting ring and the chamber body is disconnected in a second state. According to the invention, the thickness of the impedance ring assembly can be adjusted without dismounting the upper electrode assembly so as to adjust the distribution of plasma current, the operation is convenient, and the production efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor manufacturing equipment, and in particular to a process chamber and semiconductor process equipment. Background Art

[0002] Capacitively coupled plasma (CCP) equipment is one of the plasma generating devices, which is widely used in the manufacture of integrated circuits and can be used for reactive plasma etching processes.

[0003] Figure 1 The present invention is a schematic diagram of the structure of an existing capacitively coupled plasma 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. The radio frequency power RF is fed to the lower electrode 40a in a capacitive coupling manner through a matcher, and the 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 direction of the current on the entire upper electrode assembly, that is, to change the distribution of the electric field in the semiconductor process equipment, so as to achieve the purpose of changing the distribution of the plasma in the reaction chamber.

[0004] However, this solution can only produce one form of plasma distribution. When the plasma uniformity needs to be adjusted, the impedance ring 50a of different shapes or thicknesses needs to be replaced, which not only makes the replacement operation complicated, but also affects the production capacity of the equipment. Summary of the invention

[0005] In view of the above technical problems, the present application provides a process chamber and semiconductor process equipment, which can improve the problem that the existing process chamber has complex operation when adjusting plasma uniformity, which affects the production capacity of the equipment.

[0006] In order to solve the above technical problems, in a first aspect, an embodiment of the present application provides a process chamber, comprising:

[0007] a chamber body having an opening at the top;

[0008] An upper electrode assembly, comprising an upper electrode cover plate covering the opening, and an electrode assembly disposed on the bottom surface of the upper electrode cover plate, wherein an annular gap is disposed 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 dielectric rings and conductive rings that are alternately stacked, and the dielectric rings are located on the outermost side. The conductive rings are spaced from the electrode assembly and the side wall of the chamber body.

[0010] An electrical connector, each of the conductive rings corresponds to at least one electrical connector, and 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 at least rotated to be separated 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 via a pin hole structure.

[0016] Optionally, the electrode assembly includes:

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

[0018] A contact electrode is arranged on the bottom surface of the current equalizer plate, and a first annular protrusion is arranged on the side surface of the contact electrode;

[0019] A second annular protrusion is provided on the inner side of the side wall of the chamber body, a side of the second annular protrusion facing the upper electrode cover plate and a side of the first annular protrusion facing the upper electrode cover plate are located at the same height, and a 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 outer side of the current equalizer plate and the outer side 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 via a pin hole structure.

[0022] Optionally, a surface of the first annular protrusion away from the upper electrode cover plate is flush with a 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 arranged between the impedance ring assembly and the second annular protrusion.

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

[0026] In a second aspect, an embodiment of the present application provides a semiconductor process equipment, including a matcher, a radio frequency power supply, and a process chamber as described in the above embodiments;

[0027] A supporting base is arranged in the chamber body, and the radio frequency power source feeds radio frequency to the supporting base through the matching device.

[0028] As described above, in the process chamber of the present application, the impedance ring assembly includes dielectric rings and conductive rings that are alternately stacked, and each conductive ring also corresponds to at least one electrical connector. 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. Therefore, in the process chamber of this embodiment, the thickness of the dielectric layer of the impedance ring assembly can be changed by only changing the connection state of the electrical connector, so that the thickness of the dielectric layer of the impedance ring assembly can be adjusted without disassembling the upper electrode assembly to achieve the adjustment of the distribution of the plasma current. The operation is convenient and the production efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.

[0030] Figure 1 It is a structural schematic diagram of an existing capacitively coupled plasma device;

[0031] Figure 2 is a structural schematic diagram of a semiconductor device provided in an embodiment of the present application;

[0032] Figure 3 It is a structural schematic diagram of an electrical connector and a conductive ring provided in an embodiment of the present application;

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

[0034] Figure 5 is a schematic diagram of a top view structure of a contact electrode provided in an embodiment of the present application;

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

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

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

[0038] The realization of the purpose, functional features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. The above-mentioned drawings have shown clear embodiments of this application, which will be described in more detail later. These drawings and textual descriptions are not intended to limit the scope of the concept of this application in any way, but to illustrate the concept of this application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0039] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0040] It should be noted that, in this article, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element. In addition, components, features, and elements with the same name in different embodiments of the present application may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context of the specific embodiment.

[0041] It should be further understood that the terms "comprising" and "including" indicate the presence of the described features, steps, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms "or", "and / or", "including at least one of the following", etc. used in this application may be interpreted as inclusive, or mean any one or any combination. For example, "including 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 for another example, "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 will 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 herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of this document, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, as used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless otherwise indicated in the context.

