Semiconductor processing apparatus

Abstract

The application provides a semiconductor process equipment, which comprises a process chamber, an upper radio frequency source, a radio frequency coil structure and a coil grounding device, wherein the process chamber comprises a process cavity and a dielectric cavity, the dielectric cavity is located above the process cavity, and the dielectric cavity is sealingly connected with the process cavity; the inner diameter of the dielectric cavity increases from top to bottom; the radio frequency coil structure comprises a three-dimensional helical coil, the three-dimensional helical coil surrounds the dielectric cavity, the inner diameter of the three-dimensional helical coil increases from top to bottom, and both ends of the three-dimensional helical coil are electrically connected with the upper radio frequency source; the coil grounding device is electrically connected with the three-dimensional helical coil in a position-adjustable mode, the three-dimensional helical coil is grounded through the coil grounding device, and the grounding position is located between the two ends of the three-dimensional helical coil. The semiconductor process equipment provided by the application can improve the uniformity of plasma distribution.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and more specifically, to a semiconductor process apparatus. Background Technology

[0002] Deep silicon etching has important applications in integrated circuits (ICs), microelectromechanical systems (MEMS), and advanced packaging, and is a crucial process in industrial production. Since traditional wet etching is isotropic, only anisotropic dry etching can achieve deep silicon etching. Low-temperature plasma technology is a fundamental aspect of dry etching. Among these, inductively coupled plasma (ICP) and capacitively coupled plasma (CCP) are commonly used plasma sources for dry etching and thin film deposition in the semiconductor field. ICP sources generate plasma by using a high-frequency electromagnetic field produced by a high-frequency current passing through a coil to excite gas. Because they can operate at relatively low chamber pressures and offer high plasma density and minimal damage to the workpiece, they are typically used in deep silicon etching where high plasma density is required.

[0003] With the development of the semiconductor industry, improving etching process performance on large-volume chambers and large-size wafers is an important method to reduce production costs. However, the larger the chamber size, the higher the requirements for plasma distribution uniformity. Therefore, how to improve the plasma distribution uniformity of large-size chambers is a major challenge in the semiconductor field, such as deep silicon etching and high-density plasma chemical vapor deposition (HDPCVD). Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes a semiconductor process apparatus that can improve the uniformity of plasma distribution, thereby meeting the requirements of process uniformity for large-size chambers.

[0005] To achieve the objectives of this invention, a semiconductor process apparatus is provided, comprising a process chamber, an upper radio frequency (RF) source, an RF coil structure, and a coil grounding device. The process chamber includes a process cavity and a dielectric cavity, the dielectric cavity being located above the process cavity and sealed to it. The inner diameter of the dielectric cavity increases from top to bottom. The RF coil structure includes a three-dimensional spiral coil, which surrounds the dielectric cavity, and its inner diameter increases from top to bottom. Both ends of the three-dimensional spiral coil are electrically connected to the upper RF source.

[0006] The coil grounding device is electrically connected to the three-dimensional spiral coil in an adjustable position, and the three-dimensional spiral coil is grounded through the coil grounding device, with the grounding position located between the two ends of the three-dimensional spiral coil.

[0007] Optionally, the coil grounding device includes a grounding component and a conductive fixing component. The conductive fixing component is connected to the three-dimensional spiral coil in an adjustable position, and the conductive fixing component is electrically connected to the three-dimensional spiral coil.

[0008] The conductive fixing member is provided with a first mating part, and the grounding member is provided with a second mating part, and the first mating part and the second mating part are detachably electrically connected.

[0009] Optionally, one of the first mating part and the second mating part is a slot, and the other of the first mating part and the second mating part is a plug-in, wherein the plug-in is inserted into the slot.

[0010] Optionally, the conductive fixing member is slidably connected to the three-dimensional spiral coil along the spiral direction of the three-dimensional spiral coil, and the conductive fixing member is provided with a fastening structure for fixing the conductive fixing member to the three-dimensional spiral coil when the conductive fixing member slides to a preset grounding position.

[0011] Optionally, the coil grounding device further includes a slide rail, which is fixed above the dielectric cavity and spaced apart on the side of the three-dimensional spiral coil away from the dielectric cavity; the slide rail is provided with a groove, which extends along a designated path, and the grounding member slides in cooperation with the groove. The designated path is configured to allow the grounding member to slide along the groove to a position corresponding to the conductive fixing member, so that the second mating part can be connected to the first mating part.

[0012] Optionally, the designated path extends along the helical direction of the three-dimensional helical coil; or, it extends radially along the three-dimensional helical coil and at an angle relative to the horizontal plane.

[0013] Optionally, the coil grounding device includes multiple grounding components and multiple conductive fixing components. The multiple conductive fixing components are connected to different positions of the three-dimensional spiral coil, and each grounding component is electrically connected to the corresponding conductive fixing component, so that the three-dimensional spiral coil is grounded at different positions simultaneously.

[0014] Optionally, there are two three-dimensional spiral coils, with each turn of the two three-dimensional spiral coils arranged side by side in the horizontal direction in a one-to-one correspondence, and the two three-dimensional spiral coils are symmetrical with respect to the axial direction of the dielectric cavity, and the current directions are the same; both ends of each three-dimensional spiral coil are electrically connected to the upper radio frequency source.

[0015] The connection position of one of the three-dimensional spiral coils to the corresponding coil grounding device is symmetrical with respect to the axial direction of the dielectric cavity as is the connection position of the other three-dimensional spiral coil to the corresponding coil grounding device, so that the two three-dimensional spiral coils are grounded at positions symmetrical with respect to the axial direction of the dielectric cavity.

[0016] Optionally, the coil grounding device corresponding to each of the three-dimensional spiral coils includes a grounding component and a conductive fixing component. The conductive fixing component is connected to the three-dimensional spiral coil and is electrically connected to the three-dimensional spiral coil. The conductive fixing component is provided with a first mating part, and the grounding component is provided with a second mating part. The first mating part and the second mating part are detachably electrically connected.

[0017] The two three-dimensional spiral coils each have multiple conductive fasteners of the same number. The different conductive fasteners on each three-dimensional spiral coil are located at different positions between the two ends of the three-dimensional spiral coil. The positions of the conductive fasteners on one three-dimensional spiral coil and the positions of the conductive fasteners on the other three-dimensional spiral coil are symmetrical with respect to the axial direction of the medium cavity.

[0018] The grounding element on each of the three-dimensional spiral coils is selectively connected to any one of the plurality of conductive fixing elements, and the conductive fixing element connected to the grounding element on one of the three-dimensional spiral coils is symmetrical with respect to the axial direction of the dielectric cavity to the conductive fixing element connected to the grounding element on the other three-dimensional spiral coil.

[0019] Optionally, the upper radio frequency source includes two radio frequency power supplies and two matching transformers; one end of the three-dimensional spiral coil is connected to one of the radio frequency power supplies through one of the matching transformers, and the other end of the three-dimensional spiral coil is electrically connected to the other radio frequency power supply through the other matching transformer; or,

[0020] The upper radio frequency source includes a radio frequency power supply and a matching unit, and both ends of the three-dimensional spiral coil are electrically connected to the radio frequency power supply through the matching unit.

