Lower electrode device and semiconductor processing equipment

Abstract

The utility model provides a lower electrode device and semiconductor processing equipment, the lower electrode device comprises a chuck, and a plurality of gas paths and a plurality of radio frequency introduction assemblies distributed around the center of the chuck, the chuck is used for bearing a plurality of wafers, the plurality of gas paths are used for being in one-to-one correspondence with the plurality of wafers, the gas paths are arranged on the chuck and penetrate through the thickness of the chuck, and the radio frequency introduction assemblies are arranged on the chuck. A gas outlet of the gas circuit is positioned in a corresponding wafer placing area on the chuck; the radio frequency feed-in pieces are used for being in one-to-one correspondence with a plurality of wafers, the radio frequency feed-in pieces are in conductive contact with the bottom of the chuck, and the orthographic projection of the contact position on the top surface of the chuck is located in the center of a corresponding wafer placing area borne on the chuck. Therefore, the gas medium flowing out of the gas path can be blown to the lower part of the corresponding wafer for heat exchange, the temperature distribution uniformity of the wafer is high, the distribution uniformity of the magnetic field is high, the process uniformity is greatly improved, and the product yield is high.

Description

Technical Field

[0001] The utility model relates to the field of semiconductor manufacturing, in particular to a lower electrode device and semiconductor processing equipment. Background Art

[0002] In order to improve production capacity, the lower electrode device of semiconductor processing equipment such as Micro LED etching equipment and epitaxial equipment can carry multiple wafers at the same time to complete the semiconductor process of multiple wafers at the same time. However, in actual application, the process uniformity of each wafer is poor and the product yield is low. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art, and proposes a lower electrode device and semiconductor processing equipment.

[0004] In a first aspect, the utility model provides a lower electrode device, comprising: a chuck, and a plurality of gas paths and a plurality of radio frequency feed-ins distributed around the center of the chuck, the chuck being used to carry a plurality of wafers, the plurality of gas paths being used to correspond one-to-one to the plurality of wafers, the gas paths being arranged on the chuck and penetrating the thickness of the chuck, the gas outlets of the gas paths being located in a region on the chuck carrying the corresponding wafers for placement; the plurality of radio frequency feed-ins being used to correspond one-to-one to the plurality of wafers, the radio frequency feed-ins being in conductive contact with the bottom of the chuck and the orthographic projection of the contact position on the top surface of the chuck being located in the center of a region on the chuck carrying the corresponding wafers for placement.

[0005] In an implementation of the first aspect of the utility model, the lower electrode device also includes a base, which is stacked below the chuck; a plurality of first channels are provided on the base, each first channel corresponds to each gas circuit one by one, and the inlet end of each first channel is used to connect with the gas source, and the outflow end is connected with the gas inlet of the corresponding gas circuit.

[0006] In an implementation of the first aspect of the utility model, the lower electrode device also includes an interface disk, which is stacked below the base; a plurality of second channels are provided on the interface disk, and the plurality of second channels correspond one-to-one to the plurality of first channels, and the inlet end of each second channel is used to connect with the gas source, and the outlet end is connected with the inlet end of the corresponding first channel.

[0007] In an implementation of the first aspect of the utility model, a first outer sealing ring and a plurality of first inner sealing rings are provided between the top surface of the base and the lower surface of the chuck, the first outer sealing ring is provided outside all the first inner sealing rings, the plurality of first inner sealing rings correspond to the plurality of gas paths one by one, and each first inner sealing ring is provided around an air inlet of a corresponding gas path; and / or,

[0008] A second outer sealing ring and multiple second inner sealing rings are provided between the top surface of the interface plate and the bottom surface of the base. The second outer sealing ring is arranged on the outside of all the second inner sealing rings. The multiple second inner sealing rings correspond one-to-one to the multiple first channels. Each second inner sealing ring is arranged around the inflow end of the corresponding first channel.

[0009] In an implementation of the first aspect of the utility model, the lower electrode device further includes an introduction member, and the plurality of RF feedthroughs are electrically connected to the output end of the RF power supply through the same introduction member; or, the plurality of RF feedthroughs are electrically connected to the output end of the RF power supply respectively.

[0010] In an implementation of the first aspect of the utility model, when multiple RF feed-throughs are electrically connected to the output end of the RF power supply through the same introduction component, the lower electrode device also includes a base arranged below the chuck, and the top surface of the base and the lower surface of the chuck together form an installation cavity, and the multiple RF feed-throughs are all arranged in the installation cavity; a first through hole is provided on the base, and the top end of the introduction component extends into the installation cavity through the first through hole.