[0043] It should be understood that the orientations or positional relationships indicated by terms such as "top", "bottom", "up", "down", "vertical", and "horizontal" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0044] For ease of description, in the following embodiments, the orthogonal space formed by the horizontal plane and the vertical direction is used as an example for explanation, and this premise should not be understood as a limitation to the present application.

[0045] See also Figure 2 , Figure 2 1 is a schematic diagram of the structure of a semiconductor device provided in an embodiment of the present application. The semiconductor device may include a process chamber, a matcher 60 and a radio frequency power supply 70. A support base 13 may be provided in the process chamber. The support base 13 may be an electrostatic chuck. The radio frequency power supply 70 feeds radio frequency to the support base 13 through a radio frequency feeding rod (not shown) via the matcher 60. For the working principle and process of the semiconductor process device in this embodiment, please refer to the description of the process chamber in the embodiment of the present invention below.

[0046] The process chamber of the present 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 is provided with an opening 101; the upper electrode cover plate 21 is sealed at the opening 101, the electrode assembly 22 is arranged on the bottom surface of the upper electrode cover plate 21, and an annular gap 102 is arranged 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 snapping. The impedance ring assembly 30 is sleeved on the outside of the electrode assembly 22 and is located at the annular gap 102. The impedance ring assembly 30 can include dielectric rings 31 and conductive rings 32 that are alternately stacked, and the dielectric rings 31 are located at the outermost side, and the conductive rings 32 and the electrode assembly 22 and the side wall 11 of the chamber body 10 are all arranged at intervals, that is, the conductive rings 32 and the electrode assembly 22 are assembled with a gap, and a gap is also arranged 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 may 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, which electrically connects the corresponding conductive ring 32 to the side wall 11 of the chamber body 10 in a first state, and disconnects the electrical connection between the corresponding conductive ring 32 and the side wall 11 of the chamber body 10 in a second state.

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

[0049] As common knowledge, the capacitance calculation method of a flat plate capacitor is based on the following formula:

[0050] C=εS / d (1)

[0051] Among them, 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 dielectric layer in the middle. According to this formula, the capacitance can be changed by changing the thickness of the dielectric layer in the middle. As mentioned above, when the plasma uniformity in the process chamber needs to be adjusted in the prior art, it is necessary to replace the impedance ring of different shapes or thicknesses to change the capacitance, which is cumbersome and affects the equipment production capacity.

[0052] In the process chamber of the present embodiment, the impedance ring assembly 30 includes dielectric rings 31 and conductive rings 32 alternately stacked. For example, two conductive rings 32 are provided (respectively, a first conductive ring 32A and a second conductive ring 32B) and three dielectric rings 31 are provided (respectively, 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 ring 32A and the second conductive ring 32B are both in the first state, the thickness of the dielectric layer of the impedance ring assembly 30 is d1. On this basis, the first conductive ring 32A and the side conductive ring 32B are connected to each other. 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. Further, 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 by only changing the connection state of the electrical connector 40. Therefore, the thickness of the dielectric layer of the impedance ring assembly 30 can be adjusted without disassembling the upper electrode assembly 20 to achieve the adjustment of the plasma current density distribution. The operation is convenient and the production efficiency can be improved.

[0053] It should be noted that the function of the electrical connector 40 is to electrically connect or disconnect the conductive ring 32 and the side wall 11 of the chamber body 10, so that the two can achieve the same potential or different potentials, and can switch between the two connection states. It can be switched automatically or manually. The specific structural form of the electrical connector 40 is not particularly limited in the embodiment of the present application.

[0054] As an example, see Figure 2 and Figure 3 , Figure 3It is a structural schematic diagram of an electrical connector and a conductive ring provided in an embodiment of the present application. The electrical connector 40 can be a conductive screw, such as a metal screw. It can be 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 (diameter 3.4 mm) can be selected. In the first state, the conductive screw passes through the side wall 11 of the chamber body 10 from the outside and is connected to the corresponding conductive ring 32. It can abut against the conductive ring 32, or it can be further threaded with 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 at least rotated to separate 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 to achieve unequal potentials between the two. Figure 3 The conductive ring 32 corresponds to six conductive screws, and the number of the conductive screws can be increased or decreased according to the diameter of the conductive ring 32, and this application does not make any special limitation.