[0021] Optionally, an adjustable capacitor is provided on the circuit between each end of the three-dimensional spiral coil and the matching device connected thereto.

[0022] Optionally, the upper radio frequency source includes a radio frequency power supply and a matching unit, and both ends of the three-dimensional spiral coil are electrically connected to the radio frequency power supply through the matching unit;

[0023] The two ends of the three-dimensional spiral coil and the coil segment between the grounding member adjacent to the two ends are respectively the first coil segment and the second coil segment;

[0024] Wherein, the first coil segment is electrically connected to the matching unit via a cable, and the absolute value of the difference between the sum of the lengths of the first coil segment and the cable and the length of the second coil segment is equal to half the wavelength of the radio frequency signal output by the radio frequency power supply; or,

[0025] The second coil segment is electrically connected to the matching unit via the cable, and the difference between the sum of the lengths of the second coil segment and the cable and the length of the first coil segment is equal to half the wavelength of the radio frequency signal output by the radio frequency power supply.

[0026] Optionally, the upper radio frequency source includes two radio frequency power supplies and two matching circuits;

[0027] One end of the three-dimensional spiral coil is connected to one of the radio frequency power supplies through one of the matching devices, and the other end of the three-dimensional spiral coil is electrically connected to another radio frequency power supply through another matching device;

[0028] The phase difference between the radio frequency signals output by the two radio frequency power supplies is equal to half the period of the radio frequency signal.

[0029] The present invention has the following beneficial effects:

[0030] The semiconductor process equipment provided by this invention has two ends of a three-dimensional spiral coil that are both electrically connected to an upper radio frequency source as radio frequency feed terminals. The coil grounding device is electrically connected to the three-dimensional spiral coil in an adjustable position, and the three-dimensional spiral coil is grounded through the coil grounding device. The grounding position is located between the two ends of the three-dimensional spiral coil. Since the position of the coil grounding device is adjustable, the electrical conduction position as the radio frequency feed terminal is adjustable. By adjusting the electrical conduction position, the plasma distribution can be adjusted, thereby increasing the means of adjusting the uniformity of plasma distribution and improving the flexibility of process adjustment. This can improve the uniformity of plasma distribution to meet the process uniformity requirements of large-size chambers. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of a semiconductor process equipment provided in this embodiment;

[0032] Figure 2 for Figure 1 Partial structural diagram of semiconductor process equipment;

[0033] Figure 3 This is another schematic diagram of the semiconductor process equipment provided in this embodiment;

[0034] Figure 4 for Figure 1 A schematic diagram of the orthographic projection of the radio frequency coil structure onto the radial section;

[0035] Figure 5 A comparison diagram of plasma distribution curves corresponding to different regions of the radio frequency coil structure;

[0036] Figure 6 This is another structural schematic diagram of the semiconductor process equipment provided in this embodiment;

[0037] Figure 7 for Figure 6 A schematic diagram of the orthographic projection of the radio frequency coil structure onto the radial section;

[0038] Figure 8 This is a schematic diagram of the radio frequency feed-in and feed-out principle of one of the three-dimensional spiral coils;

[0039] Figure 9 A comparison of plasma distribution curves corresponding to different electrical conduction positions;

[0040] Figure 10 This is a schematic diagram of the conductive fixing component and grounding component used in this embodiment;

[0041] Figure 11 This is a schematic diagram of the guide rail and grounding component used in this embodiment;

[0042] Figure 12 This is a diagram showing the positional relationship between the coil grounding device and the three-dimensional spiral coil used in this embodiment;

[0043] Figure 13 A schematic diagram of the orthographic projection of a single three-dimensional helical coil onto a radial section;

[0044] Figure 14 This is an equivalent circuit diagram of the radio frequency coil structure used in this embodiment;

[0045] Figure 15 for Figure 14 The equivalent circuit diagram of one of the three-dimensional spiral coils;

[0046] Figure 16 This is another equivalent circuit diagram of the radio frequency coil structure used in this embodiment;

[0047] Figure 17 This is another equivalent circuit diagram of the radio frequency coil structure used in this embodiment. Detailed Implementation

[0048] To enable those skilled in the art to better understand the technical solutions of the present invention, the semiconductor process equipment provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0049] Please refer to the following: Figure 1 and Figure 2 The semiconductor process equipment provided in this embodiment includes a process chamber, a radio frequency coil structure 5, and an upper radio frequency source (not shown in the figure). The process chamber includes a dielectric cavity 1 and a process cavity 2. The dielectric cavity 1 is made of ceramic or quartz, for example, to feed the radio frequency energy provided by the radio frequency coil structure 5 into the interior of the process chamber. The dielectric cavity 1 is located above the process cavity 2 and is sealed to the process cavity 2. In some embodiments, the dielectric cavity 1 and the process cavity 2 can be integrally formed, or they can be fixedly connected by a detachable method such as fasteners. In addition, optionally, a Faraday shield can be provided between the dielectric cavity 1 and the radio frequency coil structure 5, for example.

[0050] Furthermore, an air inlet is provided at the top of the media cavity 1, which is connected to the air intake device 4. The air intake device 4 can introduce process gas into the process space 3 in the process chamber through the air inlet. In some embodiments, the air inlet may be located at the center of the top of the media cavity 1.

[0051] Alternatively, the inner diameter of the process cavity 2 may be the same at different positions in the vertical direction, and the maximum inner diameter of the medium cavity 1 may be the same as the inner diameter of the process cavity 2.

[0052] The semiconductor process equipment provided in this embodiment also includes a base 7 disposed in the process chamber 2 for supporting the wafer 8, and a lower radio frequency source (not shown in the figure) electrically connected to the base 7. The lower radio frequency source includes, for example, a matching circuit and a bias power supply, for outputting lower electrode power to the base 7. The base 7 is, for example, an electrostatic chuck or a mechanical chuck. In addition, an exhaust device (not shown in the figure) is provided at the bottom of the process chamber 2 to exhaust waste gas from the process chamber 2.

[0053] In some optional embodiments, a gas equalization device 9 is provided within the process space 3 formed by the aforementioned medium cavity 1 and process cavity 2, near the connection between the medium cavity 1 and process cavity 2, to improve the uniformity of plasma distribution. The gas equalization device 9 is, for example, a flow equalization plate or a flow rectifier.

[0054] In some optional embodiments, the volume of the process space 3 formed by the dielectric cavity 1 and the process cavity 2 is greater than or equal to 109L, for example, it can be applied to the etching process of a 12-inch wafer. Of course, the embodiments of the present invention are not limited to this. In practical applications, the volume of the process space 3 can also be set to any other arbitrary value to meet the process requirements of wafers of different sizes, such as 6-inch wafers, 8-inch wafers, etc.