[0011] In an implementation of the first aspect of the utility model, a groove is formed on the top surface of the base, and the groove wall and the lower surface of the chuck together form a mounting cavity.

[0012] In an implementation of the first aspect of the utility model, the lower electrode device also includes a plurality of conduits corresponding one-to-one to the plurality of gas paths, and the gas inlets of the gas paths are connected to the gas source through the corresponding conduits; the lower electrode device also includes a plurality of flow control devices corresponding one-to-one to the plurality of conduits, and the flow control devices are used to adjust the cooling gas flow passing through the corresponding conduits.

[0013] In an implementation of the first aspect of the utility model, the flow control device includes a pressure controller and a flow control valve arranged on the catheter, the pressure controller is used to control the gas pressure of the catheter, and the flow control valve is used to adjust the gas flow of the catheter; or, the flow control device includes a mass flow controller arranged on the catheter.

[0014] In a second aspect, the utility model further provides a semiconductor processing equipment, comprising: a cavity and any one of the lower electrode devices provided in the first aspect of the utility model, at least part of the lower electrode device is located in the cavity, and the lower electrode device is used to carry a wafer.

[0015] The utility model has the following beneficial effects:

[0016] The lower electrode device provided by the utility model is provided with a plurality of mutually independent gas paths, and the plurality of gas paths correspond one to one with the plurality of wafers carried by the chuck, so that each gas path can individually purge the gas medium under the corresponding wafer, so as to ensure that each part on each wafer can exchange heat with the gas medium, thereby improving the temperature uniformity of the wafer.

[0017] At the same time, by designing the contact position of each RF feed-through and the chuck so that the projection on the top surface of the chuck is located at the center of each placement area, the magnetic field generated by a placement area for carrying a corresponding chip is symmetrically distributed about the center of the placement area, and the distribution uniformity of the magnetic field is high.

[0018] In this way, the temperature uniformity of the wafer carried is improved, and the distribution uniformity of the magnetic field is improved. Therefore, when the semiconductor processing equipment with the lower electrode device of the utility model is used to process the wafer, the process uniformity is greatly improved, which is conducive to improving the product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic cross-sectional view of a lower electrode device provided for some related technologies;

[0020] Figure 2 for Figure 1 A top view of the lower electrode device shown;

[0021] Figure 3 for Figure 1 A schematic diagram of the cooperation between the chuck of the lower electrode device and the wafer carried thereon;

[0022] Figure 4 for Figure 1 A schematic diagram of the distribution of the magnetic field generated on the chuck in the lower electrode device shown;

[0023] Figure 5 A schematic diagram of a semiconductor processing device provided in an embodiment of the present application;

[0024] Figure 6 A front view of a lower electrode device provided in an embodiment of the present application;

[0025] Figure 7 A schematic cross-sectional view of a lower electrode device provided in an embodiment of the present application;

[0026] Figure 8 A schematic cross-sectional view of a lower electrode device provided in an embodiment of the present application;

[0027] Fig. 9 for Figure 6 A schematic diagram of the distribution of the magnetic field generated by any placement area on the chuck in the lower electrode device shown;

[0028] Fig.10 for Figure 7 The schematic diagram of the structure of the connection between the introduction column and the radio frequency feed-in component in the lower electrode device is shown.

[0029] Description of reference numerals:

[0030] 1000-Semiconductor processing equipment;

[0031] 100- cavity;

[0032] 200-upper electrode device;

[0033] 300-lower electrode device; 310-tray; 311-bearing area; 312-gas storage space; 320-chuck; 321-gas path; 322-first inner sealing ring; 323-first outer sealing ring; 330-base; 331-first through hole; 332-groove; 333-first channel; 334-second inner sealing ring; 335-second outer sealing ring; 340-interface plate; 341-second through hole; 342-second channel; 343-third sealing ring; 350-RF power supply; 351-matching device; 360-catheter; 361-mass flow controller; 370-RF introduction component; 371-RF feed-in piece; 372-introduction piece; 373-top plate; 374-conductive piece; 380-focusing ring; 390-insulating ring. DETAILED DESCRIPTION

[0034] Taking etching equipment as an example of semiconductor processing equipment, etching uniformity is closely related to the uniformity of energy fed into the lower electrode device and the temperature uniformity of the wafer.