[0055] As an example of an electrode assembly 22, please continue to refer to Figure 2 , the electrode assembly 22 may include a flow equalizer 221 and a contact electrode 222. The upper electrode cover plate 21 is sealed at the opening 101. For example, the upper electrode cover plate 21 may be directly fastened to the opening 101, or it may be hinged to the chamber body 10 to form a flip cover structure. An air inlet pipe may also be provided on the upper electrode cover plate 21 to introduce process gas into the process chamber. The flow equalizer 221 is provided on the bottom surface of the upper electrode cover plate 21. A plurality of gas equalizer holes may be provided on the flow equalizer 221. The process gas may form a uniform airflow through the gas equalizer holes. In some embodiments, a buffer air cavity may be formed between the flow equalizer 221 and the upper electrode cover plate 21. The gas enters the buffer air cavity and then passes through the gas equalizer holes for uniformization. The contact electrode 222 is provided on the bottom surface of the flow equalizer 221.

[0056] It should be noted that the above structures of the upper electrode cover plate 21, the current equalizer plate 221 and the contact electrode 222 are only examples, and other conventional structures in the art may also be used. Figure 2 The present application also provides an assembly embodiment of an impedance ring assembly 30. A first annular protrusion 231 is also provided on the side of the contact electrode 222, and a second annular protrusion 12 is provided on the inner side of the side wall 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 current equalizing 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 away from the upper electrode cover plate 21 is flush with the bottom surface of the contact electrode 222, which can reduce the difficulty of part processing. In general, the thickness of the impedance ring assembly 30 should be slightly smaller than the thickness of the flow plate 221 and the contact electrode 222 (minus the thickness of the first annular protrusion 231) to ensure that the assembly requirements are met. It should be noted that the thickness of each dielectric ring 31 can be the same or different. For example, the thickness of the flow plate 221 and the contact electrode 222 (minus 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 be 5.4mm each, a total of 10.8mm, and the thickness 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 continue to refer to Figure 2 A first sealing ring 51 may be provided between the impedance ring assembly 30 and the first annular protrusion 231, and a second sealing ring 52 may be provided between the impedance ring assembly 30 and the second annular protrusion 12. The groove for installing the first sealing ring 51 may 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 may be formed on the impedance ring assembly 30 or on the second annular protrusion 12.

[0059] In one embodiment, in order to improve the assembly accuracy of the dielectric ring 31 and the conductive ring 32, refer to Figure 3 and Figure 4 , Figure 4 : is a schematic diagram of a cross-sectional structure of a dielectric ring provided in an embodiment of the present application, wherein 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 matching the first pin hole 311 is provided on the conductive ring 32. Of course, the first pin hole 311 may be provided on the conductive ring 32, and the first pin 321 may be provided on the dielectric ring 31.

[0060] In addition, the impedance ring assembly 30 and the first annular protrusion 231 of the contact electrode 222 can also be positioned by a pin hole structure to improve assembly accuracy. Figure 4 and Figure 5 , Figure 5 It is a schematic diagram of a top view of a contact electrode provided in an embodiment of the present application. A second pin hole 312 is provided on the dielectric ring 31 , and a second pin 232 matching with the second pin hole 312 is provided on the first annular protrusion 231 of the contact electrode 222 .

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

[0062] The principle of adjusting plasma uniformity in the process chamber of the present application is described below. Figure 7 , Figure 7 is an equivalent circuit diagram of a capacitively coupled plasma chamber provided in an embodiment of the present application, wherein R feed is the resistance of the RF feed rod, L feed is the inductance of the RF feed rod, C stray is the capacitance of the lower electrode (i.e. the supporting base 13) to the ground, C S is the sheath capacitance, L bulk is the plasma equivalent inductance, R bulk is the plasma equivalent resistance, C shd-S is the plasma sheath capacitance below the contact electrode 222, C shd is the capacitance value of the contact electrode 222, C d-S is the plasma sheath capacitance value below the impedance ring assembly 30, C d is the capacitance value of the impedance loop component 30 .

[0063] Specifically, when all the electrical connectors 40 are in the first state and the corresponding conductive rings 32 are electrically connected to the side wall 11 of the chamber body 10, the RF power supply 70 outputs RF energy, and after impedance matching by the matcher 60, the energy is transmitted to the RF feeding 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 capacitance C between the lower electrode and the chamber body 10 (ground potential) stray After the plasma is generated, a sheath capacitance C is generated on the surface of the lower electrode. S , plasma can be equivalent to a resistor R bulk and inductor Lbulk The plasma will generate capacitance C on the lower surface of the contact electrode 222 and the lower surface of the impedance ring component 30 respectively. shd-S and C d-S There is also a capacitance C between the contact electrode 222 itself and the current equalizer 221 (ground potential). shd There will also be capacitance C between all dielectric rings 31 and conductive rings 32 (ground potential) in the impedance ring assembly 30. d . Figure 7 The equivalent circuit diagram of the impedance ring assembly 30 and the upper electrode assembly 20 is shown in the dotted line frame. It can be seen from the figure that changing the C of the impedance ring assembly 30 d The size of can adjust the ratio of the current passing through the plasma, flowing through the contact electrode 222 and flowing through the dielectric ring 31, thereby adjusting the plasma uniformity.