[0055] Under a certain chamber pressure (i.e., vacuum), the alternating electromagnetic field generated by the RF coil provides energy to the gas molecules within the chamber. The gas molecules closest to the RF coil ionize first, and then the energy gradually transfers downwards within the chamber, achieving uniform ignition throughout the entire chamber. However, in existing technologies, dielectric components such as dielectric cylinders or dielectric windows are typically used to feed the RF energy from the RF coil into the interior of the dielectric cavity. The internal space formed by these dielectric components and the process cavity has the same vertical inner diameter. In this case, especially for large-volume chambers and large-size wafers, lower chamber pressure and upper electrode power can hinder the transfer of RF energy within the chamber. Only the gas molecules near the coil ionize, failing to "ignite" the entire chamber; this phenomenon is called quenching. Although plasma initiation can be achieved by increasing the chamber pressure and the upper electrode power, in order to meet the process requirements for uniformity and etching morphology, specifically, using a lower chamber pressure can improve the mean free path and uniformity of the plasma, while using a lower upper electrode power can reduce etching damage and improve the surface roughness of the etching morphology. Therefore, achieving plasma initiation under the conditions of low chamber pressure and low upper electrode power is an urgent problem to be solved.

[0056] To address the aforementioned issues, the semiconductor process apparatus provided in this embodiment of the invention features a dielectric cavity 1 with an inner diameter that increases from top to bottom. The radio frequency coil structure 5 includes a three-dimensional spiral coil that surrounds the dielectric cavity 1, with its inner diameter increasing from top to bottom. Because the inner diameter of the dielectric cavity 1 near the inlet is smaller, the energy provided to the gas molecules within the cavity by the alternating electromagnetic field generated by the radio frequency coil structure 5 is sufficient to ionize most of the gas molecules passing through the plane containing this inner diameter. Furthermore, since the inner diameter of the dielectric cavity 1 increases from top to bottom, the energy for ionizing the gas can be smoothly transferred downwards within the cavity, avoiding energy transfer obstruction due to excessively large cavity space. This allows for plasma ignition even under low cavity pressure and low upper electrode power conditions, thereby improving the mean free path and uniformity of the plasma, reducing etching damage, and improving the surface roughness of the etched morphology. Furthermore, by increasing the inner diameter of the dielectric cavity 1 from top to bottom, the volume of the cavity can be increased to the size required by the process. For example, for wafers with a diameter of 8 inches or 12 inches, the maximum inner diameter of the dielectric cavity can be increased to 200 mm or 300 mm or more, thus making it compatible with large-size wafers.

[0057] It should be noted that by increasing the inner diameter of the three-dimensional spiral coil from top to bottom, the distance between the three-dimensional spiral coil and the dielectric cavity 1 at different positions in the vertical direction is not too large. This ensures that the energy provided by the three-dimensional spiral coil at different inner diameters can be fed into the enclosed space 3 through the dielectric cavity 1. In some optional embodiments, the distance between the three-dimensional spiral coil and the dielectric cavity 1 at different positions in the vertical direction is the same, which helps to improve the uniformity of plasma distribution.

[0058] The structure of the aforementioned medium cavity 1 can be varied, for example, as follows: Figure 2 As shown, the orthographic projection of the medium cavity 1 on its axial section is an arch shape, thus achieving an increase in the inner diameter of the medium cavity 1 from top to bottom. However, the embodiments of the present invention are not limited to this; in practical applications, the medium cavity can also adopt other structures, for example, as... Figure 3 As shown, the medium cavity 1' includes a plurality of cylindrical sub-cavities arranged sequentially along its axial direction. Figure 3 Five cylindrical sub-cavities (1a, 1b, 1c, 1d, 1e) are shown, forming a stepped cavity structure. For example, each of the five cylindrical sub-cavities includes an annular top cover and an annular sidewall. The upper end of the annular sidewall of each cylindrical sub-cavity is connected to the outer edge of the annular top cover, and the lower end of the annular sidewall of each cylindrical sub-cavity is connected to the inner edge of the annular top cover of the cylindrical sub-cavity below and adjacent to it. The uppermost cylindrical sub-cavity includes a flat top cover and an annular sidewall, which is connected to the inner edge of the annular top cover of the cylindrical sub-cavity below and adjacent to it. An air inlet is provided in the flat top cover, which is connected to an air intake device 4, which can introduce process gas into the enclosed space 3 through the air inlet. In some embodiments, the air inlet is optionally located at the top center of the medium cavity 1'.

[0059] Furthermore, the inner diameters of the multiple cylindrical sub-cavities increase from top to bottom. For example, as... Figure 3As shown, the inner diameters of the annular sidewalls of the five cylindrical sub-cavities (1a, 1b, 1c, 1d, 1e) increase sequentially from top to bottom. In the RF coil structure 5, the inner diameter of the three-dimensional spiral coil increases from top to bottom. Because the inner diameter of the dielectric cavity 1 near the air inlet is relatively small, the energy provided to the gas molecules in the cavity by the alternating electromagnetic field generated by the RF coil structure 5 can ionize most of the gas molecules passing through the plane of that inner diameter. At the same time, since the inner diameter of the dielectric cavity 1' increases from top to bottom, the energy for ionizing the gas can be smoothly transferred to the lower part of the cavity, avoiding energy transfer obstruction due to excessive cavity space. Thus, even under low cavity pressure and low upper electrode power conditions, plasma ignition can be achieved, thereby improving the mean free path and uniformity of the plasma, and also reducing etching damage and improving the surface roughness of the etched morphology. Furthermore, by increasing the inner diameter of the dielectric cavity 1 from top to bottom, the volume of the cavity can be increased to the size required by the process. For example, for wafers with a diameter of 8 inches or 12 inches, the maximum inner diameter of the dielectric cavity can be increased to 200 mm or 300 mm or more, thus making it compatible with large-size wafers. Optionally, multiple cylindrical sub-cavities can be integrally formed.

[0060] In this embodiment, with Figure 2 Taking the medium cavity 1 shown as an example, as Figure 4 As shown, the RF coil structure 5 includes two three-dimensional spiral coils (5a, 5b). The turns of each coil in the two three-dimensional spiral coils (5a, 5b) are arranged side-by-side in a horizontal direction, corresponding one-to-one. The two three-dimensional spiral coils (5a, 5b) are symmetrical about the axial direction of the dielectric cavity 1, and the current directions are the same. For example... Figure 4 The current in both of the two three-dimensional spiral coils (5a, 5b) shown flows clockwise. By making the two three-dimensional spiral coils (5a, 5b) axially symmetrical with respect to the dielectric cavity 1, the non-uniform plasma distribution caused by the structural asymmetry of a single three-dimensional spiral coil can be compensated, thereby improving the uniformity of plasma distribution.

[0061] In some alternative embodiments, the two three-dimensional helical coils (5a, 5b) can be fixed by a support structure disposed outside the dielectric cavity 1. This support structure, for example, consists of multiple annular support plates, each supporting one turn of the three-dimensional helical coil. Alternatively, the above-mentioned support structure may not be provided, and the two three-dimensional helical coils (5a, 5b) can be fixed to the outside of the dielectric cavity 1 solely by the gravity of the two three-dimensional helical coils (5a, 5b).