[0035] Figure 1 A cross-sectional schematic diagram of a lower electrode device provided for some related technologies, Figure 2 for Figure 1 A top view of the lower electrode device shown, Figure 3 for Figure 1 The schematic diagram of the lower electrode device chuck and the wafer being carried is shown. Figure 1 and Figure 2 , lower electrode device 300a

[0036] The chuck 320a and the tray 310a are included. The chuck 320a is used to carry the tray 310a. The tray 310a has a carrying surface for carrying the wafer 400. Figure 2 An example is shown in which two wafers 400 are carried on the carrying surface of the tray 310 a.

[0037] like Figure 1As shown, a gas storage space 312a is defined between the bottom surface of the tray 310a and the upper surface of the chuck 320a, and a gas path 321a is provided inside the chuck 320a. The central axis of the gas path 321a is coaxially arranged with the central axis of the chuck 320a, and the gas outlet of the gas path 321a is connected with the gas storage space 312a. The gas inlet of the gas path 321a is used to be connected with the gas source to purge the gas medium into the gas storage space 312a. The gas medium exchanges heat with the tray 310a, and the tray 310a exchanges heat with the wafer 400 to achieve temperature regulation of the wafer 400 during the process.

[0038] Reference Figure 2 and Figure 3 When the lower electrode device 300a is used to prepare a semiconductor device, the tray 310a carries two wafers 400 at the same time, and the two wafers 400 are symmetrical with respect to the tray 310a ( Figure 3 00). In this way, the back of the two wafers 400 and the position of the top surface of the tray 310a corresponding to the gas storage space 312a are in contact with each other in an area equivalent to improve the temperature consistency of the two wafers 400. However, part of the back of each wafer 400 is in contact with the position of the top surface of the tray 310a corresponding to the gas storage space 312a, and the remaining part is not in contact with the position of the top surface of the tray 310a corresponding to the gas storage space 312a. Then, the heat exchanged between each part of each wafer 400 and the gas medium is different, which leads to low temperature consistency of each region of each wafer 400, thereby resulting in poor intra-chip etching uniformity of each wafer 400. Moreover, although the back of the two wafers 400 and the position of the top surface of the tray 310a corresponding to the gas storage space 312a are in contact with each other in an area equivalent to each other, it is difficult to accurately control the amount of gas purged to the position of each wafer 400 corresponding to the gas storage space 312a, and thus it is difficult to accurately control the temperature of each wafer 400.

[0039] like Figure 1 As shown in FIG. 1 , the lower electrode device 300a further includes a radio frequency feeder 371a, the top of which is electrically connected to the bottom of the chuck 320a, and the radio frequency feeder 371a is used to load radio frequency power to the chuck 320a to form a magnetic field on the chuck 320a for attracting plasma. After a large number of simulation analyses, the distribution of the magnetic field formed on the chuck 320a of the lower electrode device 300a is as follows: Figure 4 As shown, it can be understood that, since the RF feed-in element 371a deviates from the center of the chuck 320a, the center of the magnetic field deviates from the center of the chuck 320a. In this way, the distribution of the magnetic field formed on the chuck 320a relative to each wafer 400 is also uneven. Figure 4 for Figure 1 A schematic diagram of the distribution of the magnetic field generated on the chuck 320a in the lower electrode device 300a is shown.

[0040] In summary, Figure 1 The lower electrode device 300a provided in the related art has a low uniformity of the magnetic field generated, and at the same time, the temperature uniformity of different regions on each wafer 400 is low. Therefore, when the semiconductor processing equipment having the lower electrode device 300a is used to process the wafer 400, the intra-wafer process uniformity and the inter-wafer process uniformity are both poor.

[0041] In view of this, the present application provides a lower electrode device and a semiconductor processing device. In order to enable those skilled in the art to better understand the technical solution of the present invention, the lower electrode device and the semiconductor processing device provided by the present invention are described in detail below in conjunction with the accompanying drawings.

[0042] The embodiment of the present application provides a semiconductor processing device, which is not limited to an ICP device, but may also be a capacitively coupled plasma (CCP) device or other types of devices. The semiconductor processing device may be used, for example, to prepare Micro LED devices.

[0043] Figure 5 A schematic diagram of a semiconductor processing device provided in an embodiment of the present application. Figure 5 The semiconductor processing equipment 1000 includes a cavity 100, an upper electrode device 200 and a lower electrode device 300. The upper electrode device 200 is arranged at the top of the cavity 100 to excite the reaction gas in the cavity 100 to form plasma. At least part of the lower electrode device 300 is located in the cavity 100. The lower electrode device 300 is used to carry a wafer so that the wafer completes the process in the cavity 100.