[0064] Please combine Figure 2 , the following continues to take the example of setting two conductive rings 32 (respectively the first conductive ring 32A and the second conductive ring 32B) and setting three dielectric rings 31 (respectively the first dielectric ring 31A, the second dielectric ring 31B, and the third dielectric ring 31C) to explain the method of adjusting plasma uniformity. Among them, 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 areas of the dielectric ring 31 and the conductive ring 32 are assumed to be the same, both S, and the dielectric constant of the dielectric ring 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 It is a parallel capacitor structure, and the two electrodes of the capacitor are the lower surface of the first dielectric ring 31A (plasma potential) and the lower surface of the first conductive ring 32A (ground potential). At this time, the calculation formula of the capacitance value of the impedance ring assembly 30 is:

[0066] C d1 =εS / d1 (2)

[0067] When to C dWhen making adjustments, the first conductive screw 40A connecting the first conductive ring 32A to the side wall 11 can be removed, and the first conductive ring 32A no longer has a ground potential. At this time, 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. At this time, the distance between the two electrodes becomes d1+d2. This is because the conductive ring 32 is made of conductive material, so the thickness can be ignored when calculating the capacitance value. Therefore, it is preferred that the thickness of all conductive rings 32 is equal to increase the versatility of components. Of course, the thickness of the conductive ring 32 can be different to achieve precise adjustment of the plasma distribution in the vertical direction. The capacitance calculation formula of 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 is 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] The simulation is performed with the diameter of the supporting base 13 being 200 mm, the thickness of the two metal rings being 5.4 mm, and the thickness of the three dielectric rings 31 being 10 mm, 10 mm, and 9.2 mm respectively. When the capacitance values ​​of the impedance ring assembly 30 are C d1 , C d2 and C d3 When , the plasma current distribution on the surface of the lower electrode (i.e., the supporting base 13) changes as follows Figure 8 As shown in Table 1, the plasma current uniformity is shown in Table 1. It can be seen that as the capacitance value of the impedance ring component 30 increases from C d1 Change to C d3 , along the radial direction of the supporting base 13, the uniformity of the plasma current is improved.

[0073] Table 1. Plasma current uniformity under different capacitance values ​​of impedance ring components

[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 above is a detailed introduction to a process chamber and semiconductor process equipment provided by the present application. This article uses specific examples to illustrate the principles and implementation methods of the present application. It should be noted that in the present application, the descriptions of various embodiments have different focuses. For parts that are not described or recorded in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0076] The above are only preferred embodiments of the present application, and the patent scope of the present application is not limited thereto. The various technical features of the technical solution of the present application can be arbitrarily combined. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. Any equivalent structure or equivalent process transformation made using the contents of the specification and drawings of this application, or directly or indirectly used in other related technical fields, as long as there is no contradiction in the combination of these technical features, are equally included in the patent protection scope of the present application.

Claims

1. A process chamber, characterized in that: include: a chamber body having an opening at the top; An upper electrode assembly, comprising an upper electrode cover plate covering the opening, and an electrode assembly disposed on the bottom surface of the upper electrode cover plate, wherein an annular gap is disposed 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 dielectric rings and conductive rings that are alternately stacked, and the dielectric rings are located on the outermost side. The conductive rings are spaced from the electrode assembly and the side wall of the chamber body. An electrical connector, each of the conductive rings corresponds to at least one electrical connector, and 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 connection piece 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 at least rotated to be separated 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: Two adjacent dielectric rings and conductive rings are positioned by a pin hole structure.

5. The process chamber according to claim 1, characterized in that: The electrode assembly comprises: A flow equalizer plate, arranged on the bottom surface of the upper electrode cover plate; A contact electrode is arranged on the bottom surface of the current equalizer plate, and a first annular protrusion is arranged on the side surface of the contact electrode; A second annular protrusion is provided on the inner side of the side wall of the chamber body, a side of the second annular protrusion facing the upper electrode cover plate and a side of the first annular protrusion facing the upper electrode cover plate are located at the same height, and a 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 outer side of the current equalizer plate and the outer side 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 via a pin hole structure.

7. The process chamber according to claim 5, characterized in that: A surface 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 arranged between the impedance ring assembly and the second annular protrusion.

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

10. A semiconductor process equipment, characterized in that: Comprising a matcher, a radio frequency power supply, and a process chamber according to any one of claims 1 to 9; A supporting base is arranged in the chamber body, and the radio frequency power source feeds radio frequency to the supporting base through the matching device.

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