[0062] In some embodiments, the first end 51a and the second end 52a of the three-dimensional spiral coil 5a are respectively connected to the upper radio frequency source and ground; the first end 51b and the second end 52b of the three-dimensional spiral coil 5b are also respectively connected to the upper radio frequency source and ground, that is, one end of each three-dimensional spiral coil is a radio frequency feed-in end and the other end is a radio frequency feed-out end. However, in this case, the means of adjusting the plasma distribution uniformity are limited, for example, by adjusting the magnitude of the radio frequency power applied to each spiral segment in different regions of the corresponding cavity of the three-dimensional spiral coil to adjust the plasma distribution uniformity. For example, the same three-dimensional spiral coil is divided into two spiral segments in the axial direction (i.e., vertical direction) of the dielectric cavity 1, and the two spiral segments are connected in parallel, that is, each of the two spiral segments has a radio frequency feed-in end and is electrically connected to the upper radio frequency source, and each of the two spiral segments has a radio frequency feed-out end and is grounded. Moreover, one of the two spiral segments corresponding to the central region of the dielectric cavity 1 is the first spiral segment, and the other corresponding to the edge region of the dielectric cavity 1 is the second spiral segment, such as Figure 5 As shown, curve A is the plasma distribution curve generated by applying the first radio frequency power to the first helical segment (the horizontal direction represents the position in the radial direction of the chamber, and the vertical direction represents the plasma density); curve B is the plasma distribution curve generated by applying the second radio frequency power to the second helical segment; curve C is the plasma distribution curve formed by combining curves A and B. When the magnitudes of the first and second radio frequency powers are adjusted, curves A and B will change along the curves with the magnitude of the radio frequency power. Figure 5 The plasma is moved in the Y direction to adjust the uniformity of plasma distribution.

[0063] The inventors discovered that adjusting the radio frequency power alone can only make curves A and B move along... Figure 5 The plasma can only move in the Y direction and cannot move radially (perpendicular to the Y direction) within the cavity. Therefore, the means to adjust the uniformity of plasma distribution are limited, and the adjustment effect of plasma distribution uniformity is poor. In particular, it cannot meet the requirements of plasma distribution uniformity for applications with large volume cavities and large-size wafers.

[0064] To further improve the uniformity of plasma distribution, the semiconductor process equipment provided in this embodiment of the invention, based on the aforementioned dielectric cavity, also incorporates the following improvements: Figure 6 As shown, the first end 51a and the second end 52a of the three-dimensional spiral coil 5a are both electrically connected to the upper radio frequency source; the first end 51b and the second end 52b of the three-dimensional spiral coil 5b are also electrically connected to the upper radio frequency source, that is, both ends of each three-dimensional spiral coil are radio frequency feed-in ends.

[0065] Based on this, the semiconductor process equipment provided in this embodiment of the invention further includes a coil grounding device. This coil grounding device is electrically connected to a three-dimensional spiral coil, and the three-dimensional spiral coil is grounded through the coil grounding device, with the grounding position located between the two ends of the three-dimensional spiral coil. Since the position of the coil grounding device is adjustable, the electrical conduction position, as the RF feed end, is also adjustable. By adjusting this electrical conduction position, the plasma distribution can be adjusted, thereby increasing the means of adjusting plasma distribution uniformity and improving the flexibility of process adjustment. This, in turn, improves plasma distribution uniformity to meet the process uniformity requirements of large-size chambers.

[0066] In some alternative embodiments, the above-described coil grounding device includes a grounding element and a conductive fixing element. For example... Figure 6 and Figure 7 As shown, taking two three-dimensional spiral coils (5a, 5b) as an example, spiral coil 5a has a grounding component 6a and a conductive fixing component 7a, and spiral coil 5b has a grounding component 6b and a conductive fixing component 7a. The conductive fixing component 7a is adjustable and connected to spiral coil 5a, for example, at the electrically conductive position Fa, and is electrically connected to spiral coil 5a. The conductive fixing component 7b is adjustable and connected to spiral coil 5b, for example, at the electrically conductive position Fb, and is electrically connected to spiral coil 5b. Figure 7 As shown, the electrical conduction position Fa of the grounding element 6a and the three-dimensional spiral coil 5a is located between the two ends (51a, 52a) of the three-dimensional spiral coil 5a at intervals, that is, the electrical conduction position Fa does not coincide with the two ends (51a, 52a). Similarly, the electrical conduction position Fb of the grounding element 6b and the three-dimensional spiral coil 5b is located between the two ends (51b, 52b) of the three-dimensional spiral coil 5b at intervals, that is, the electrical conduction position Fb does not coincide with the two ends (51a, 52a).

[0067] Furthermore, each of the aforementioned conductive fasteners 7a and 7b is provided with a first mating portion, and each of the grounding members 6a and 6b is provided with a second mating portion. The first mating portion and the second mating portion are detachably electrically connected and electrically conductive to each other. In this way, the grounding member can be fixed to the three-dimensional spiral coil by the conductive fasteners and electrically conductive to it. Moreover, since the first mating portion and the second mating portion are detachably electrically connected, the installation and removal of the grounding member and the conductive fasteners can be realized. This allows for selective connection of the grounding member to any one of the multiple conductive fasteners on the same three-dimensional spiral coil, or it allows for the replacement of the grounding member.

[0068] There are various ways in which the first mating part and the second mating part can be detachably connected. In some optional embodiments, one of the first mating part and the second mating part is a slot, and the other of the first mating part and the second mating part is a plug-in, which is inserted into the slot. For example, as Figure 10 As shown, each of grounding components 6a and 6b includes a connecting rod 61 and a connector 62 and a handle 63 respectively disposed at its two ends. Each of conductive fixing components 7a and 7b is provided with a slot 71 and limiting members 72 disposed on two opposite side walls of the slot 71. Both the connector 62 and the limiting members 72 are elastic members. When the grounding component needs to be inserted into the conductive fixing component, the connector 62, as it passes through the gap between the two limiting members 72, interacts with the limiting members 72 to generate elastic deformation, allowing the connector 62 to be inserted into the slot 71. After insertion, the connector 62 and the limiting members 72 return to their original shape, at which point they cooperate to confine the connector 62 within the slot 71. Similarly, when the grounding component needs to be removed from the conductive fixing component, the connector 62 and the limiting members 72 interact to generate elastic deformation, allowing the connector 62 to move out of the slot 71 through the gap between the two limiting members 72.

[0069] There are various ways to adjust the electrical conduction position. In some optional embodiments, for example, the conductive fixing member is connected to the three-dimensional spiral coil in an adjustable position. Since the position of the conductive fixing member is adjustable, it can change the position of the grounding member 6a on the three-dimensional spiral coil 5a, which can be any position on the three-dimensional spiral coil 5a between its two ends (51a, 52a); and change the position of the grounding member 6b on the three-dimensional spiral coil 5b, which can be any position on the three-dimensional spiral coil 5b between its two ends (51b, 52b).

[0070] For example, each of the two three-dimensional spiral coils has multiple corresponding conductive fasteners, and the number is the same, for example, one or two for each. Different conductive fasteners on each three-dimensional spiral coil are located at different positions between the two ends of the coil. To ensure that the current direction is the same at all positions on the two three-dimensional spiral coils (5a, 5b), the positions of the conductive fasteners on one three-dimensional spiral coil are symmetrical with respect to the axial direction of the dielectric cavity, corresponding one-to-one with the positions of the conductive fasteners on the other three-dimensional spiral coil. Each three-dimensional spiral coil can have at least one grounding element, which can be selectively connected to any one of the multiple conductive fasteners on the same three-dimensional spiral coil to adjust the electrical conduction position. After selecting one of the different conductive fasteners, the grounding element can be manually connected to the selected conductive fastener. Similarly, the grounding element can be manually replaced between different conductive fasteners.