[0044] Figure 6 This is a front view of a lower electrode device 300 provided in an embodiment of the present application. Figure 7 A schematic cross-sectional view of a lower electrode device 300 provided in an embodiment of the present application, Figure 8 This is a cross-sectional schematic diagram of a lower electrode device 300 provided in an embodiment of the present application. Figures 6 to 8 The embodiment of the present application further provides a lower electrode device 300 . The lower electrode device 300 includes a chuck 320 , a radio frequency introduction component 370 , and a radio frequency power source 350 disposed outside the cavity 100 .

[0045] Among them, the chuck 320 is used to carry multiple chips, and the number of chips carried by the chuck 320 is not restrictive, for example, it can be 2, 3, 4, etc. The various drawings of the embodiments of the present application show that the chuck 320 can carry two chips as an example, which should not be regarded as a limitation of this embodiment.

[0046] The chuck 320 is also provided with a plurality of gas paths 321 distributed around its center. The number of gas paths 321 is the same as the number of wafers carried by the chuck 320. The plurality of gas paths 321 correspond to the plurality of wafers one by one, and each gas path 321 is independent of each other. Each gas path 321 runs through the thickness of the chuck 320 itself, and the gas inlet of each gas path 321 is connected to the gas source, which is arranged outside the cavity 100 to provide the gas medium, and the gas outlet of each gas path 321 is located in the placement area of ​​the chuck 320 for carrying the wafer corresponding thereto. In this way, each gas path 321 can purge the gas medium under the wafer corresponding thereto separately, and the gas medium and the wafer perform heat exchange to realize the temperature control of the wafer corresponding thereto during the process.

[0047] Exemplarily, the gas medium may be a refrigerant gas, which controls the temperature of the wafer by cooling the wafer. In an alternative example, the gas medium may also be a heat medium gas, which controls the temperature of the wafer by heating the wafer. For example, the gas medium may be an inert gas such as helium or argon, so as to prevent the gas medium from participating in the semiconductor process and affecting the process.

[0048] The above-mentioned RF introduction component 370 includes a plurality of RF feed-ins 371, the number of which is equal to the number of wafers carried by the chuck 320, and the plurality of RF feed-ins 371 correspond one to one with the plurality of wafers, and one end of each RF feed-in 371 is connected to the output end of the RF power supply 350, and the other end is in conductive contact with the bottom of the chuck 320, which is directly opposite to the position of the wafer placement area corresponding thereto. In this way, the RF power supply 350 is electrically connected to a placement area on the chuck 320 for carrying the corresponding wafer through the RF feed-in 371, and is used to provide an RF signal to the placement area, so as to form a magnetic field for attracting plasma in the placement area on the chuck 320. In this way, a plurality of magnetic fields can be formed on the chuck 320, and the plurality of magnetic fields correspond one to one with the plurality of placement areas.

[0049] It should also be pointed out that the orthographic projection of the contact position between each RF feed 371 and the chuck 320 on the top surface of the chuck 320 is located at the center of each placement area. In other words, each RF feed 371 is in conductive contact with the center of the corresponding placement area on the bottom of the chuck 320. Thus, the center of each magnetic field is located at the center of the corresponding placement area, and the magnetic fields are symmetrically distributed about the center of each placement area. It should be pointed out that after a large number of simulation analyses, the distribution of the magnetic field formed on any placement area in the chuck 320 of the lower electrode device 300 of this embodiment is as shown in FIG. Fig. 9As shown, it can be understood that, since the center of each magnetic field in this embodiment coincides with the center of the corresponding placement area, each magnetic field is symmetrically distributed relative to the center of the corresponding placement area, and each magnetic field is evenly distributed relative to the wafer carried by the corresponding placement area. Fig. 9 for Figure 6 A schematic diagram of the distribution of the magnetic field generated by any placement area on the chuck 320 in the lower electrode device 300 is shown.

[0050] Therefore, the lower electrode device 300 provided in this embodiment is provided with a plurality of independent gas circuits 321, and the plurality of gas circuits 321 correspond one-to-one to the plurality of chips carried by the chuck 320, so that each gas circuit 321 can individually purge the gas medium under the corresponding chip, so that there is a purge gas medium between each chip and the corresponding placement area on the chuck 320, so as to ensure that each part of each chip 400 can exchange heat with the gas medium, thereby improving the temperature uniformity of the chip 400.

[0051] Moreover, by designing the contact position of each RF feed-through 371 and the chuck 320 so that the orthographic projection on the top surface of the chuck 320 is located at the center of each placement area, the magnetic field generated by each placement area on the chuck 320 for carrying each chip is symmetrically distributed about the center of the corresponding placement area, and the distribution uniformity of the magnetic field is high.

[0052] In summary, the lower electrode device 300 provided in this embodiment improves the temperature uniformity of the wafer carried, and improves the uniformity of the magnetic field distribution. Therefore, when the semiconductor processing equipment 1000 with the lower electrode device 300 is used to process the wafer, the intra-wafer process uniformity and the inter-wafer process uniformity are greatly improved, which is conducive to improving the product yield.

[0053] As an optional method of the present application, the gas medium flowing out from the gas outlet of the gas path 321 can be directly blown to the back side of the wafer, and at this time the gas medium directly contacts the back side of the wafer for heat exchange.

[0054] As an alternative, see Figure 7 and Figure 8The lower electrode device 300 further includes a tray 310, a chuck 320 is stacked below the tray 310, and the chuck 320 is used to carry the tray 310. The top surface of the tray 310 has multiple carrying areas 311, and each carrying area 311 can correspondingly carry a wafer, so that the tray 310 carries multiple wafers. A plurality of gas storage spaces 312 are defined between the upper surface of the chuck 320 and the bottom surface of the tray 310. The number of gas storage spaces 312 is the same as the number of placement areas and the carrying areas 311. The plurality of gas storage spaces 312 correspond to the plurality of placement areas and the plurality of carrying areas 311 one by one. The gas storage spaces 312 are independent of each other. The orthographic projection of each gas storage space 312 on the top surface of the tray 310 covers a corresponding carrying area 311, and the orthographic projection on the top surface of the chuck 320 covers a corresponding placement area. The orthographic projection of the gas storage space 312 on the top surface of the tray 310 can completely overlap with the corresponding bearing area 311 , and the orthographic projection of the gas storage space 312 on the top surface of the chuck 320 can completely overlap with the corresponding placement area.

[0055] That is, in this embodiment, the gas medium flowing out from the gas outlet of the gas path 321 indirectly exchanges heat with the corresponding wafer through the tray 310 .

[0056] By comparing the above two optional methods, it can be seen that in the embodiment where the gas medium flowing out from the outlet of the gas path 321 is directly blown to the back side of the chip, the gas medium close to the outlet flows faster, and the gas medium away from the outlet flows slower. The flow speed of the gas medium is positively correlated with the gas volume of the gas medium. Therefore, there are differences in the volume of the gas medium blown to various parts of the back side of the chip, which has an adverse effect on the temperature uniformity of the chip.

[0057] It should be understood that in the embodiment where the lower electrode device 300 is further provided with a tray 310, a plurality of gas storage spaces 312 are defined between the tray 310 and the chuck 320, and the orthographic projection of each gas storage space 312 on the top surface of the tray 310 covers a corresponding bearing area 311. In this way, the position where the back of the wafer carried by each bearing area 311 is attached to the bearing area 311 corresponds to the gas storage space 312 located below the bearing area 311, and since the gas medium flowing out of the gas outlet of the gas path 321 diffuses in the corresponding gas storage space 312, the gas in the gas storage space 312 is evenly distributed, which can make the heat exchanged between each part of the wafer and the gas medium the same, so as to further improve the temperature consistency of each area on the wafer.

[0058] As disclosed in the lower electrode device 300, the gas storage space 312 may be realized by a first recessed portion formed on the upper surface of the chuck 320, or by a second recessed portion formed on the bottom surface of the tray 310. Alternatively, a first docking groove may be formed on the upper surface of the chuck 320, and a second docking groove may be formed on the bottom surface of the tray 310, and the first docking groove and the second docking groove are docked and together enclose the gas storage space 312.

[0059] In some embodiments of the present application, the flow rate of the gas medium entering each gas path 321 can be adjusted independently. Figures 1 to 3 Compared with the related technology shown in the figure, the present embodiment adopts this method. By individually adjusting the flow rate of the gas medium entering each gas path 321, the gas volume of the gas medium blown to each chip can be individually and accurately adjusted to be able to adjust the heat exchanged between each chip and the gas medium, thereby achieving accurate control of the temperature of each chip.

[0060] It should be noted that when the flow rate of the gas medium entering each gas path 321 is equal, the heat exchanged between each chip and the gas medium is basically the same, and the temperature of each chip is roughly the same. It can be seen that the use of the lower electrode device 300 of this embodiment can not only make the temperature of each area of ​​each chip uniformly distributed, but also make the temperature between different chips have a high consistency. In this way, it is conducive to improving the process uniformity between different chips (i.e., the process uniformity between chips).