[0071] In some optional embodiments, to ensure that the current direction is the same at each position on the two three-dimensional spiral coils (5a, 5b), the electrical conduction positions (i.e., the connected conductive fixings) of each grounding component corresponding to one of the three-dimensional spiral coils are symmetrical with respect to the axial direction of the dielectric cavity 1 in a one-to-one correspondence with the electrical conduction positions (i.e., the connected conductive fixings) of each grounding component corresponding to the other three-dimensional spiral coil. For example, as... Figure 7 As shown, the three-dimensional spiral coil 5a corresponds to a grounding element 6a, and the three-dimensional spiral coil 5b corresponds to a grounding element 6b. Furthermore, the conduction positions Fa and Fb are symmetrical with respect to the axial direction of the dielectric cavity 1. For example, as... Figure 12 As shown, taking a three-dimensional spiral coil 5a with three conductive fixing members as an example, the three members are located at three designated electrical conduction positions (Fa1 to Fa3) arranged in a row along the radial direction of the three-dimensional spiral coil 5a. In this case, the grounding member 6a can be selectively connected to the conductive fixing member corresponding to any one of the three electrical conduction positions (Fa1 to Fa3). Similarly, a three-dimensional spiral coil 5b has three conductive fixing members, which are located at three designated electrical conduction positions (Fb1 to Fb3) arranged in a row along the radial direction of the three-dimensional spiral coil 5b. The grounding member 6b can be selectively connected to the conductive fixing member corresponding to any one of the three electrical conduction positions (Fb1 to Fb3). To ensure that the current direction is the same at all positions on the two three-dimensional spiral coils (5a, 5b), when grounding component 6a is connected to the conductive fixing component corresponding to the conductive position Fa1, grounding component 6b is connected to the conductive fixing component corresponding to the conductive position Fb1; when grounding component 6a is connected to the conductive fixing component corresponding to the conductive position Fa2, grounding component 6b is connected to the conductive fixing component corresponding to the conductive position Fb2; and when grounding component 6a is connected to the conductive fixing component corresponding to the conductive position Fa3, grounding component 6b is connected to the conductive fixing component corresponding to the conductive position Fb3. Of course, in practical applications, the conductive positions of the grounding components corresponding to the two three-dimensional spiral coils (5a, 5b) can be asymmetrical depending on different requirements.

[0072] The following example, using a three-dimensional spiral coil 5a with a grounding component 6a, will explain in detail the principle of adjusting the plasma distribution uniformity by adjusting the electrical conduction position Fa. Specifically, as... Figure 8As shown, the first end 51a and the second end 52a of the three-dimensional spiral coil 5a are both connected to the upper RF source as RF feed terminals, while the grounding component 6a and the electrically conductive position Fa of the three-dimensional spiral coil 5a are grounded through the grounding component 6a as RF feed terminals. In this case, the current directions in the two coil segments of the three-dimensional spiral coil 5a located on both sides of the electrically conductive position Fa are opposite. If the RF power fed into the two ends (51a, 52a) of the three-dimensional spiral coil 5a is the same, then if the electrically conductive position Fa is closer to the first end 51a at the center of the cavity, the impedance on the coil segment (closer to the center of the cavity) between the electrically conductive position Fa and the first end 51a is less than the impedance on the coil segment (closer to the edge of the cavity) between the electrically conductive position Fa and the second end 52a. Therefore, the RF power allocated to the coil segment (closer to the center of the cavity) between the electrically conductive position Fa and the first end 51a is greater than the RF power allocated to the coil segment (closer to the edge of the cavity) between the electrically conductive position Fa and the second end 52a. Figure 9 As shown, curve A1 is the plasma distribution curve generated by the coil segment of the three-dimensional helical coil 5a near the center of the chamber (the horizontal direction represents the radial position of the chamber, and the vertical direction represents the plasma density); curve B1 is the plasma distribution curve generated by the coil segment of the three-dimensional helical coil 5a near the edge of the chamber; curve C1 is the plasma distribution curve formed by combining curves A1 and B1. The plasma distribution shown by curve C1 indicates that the plasma density in the corresponding central region of the chamber is significantly higher than that in the corresponding edge region, indicating poor plasma distribution uniformity.

[0073] In this case, the plasma distribution uniformity can be improved by changing the electrical conduction position Fa. For example, if the electrical conduction position Fa is adjusted to a new electrical conduction position away from the first end 51a of the chamber center, such as... Figure 9As shown, curve A2 is the plasma distribution curve generated by the coil segment of the three-dimensional spiral coil 5a near the center of the chamber after adjustment (the horizontal direction represents the radial position of the chamber, and the vertical direction represents the plasma density); curve B2 is the plasma distribution curve generated by the coil segment of the three-dimensional spiral coil 5a near the edge of the chamber after adjustment; and curve C2 is the plasma distribution curve formed by combining curves A2 and B2. The plasma distribution shown by curve C2 indicates that the difference between the plasma density in the corresponding central region of the chamber and the plasma density in the corresponding edge region is significantly reduced after adjustment, thereby improving the uniformity of plasma distribution. Furthermore, comparing curve A1 before adjustment with curve A2 after adjustment, and comparing curve B1 before adjustment with curve B2 after adjustment, it can be seen that by adjusting the electrical conduction position, both curves A1 and B1 can be expanded along the X direction. This movement cannot be achieved by adjusting the RF power level as described above. Therefore, by adjusting the electrical conduction position, an additional means of adjusting plasma distribution uniformity is added, thereby improving the flexibility of process adjustment and ultimately improving plasma distribution uniformity to meet the process uniformity requirements of large-size chambers.

[0074] It should be noted that in practical applications, the same three-dimensional spiral coil can also be equipped with multiple grounding devices, and different grounding devices are located at different electrical conduction positions; that is, the electrical conduction positions of the grounding devices and the three-dimensional spiral coil do not coincide. Furthermore, it should be noted that when the same three-dimensional spiral coil is equipped with two grounding devices, the coil segment between the two grounding devices is short-circuited and therefore has no current flowing through it. Similarly, when the same three-dimensional spiral coil is equipped with three or more grounding devices, only the two ends of the three-dimensional spiral coil and the two coil segments between the two adjacent grounding devices have current flowing through them. All other coil segments between these two grounding devices are short-circuited and therefore have no current flowing through them. Therefore, the same three-dimensional spiral coil should ideally be equipped with a maximum of two grounding devices.