[0061] Exemplarily, the lower electrode device 300 may further include a plurality of conduits 360, the number of which is the same as the number of gas circuits 321 and wafers, the plurality of gas circuits 321 correspond one to one with the plurality of conduits 360, and the gas inlet of each gas circuit 321 is connected to the gas source through a conduit 360. There may be a plurality of gas sources, which are also independent of each other, and each gas source can inflate one or more gas circuits 321 accordingly. Alternatively, there is one gas source, and the inflow end of each conduit 360 is connected to the gas source, so there is no need to set up a plurality of gas sources, which is conducive to cost saving.

[0062] It should be understood that in order to independently adjust the flow of the gas medium entering each gas path 321, the lower electrode device 300 may also include multiple flow control devices corresponding to the multiple conduits, and the flow control devices are used to adjust the flow of the gas medium passing through the corresponding conduits.

[0063] In a first achievable manner, the flow control device may specifically include a mass flow controller (MFC) 361 disposed on the corresponding conduit 360 , and the mass flow controller 361 may be used to control the flow of the gas medium transmitted by the corresponding conduit 360 .

[0064] In a second achievable method, the flow control device may also include a pressure controller and a flow control valve arranged on the conduit 360, the pressure controller is used to control the gas pressure of the corresponding conduit 360, and the flow control valve is used to adjust the gas flow of the corresponding conduit 360.

[0065] Please continue to refer to Figures 6 to 8 In some embodiments, the lower electrode device 300 further includes a base 330, and the base 330 is stacked below the chuck 320. In this example, a plurality of first channels 333 are further provided on the base 330, and the number of the first channels 333 is equal to the number of the gas circuits 321. The plurality of first channels 333 correspond to the plurality of gas circuits 321 one by one, and the inflow end of each first channel 333 is connected to the gas source, and the outflow end is connected to the gas inlet of a corresponding gas circuit 321. In this way, the gas medium provided by the gas source flows into the gas circuit 321 through the first channel 333, and is then purged to the bottom of the corresponding wafer by the gas outlet of the gas circuit 321. By such an arrangement, the present embodiment uses the base 330 to carry the chuck 320 while ensuring that the gas circuit 321 is conductive.

[0066] In order to improve the sealing performance of gas medium transmission, based on the embodiment in which the lower electrode device 300 is provided with a base 330, further, a first outer sealing ring 323 and a plurality of first inner sealing rings 322 are provided between the top surface of the base 330 and the lower surface of the chuck 320, the number of the first inner sealing rings 322 is equal to the number of the gas paths 321, the plurality of first inner sealing rings 322 correspond one-to-one to the plurality of gas paths 321, each first inner sealing ring 322 is arranged around the air inlet of the corresponding gas path 321, the first inner sealing ring 322 seals the connection between the outflow end of the first channel 333 and the air inlet of the gas path 321, so as to reduce the possibility of gas medium escaping from the connection between the outflow end of the first channel 333 and the air inlet of the gas path 321.

[0067] The first outer sealing ring 323 is arranged around the outside of all the first inner sealing rings 322 , thereby strengthening the contact sealing between the top surface of the base 330 and the lower surface of the chuck 320 , which is conducive to further reducing the risk of gas medium escaping from between the base 330 and the chuck 320 .

[0068] Please continue to refer to Figures 6 to 8On the basis of the embodiment in which the lower electrode device 300 is provided with the base 330, the lower electrode device 300 may further include an interface plate 340, which is stacked below the base 330. In this example, a plurality of second channels 342 are also provided on the interface plate 340, and the number of the second channels 342 is equal to the number of the first channels 333 and the number of the gas circuits 321. The plurality of second channels 342 correspond to the plurality of first channels 333 one by one, and the inflow end of each second channel 342 is connected to the gas source, and the outflow end is connected to the inflow end of the corresponding first channel 333. In this way, the gas medium provided by the gas source flows into the first channel 333 via the second channel 342, and then flows into the gas circuit 321 along the first channel 333, and then is purged to the bottom of the corresponding wafer by the gas outlet of the gas circuit 321. By such an arrangement, the present embodiment uses the interface plate 340 to carry the base 330 while ensuring that the gas circuit 321 is conductive.

[0069] In order to improve the sealing performance of gas medium transmission, based on the embodiment in which the lower electrode device 300 is provided with an interface disk 340, further, a second outer sealing ring 335 and a plurality of second inner sealing rings 334 are provided between the top surface of the interface disk 340 and the bottom surface of the base 330, the number of the second inner sealing rings 334 is equal to the number of the first channels 333, the plurality of second inner sealing rings 334 correspond one-to-one to the plurality of first channels 333, each second inner sealing ring 334 is arranged around the inflow end of the corresponding first channel 333, the second inner sealing ring 334 seals the connection between the outflow end of the second channel 342 and the inflow end of the first channel 333, so as to reduce the possibility of gas medium escaping from the connection between the outflow end of the second channel 342 and the inflow end of the first channel 333.

[0070] The second outer sealing ring 335 is arranged around the outside of all the second inner sealing rings 334 , thereby strengthening the contact sealing between the bottom surface of the base 330 and the top surface of the interface plate 340 , which is beneficial to further reduce the risk of gas medium escaping from between the base 330 and the interface plate 340 .

[0071] In some embodiments, in an embodiment where the lower electrode device 300 is provided with an interface plate 340 and a conduit 360, a third sealing ring 343 may also be arranged around the outer side of the connection between the inflow end of each second channel 342 and the conduit 360. The third sealing ring 343 seals the connection between the inflow end of the second channel 342 and the conduit 360, so as to reduce the possibility of gas medium escaping from the connection between the inflow end of the second channel 342 and the conduit 360, thereby further improving the sealing of the gas medium transmission.

[0072] It is understandable that the implementation of connecting the RF feedthrough 371 to the output end of the RF power source 350 includes but is not limited to the following embodiments.

[0073] For example, in some embodiments, each RF feedthrough 371 is connected to an output terminal of the RF power source 350 .

[0074] Fig.10 for Figure 7 Schematic diagram of the structure of the lower electrode device 300 in which the lead-in element 372 is connected to the RF feed-in element 371. For another example, in some embodiments, refer to Figure 7 and Fig.10 The RF introduction component 370 also includes an introduction member 372, and multiple RF feed members 371 are electrically connected to the output end of the RF power supply 350 through the same introduction member 372, which is conducive to simplifying the circuit connecting the RF power supply 350 and the RF feed member 371.

[0075] The introduction member 372 mentioned in the present application can be specifically implemented as Figure 7 and Fig.10 The cylindrical structure shown may also be implemented as a prismatic structure, a plate-like structure or other structures, and this embodiment does not impose any specific limitation on this.

[0076] In the embodiment where a plurality of RF feedthroughs 371 are electrically connected to the output end of the RF power source 350 through the same leadthrough 372, one end of the RF feedthrough 371 is in conductive contact with the bottom of the chuck 320, and the other end is connected to the leadthrough 372. When the lower electrode device 300 is provided with a base 330 and an interface plate 340, the other end of the RF feedthrough 371 can pass through the base 330 and the interface plate 340 in sequence, extend to the bottom of the interface plate 340, and then be connected to the leadthrough 372. At this time, the leadthrough 372 is located below the interface plate 340.

[0077] Or, according to Figure 7 In the example shown, the top surface of the base 330 and the lower surface of the chuck 320 may jointly form a mounting cavity, all RF feedthroughs 371 are arranged in the mounting cavity, one end of the lead-in 372 is located in the mounting cavity, and the other end extends out of the mounting cavity to be connected to the RF power source 350. In this technical solution, when the lower electrode device 300 is also provided with a base 330, a first through hole 331 is provided on the base 330, and the top end of the lead-in 372 passes through the first through hole 331 and extends into the mounting cavity to be connected with the RF feedthrough 371. When the lower electrode device 300 is also provided with an interface disk 340, a second through hole 341 is provided on the interface disk 340, and the central axis of the second through hole 341 is coaxially arranged with the central axis of the first through hole 331. After the top end of the lead-in 372 passes through the second through hole 341, it passes through the first through hole 331 to extend into the mounting cavity. With this design, the installation cavity provides installation space for the RF feedthrough 371 , so that the RF feedthrough 371 does not occupy additional space.

[0078] In one possible approach, Figure 7 and Figure 8 As shown, a groove 332 is formed on the top surface of the base 330, and the groove wall of the groove 332 and the lower surface of the chuck 320 together form a mounting cavity. In this way, the RF feed 371 is mounted in the groove 332 at the bottom of the chuck 320.

[0079] In another feasible manner, the groove 332 is replaced by being arranged on the lower surface of the chuck 320. In this case, the groove wall of the groove 332 and the top surface of the base 330 jointly define a mounting cavity. In this way, the RF feed 371 is installed in the groove 332 on the top of the base 330.