[0075] To facilitate adjustment of the electrical conduction position, in some alternative embodiments, the aforementioned conductive fixing member is slidably connected to the three-dimensional spiral coil along the spiral direction of the three-dimensional spiral coil, and the conductive fixing member is provided with a fastening structure for fixing the conductive fixing member to the three-dimensional spiral coil when the conductive fixing member slides to a preset grounding position. Specifically, as shown... Figure 13 As shown, taking a three-dimensional spiral coil as an example, the conductive fixing member and the three-dimensional spiral coil are along the spiral direction of the three-dimensional spiral coil (e.g., Figure 13 The conductive fixing member is slidably connected in the G direction, allowing it to slide to any position on the three-dimensional helical coil between its two ends (51, 52). The conductive fixing member is provided with a fastening structure for securing it to the corresponding electrically conductive position (e.g., ...). Figure 13 When the conductive fixing member is in position F), it is fixedly connected to the three-dimensional spiral coil. The above-mentioned fastening structure can have various different structures, such as a damper or a fastener. When the conductive fixing member slides to the designated position and is fixed to the three-dimensional spiral coil, the grounding member is then connected to the conductive fixing member. The designated position is the electrical conduction position. Alternatively, the grounding member can be connected to the conductive fixing member first, and then the conductive fixing member can be driven to slide together with the grounding member. This embodiment of the invention does not have any particular limitations on this. Furthermore, the sliding of the conductive fixing member can be manually driven or automatically driven using a motor, cylinder, or other driving device.

[0076] It should also be noted that in practical applications, the aforementioned conductive fixing component may be omitted, and the grounding component may be directly slidably connected to the three-dimensional spiral coil. This embodiment of the invention does not impose any particular restrictions on this.

[0077] like Figure 6 and Figure 11 As shown, corresponding to each three-dimensional spiral coil, the coil grounding device also includes a slide rail. Taking two three-dimensional spiral coils (5a, 5b) as an example, three-dimensional spiral coil 5a corresponds to one slide rail 8a, and three-dimensional spiral coil 5b corresponds to one slide rail 8b. Each of the slide rails 8a and 8b is fixed above the dielectric cavity 1 and is located at intervals on the side of the three-dimensional spiral coil away from the dielectric cavity 1, that is, the slide rail does not contact the three-dimensional spiral coil. The slide rail can be fixed above the dielectric cavity 1 by a fixing bracket; as shown Figure 11 As shown, each of slide rails 8a and 8b is provided with a groove 81, which extends along a specified path. The grounding member slides in conjunction with the groove 81, for example, as... Figure 6 As shown, the connecting rod 61 of the grounding component passes through the groove 81 and can move along... Figure 6 The grounding member slides along the D direction, which is the specified path mentioned above. This specified path is configured to allow the grounding member to slide along the slide groove 81 to a position corresponding to the conductive fixing member, so that the second mating part can connect with the first mating part. For example, the specified path extends radially along the three-dimensional spiral coil and is inclined relative to the horizontal plane, so that the grounding member can move to the position of any one of the multiple turns of coils with different radii.

[0078] In some optional embodiments, the coil grounding device includes multiple grounding elements and multiple conductive fixing elements. The multiple conductive fixing elements are adjustablely connected to different positions of the three-dimensional helical coil. Each grounding element is electrically connected to a corresponding conductive fixing element, so that the three-dimensional helical coil is grounded simultaneously at different positions. For example, as... Figure 12As shown, the turns of the two three-dimensional spiral coils (5a, 5b) are arranged side by side in the horizontal direction, corresponding to each other. The two three-dimensional spiral coils (5a, 5b) are symmetrical with respect to the axial direction of the dielectric cavity 1, and the current directions are the same. Both ends of each three-dimensional spiral coil are electrically connected to the upper radio frequency source. Furthermore, the connection position of one three-dimensional spiral coil 5a to the corresponding coil grounding device is symmetrical with respect to the axial direction of the dielectric cavity 1 as the connection position of the other three-dimensional spiral coil 5b to the corresponding coil grounding device, so that the two three-dimensional spiral coils (5a, 5b) are grounded at positions symmetrical with respect to the axial direction of the dielectric cavity 1. Specifically, taking a three-dimensional spiral coil 5a with three conductive fixing members as an example, the three members are located at three designated electrical conduction positions (Fa1 to Fa3) arranged in a row along the radial direction of the three-dimensional spiral coil 5a. The designated path of the slide groove 81 on the slide rail 8a extends along the arrangement direction of the three electrical conduction positions (Fa1 to Fa3). In this case, the grounding member 6a can selectively slide along the slide groove 81 to the position corresponding to any one of the three electrical conduction positions (Fa1 to Fa3) and connect with the corresponding conductive fixing member. Similarly, three conductive fixing members are provided on the three-dimensional spiral coil 5b, which are located at three designated electrical conduction positions (Fb1 to Fb3) arranged in a row along the radial direction of the three-dimensional spiral coil 5b. The designated path of the slide groove 81 on the slide rail 8b extends along the arrangement direction of the three electrical conduction positions (Fb1 to Fb3). In this case, the grounding member 6b can selectively slide along the slide groove 81 to the position corresponding to any one of the three electrical conduction positions (Fb1 to Fb3) and connect with the corresponding conductive fixing member.

[0079] In some optional embodiments, to ensure that the current direction is the same at all positions on the two three-dimensional spiral coils (5a, 5b), the number of grounding elements corresponding to the two three-dimensional spiral coils (5a, 5b) is the same, for example, one for each, or two for each. Furthermore, the electrical conduction positions of the grounding elements corresponding to one three-dimensional spiral coil are symmetrical with respect to the axial direction of the dielectric cavity 1 in a one-to-one correspondence with the electrical conduction positions of the grounding elements corresponding to the other three-dimensional spiral coil. For example, as... Figure 12As shown, the three-dimensional spiral coil 5a corresponds to a grounding element 6a, and the three-dimensional spiral coil 5b corresponds to a grounding element 6b. Furthermore, the three electrical conduction positions (Fa1~Fa3) and the three electrical conduction positions (Fb1~Fb3) are symmetrically positioned relative to the axis of the dielectric cavity 1. In use, the electrical conduction position of the grounding element 6a should be symmetrical to the electrical conduction position of the grounding element 6b relative to the axis of the dielectric cavity 1. That is, if the grounding element 6a is located at electrical conduction position Fa1, then the grounding element 6b is located at electrical conduction position Fb1; if the grounding element 6a is located at electrical conduction position Fa2, then the grounding element 6b is located at electrical conduction position Fb2; if the grounding element 6a is located at electrical conduction position Fa3, then the grounding element 6b is located at electrical conduction position Fb3.

[0080] Preferably, to ensure equal spacing between different positions of the slide rail and the three-dimensional spiral coil, the slide rail and the dielectric cavity 1 have similar shapes, such as an arc shape. Using the aforementioned slide rail, the grounding component can be moved along the groove 81 on the slide rail to the corresponding position. Then, by moving the grounding component closer to the conductive fixing component (i.e., in the E direction), it can be connected to the corresponding conductive fixing component, thereby improving the convenience of adjusting the electrical conduction position. In practical applications, the grounding component can be manually slid along the D direction and moved along the E direction, or it can be automatically driven to slide along the D direction and move along the E direction using a motor, cylinder, or other driving device.

[0081] It should be noted that the specified path is not limited to the direction D described above. In practical applications, the specified path can also be any other direction, which is set so that each grounding component can slide along the groove to the position corresponding to any conductive fixing component, thereby adjusting the electrical conduction position. For example, the specified path can also extend along the helical direction of the three-dimensional spiral coil. In this case, the grounding component can slide to any position on the three-dimensional spiral coil between its two ends.

[0082] It should also be noted that the number of three-dimensional helical coils is not limited to two. In practical applications, a single three-dimensional helical coil can also be used, for example... Figure 13 The middle part is shown.

[0083] In some alternative embodiments, such as Figure 14 As shown, the upper RF source includes an RF power supply 9 and a matching unit 10. Both ends of each three-dimensional spiral coil are electrically connected to the RF power supply 9 through the matching unit 10. Taking two three-dimensional spiral coils (5a, 5b) as an example, by making the first ends (51a, 51b) and the second ends (52a, 52b) of the two three-dimensional spiral coils (5a, 5b) electrically connected to the same upper RF source, that is, the two three-dimensional spiral coils share one upper RF source, which can reduce the configuration of the upper RF source and reduce costs.

[0084] Based on this, such as Figure 14 and Figure 15 As shown, in the two three-dimensional spiral coils (5a, 5b), the three-dimensional spiral coil 5a is equivalent to an inductor L1. The coil segments between the two ends of the three-dimensional spiral coil 5a and the grounding components 6a adjacent to the two ends are respectively the first coil segment and the second coil segment, which are equivalent to the first sub-inductor L1. 11 Second sub-inductor L 12 Moreover, the second coil segment (i.e., the second sub-inductor L) 12 Relative to the first coil segment (i.e., the first sub-inductor L) 11 () Closer to the center of the dielectric cavity 1. Specifically, the three-dimensional spiral coil 5a corresponds to a grounding element 6a, which must be adjacent to both ends of the three-dimensional spiral coil 5a. However, if there are two grounding elements 6a, such as Figure 16 As shown, one grounding component 6a is adjacent to one end of the three-dimensional spiral coil 5a, and the other grounding component 6a is adjacent to the other end of the three-dimensional spiral coil 5a. In this case, the inductor L1 is divided into three sub-inductors, namely the first sub-inductor L... 11 Second sub-inductor L 12 and the third sub-inductor L located between the two 13 The third sub-inductor L 13 No current flows through the short circuit; only the first sub-inductor L. 11 Second sub-inductor L 12 .

[0085] Furthermore, when using a single RF power supply 9 to simultaneously output RF power to two three-dimensional spiral coils (5a, 5b), since the current directions in the two coil segments on either side of the conducting position of each three-dimensional spiral coil are opposite, in order to make the magnetic field directions formed by the two coil segments align, such as... Figure 15 As shown, in the three-dimensional spiral coil and the first coil segment (i.e., the first sub-inductor L) 11 A cable (equivalent to inductor L3) is added between one end of the first coil segment and the matching unit 10, and the first coil segment (i.e., the first sub-inductor L) is connected to the matching unit 10. 11 The sum of the lengths of the wire (equivalent to inductance L3) and the second coil segment (i.e., the second sub-inductance L) (H1+H3) is equal to the length of the second coil segment (i.e., the second sub-inductance L). 12The difference between the lengths H1 and H3 (H1+H3-H2) of the first coil segment (i.e., the first sub-inductor L3) and H2 is equal to half the wavelength of the RF signal output by the RF power supply, so that the phase difference of the RF signals simultaneously output by the RF power supply 9 to both ends of each three-dimensional spiral coil is equal to half the period of the RF signal. In practical applications, the difference (H1+H3-H2) can be made equal to half the wavelength of the RF signal output by the RF power supply by adjusting the length H3 of the cable (equivalent to inductor L3). For example, if the RF frequency of the RF power supply 9 is 13.56MHz, then according to the formula c=λf (where c represents the speed of light, for example, 300000km / s, λ represents the wavelength of the RF signal, and f represents the RF frequency of the RF power supply 9), the wavelength λ can be calculated to be 22.12m, and thus the difference (H1+H3-H2) can be calculated to be 11.06m. 11 The length H1 of the second coil segment (i.e., the second sub-inductor L) and the second coil segment (i.e., the second sub-inductor L) 12 Since the length H2 of the cable is known, the required length H3 of the cable (equivalent to inductance L3) can be calculated.

[0086] Similarly, the three-dimensional spiral coil 5b is equivalent to an inductor L2. The coil segments between the two ends of the three-dimensional spiral coil 5b and the grounding components 6b adjacent to the two ends are respectively the first coil segment and the second coil segment, which are equivalent to the first sub-inductor L2. 21 Second sub-inductor L 22 Moreover, the second coil segment (i.e., the second sub-inductor L) 22 Relative to the first coil segment (i.e., the first sub-inductor L) 21 () Closer to the center of dielectric cavity 1. If there are two grounding elements 6b, such as Figure 16 As shown, one grounding component 6b is adjacent to one end of the three-dimensional spiral coil 5b, and the other grounding component 6b is adjacent to the other end of the three-dimensional spiral coil 5b. In this case, the inductor L2 is divided into three sub-inductors, namely the first sub-inductor L... 21 Second sub-inductor L 22 and the third sub-inductor L located between the two 23 The third sub-inductor L 23 No current flows through the short circuit; only the first sub-inductor L. 21 Second sub-inductor L 22 .

[0087] In some alternative embodiments, such as Figure 14 As shown, adjustable capacitors are provided on the circuit between each end of each three-dimensional spiral coil and the matching unit 10 connected thereto. For example, as Figure 14As shown, the two three-dimensional spiral coils (5a, 5b) have a total of four RF feed points, and four adjustable capacitors (C) are respectively set on the four circuits between the four coils and the matching unit 10. 51 ~C 54 ), by adjusting four adjustable capacitors (C 51 ~C 54 Adjusting at least one of the components can distribute the RF power output from the RF power supply 9. Specifically, if it is necessary to increase the proportion of power distributed on the circuit between one of the RF feed terminals and the matching unit 10, it is necessary to reduce the impedance of the circuit. In this case, the impedance of the circuit can be reduced by increasing the capacitance of the circuit through an adjustable capacitor.

[0088] In some other alternative embodiments, such as Figure 17 As shown, the upper RF source may also include two RF power supplies (9a, 9b) and two matching circuits (10a, 10b). Each of the two three-dimensional spiral coils (5a, 5b) has one end electrically connected to one of the two RF power supplies (9a, 9b) through one of the two matching circuits (10a, 10b), and the other end electrically connected to the other of the two RF power supplies (9a, 9b) through the other of the two matching circuits (10a, 10b). When using two RF power supplies (9a, 9b) to simultaneously output RF power to the two three-dimensional spiral coils (5a, 5b), since the current directions in the two coil segments on both sides of the electrically conductive position of each three-dimensional spiral coil are opposite, in order to make the magnetic field directions formed by the two coil segments consistent, the phase difference of the RF signals output by the two RF power supplies (9a, 9b) is equal to half the period of the RF signal. In practical applications, the phase difference of the RF signals output by the two RF power supplies (9a, 9b) can be adjusted by adjusting the crystal oscillators in the two RF power supplies (9a, 9b).

[0089] In summary, the semiconductor process equipment provided by this invention has two ends of a three-dimensional spiral coil that are both electrically connected to an upper radio frequency source as radio frequency feed-in terminals. The coil grounding device is electrically connected to the three-dimensional spiral coil in an adjustable position, and the three-dimensional spiral coil is grounded through the coil grounding device. The grounding position is located between the two ends of the three-dimensional spiral coil. Since the position of the coil grounding device is adjustable, the electrical conduction position as the radio frequency feed-out terminal is adjustable. By adjusting the electrical conduction position, the plasma distribution can be adjusted, thereby increasing the means of adjusting the uniformity of plasma distribution and improving the flexibility of process adjustment. This can improve the uniformity of plasma distribution to meet the process uniformity requirements of large-size chambers.

[0090] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A semiconductor process apparatus, characterized in that, The device includes a process chamber, an upper radio frequency source, a radio frequency coil structure, and a coil grounding device. The process chamber comprises a process cavity and a dielectric cavity, with the dielectric cavity located above the process cavity and sealed to it. The inner diameter of the dielectric cavity increases from top to bottom. The radio frequency coil structure includes a three-dimensional spiral coil that surrounds the dielectric cavity, with its inner diameter increasing from top to bottom. Both ends of the three-dimensional spiral coil are electrically connected to the upper radio frequency source. The coil grounding device is electrically connected to the three-dimensional spiral coil in an adjustable position, and the three-dimensional spiral coil is grounded through the coil grounding device. The grounding position is located between the two ends of the three-dimensional spiral coil, so as to adjust the distribution of plasma along the radial direction of the radio frequency coil structure by adjusting the grounding position.

2. The semiconductor process equipment according to claim 1, characterized in that, The coil grounding device includes a grounding component and a conductive fixing component. The conductive fixing component is connected to the three-dimensional spiral coil in an adjustable position, and the conductive fixing component is electrically connected to the three-dimensional spiral coil. The conductive fixing member is provided with a first mating part, and the grounding member is provided with a second mating part, and the first mating part and the second mating part are detachably electrically connected.

3. The semiconductor process equipment according to claim 2, characterized in that, One of the first mating part and the second mating part is a slot, and the other of the first mating part and the second mating part is a plug-in, which is plugged into the slot.

4. The semiconductor process equipment according to claim 2, characterized in that, The conductive fixing member is slidably connected to the three-dimensional spiral coil along the spiral direction of the three-dimensional spiral coil, and the conductive fixing member is provided with a fastening structure for fixing the conductive fixing member to the three-dimensional spiral coil when the conductive fixing member slides to a preset grounding position.

5. The semiconductor process equipment according to claim 2, characterized in that, The coil grounding device further includes a slide rail, which is fixed above the dielectric cavity and spaced apart on the side of the three-dimensional spiral coil away from the dielectric cavity. The slide rail is provided with a groove that extends along a designated path. The grounding member slides in conjunction with the groove. The designated path is configured to allow the grounding member to slide along the groove to a position corresponding to the conductive fixing member, so that the second mating part can be connected to the first mating part.

6. The semiconductor process equipment according to claim 5, characterized in that, The specified path extends along the helical direction of the three-dimensional spiral coil; or, it extends radially along the three-dimensional spiral coil and at an angle relative to the horizontal plane.

7. The semiconductor process equipment according to claim 2, characterized in that, The coil grounding device includes multiple grounding components and multiple conductive fixing components. The multiple conductive fixing components are connected to different positions of the three-dimensional spiral coil in an adjustable manner. Each grounding component is electrically connected to the corresponding conductive fixing component, so that the three-dimensional spiral coil is grounded at different positions simultaneously.

8. The semiconductor process equipment according to any one of claims 1-7, characterized in that, There are two three-dimensional spiral coils, and the turns of the two three-dimensional spiral coils are arranged side by side in the horizontal direction in a one-to-one correspondence. The two three-dimensional spiral coils are symmetrical with respect to the axial direction of the dielectric cavity and the current direction is the same. Both ends of each three-dimensional spiral coil are electrically connected to the upper radio frequency source. The connection position of one of the three-dimensional spiral coils to the corresponding coil grounding device is symmetrical with respect to the axial direction of the dielectric cavity as is the connection position of the other three-dimensional spiral coil to the corresponding coil grounding device, so that the two three-dimensional spiral coils are grounded at positions symmetrical with respect to the axial direction of the dielectric cavity.

9. The semiconductor process equipment according to claim 8, characterized in that, Each coil grounding device corresponding to each of the three-dimensional spiral coils includes a grounding component and a conductive fixing component. The conductive fixing component is connected to the three-dimensional spiral coil and is electrically connected to the three-dimensional spiral coil. The conductive fixing component is provided with a first mating part, and the grounding component is provided with a second mating part. The first mating part and the second mating part are detachably electrically connected. The two three-dimensional spiral coils each have multiple conductive fasteners of the same number. The different conductive fasteners on each three-dimensional spiral coil are located at different positions between the two ends of the three-dimensional spiral coil. The positions of the conductive fasteners on one three-dimensional spiral coil and the positions of the conductive fasteners on the other three-dimensional spiral coil are symmetrical with respect to the axial direction of the medium cavity. The grounding element on each of the three-dimensional spiral coils is selectively connected to any one of the plurality of conductive fixing elements, and the conductive fixing element connected to the grounding element on one of the three-dimensional spiral coils is symmetrical with respect to the axial direction of the dielectric cavity to the conductive fixing element connected to the grounding element on the other three-dimensional spiral coil.

10. The semiconductor process equipment according to any one of claims 1-7, characterized in that, The upper radio frequency source includes two radio frequency power supplies and two matching circuits; one end of the three-dimensional spiral coil is connected to one of the radio frequency power supplies through one of the matching circuits, and the other end of the three-dimensional spiral coil is electrically connected to the other radio frequency power supply through the other matching circuit; or... The upper radio frequency source includes a radio frequency power supply and a matching unit, and both ends of the three-dimensional spiral coil are electrically connected to the radio frequency power supply through the matching unit.

11. The semiconductor process equipment according to claim 10, characterized in that, Each end of the three-dimensional spiral coil and the circuit connected to it via the matching device are provided with an adjustable capacitor.

12. The semiconductor process equipment according to claim 10, characterized in that, The upper radio frequency source includes a radio frequency power supply and a matching unit, and both ends of the three-dimensional spiral coil are electrically connected to the radio frequency power supply through the matching unit; The two ends of the three-dimensional spiral coil and the coil segment between the grounding member adjacent to the two ends are respectively the first coil segment and the second coil segment; Wherein, the first coil segment is electrically connected to the matching unit via a cable, and the absolute value of the difference between the sum of the lengths of the first coil segment and the cable and the length of the second coil segment is equal to half the wavelength of the radio frequency signal output by the radio frequency power supply; or, The second coil segment is electrically connected to the matching unit via the cable, and the difference between the sum of the lengths of the second coil segment and the cable and the length of the first coil segment is equal to half the wavelength of the radio frequency signal output by the radio frequency power supply.

13. The semiconductor process equipment according to claim 10, characterized in that, The upper radio frequency source includes two radio frequency power supplies and two matching units; One end of the three-dimensional spiral coil is connected to one of the radio frequency power supplies through one of the matching devices, and the other end of the three-dimensional spiral coil is electrically connected to another radio frequency power supply through another matching device; The phase difference between the radio frequency signals output by the two radio frequency power supplies is equal to half the period of the radio frequency signal.

Images