[0080] In another feasible manner, a third docking groove is formed on the lower surface of the chuck 320, and a fourth docking groove is formed on the top surface of the base 330. When the chuck 320 is stacked on the base 330, the third docking groove and the third docking groove are docked and together form a mounting cavity. In this way, part of the RF feedthrough 371 is accommodated in the third docking groove at the bottom of the chuck 320, and part of it is accommodated in the fourth docking groove at the top of the base 330.

[0081] Please continue to refer to Figures 6 to 8 On the basis of the embodiment in which the RF introduction component 370 is further provided with an introduction member 372, the central axis of the introduction member 372 can be coaxially arranged with the central axis of the chuck 320, and a plurality of RF feed-throughs 371 are spaced and evenly distributed around the central axis of the introduction member 372 (and the central axis of the chuck 320). In this way, a plurality of wafers are spaced and evenly distributed around the central axis of the chuck 320. In this way, the magnetic fields formed by each placement area on the chuck 320 are not only symmetrically distributed about the center of the corresponding placement area, but all magnetic fields are also symmetrically distributed about the center of the chuck 320.

[0082] The lower electrode device 300 of this embodiment can not only make the magnetic field corresponding to each wafer evenly distributed, but also because the magnetic fields formed in each placement area are symmetrically distributed about the center of the chuck 320, the magnetic fields between the wafers have high consistency. This is conducive to improving the process uniformity between different wafers (i.e., process uniformity between wafers).

[0083] Please combine Figure 7 , Figure 8 and Fig.10, the extension direction of the RF feed 371 can be parallel to the central axis of the chuck 320, and the bottom end of each RF feed 371 is connected to the introduction member 372 through the conductive member 374. Here, the conductive member 374 is also provided with a plurality of conductive members 374, and the number of conductive members 374 is consistent with the number of RF feed 371, and the plurality of conductive members 374 corresponds to the plurality of RF feed 371 one by one. In this embodiment, the RF signal provided by the RF power supply 350 is guided to the conductive member 374 through the introduction member 372, and then loaded to the corresponding placement area through the corresponding RF feed 371. The conductive member 374 can be, for example, a columnar structure, or a plate-like structure or a block structure, and this embodiment does not make specific restrictions on this. Of course, in other embodiments of the present application, the extension direction from the bottom end to the top end of the RF feed 371 can also be inclined to the chuck 320.

[0084] In a specific example, Fig.10 As shown, the lower electrode device 300 may further include a top plate 373 , which is fixedly connected to the top of the introduction member 372 , and one end of each conductive member 374 is connected to the top plate 373 and the other end is fixedly connected to the bottom end of the corresponding RF feed member 371 .

[0085] In general, the lower electrode device 300 of this embodiment is preferably an axisymmetric structure, so that the RF introduction component 370 is also an axisymmetric structure, which is conducive to ensuring that the magnetic field formed in each placement area has a high consistency.

[0086] In the lower electrode device 300 disclosed herein, Figure 6 As shown, the RF introduction component 370 also includes a matcher 351, and the RF power supply 350 is electrically connected to the introduction member 372 through the matcher 351. In this way, the RF signal provided by the RF power supply 350 is guided to each RF feed member 371 via the matcher 351 and the introduction member 372, and then applied to each placement area via the RF feed member 371. Among them, the matcher 351 can be used to adjust the load impedance of the RF power supply 350.

[0087] In any of the above embodiments, the lower electrode device 300 may further include a focusing ring 380, which is disposed around the outer circumference of the tray 310 to confine the plasma above the chuck 320 so that the plasma can effectively act on the wafer.

[0088] In any of the above embodiments, the lower electrode device 300 may further include an insulating ring 390, which is disposed around the outer periphery of the chuck 320. When the lower electrode device 300 is provided with both the focusing ring 380 and the insulating ring 390, the insulating ring 390 is also disposed around the outer periphery of the focusing ring 380.

[0089] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but 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 lower electrode device, characterized in that: include: A chuck for holding multiple wafers; A plurality of gas paths are distributed around the center of the chuck, the plurality of gas paths are used to correspond to the plurality of wafers one by one, the gas paths are arranged on the chuck and penetrate the thickness of the chuck, and the gas outlets of the gas paths are located in the corresponding wafer placement area on the chuck; as well as A plurality of RF feed-ins are distributed around the center of the chuck, the plurality of RF feed-ins are used to correspond one-to-one to the plurality of wafers, the RF feed-ins are in conductive contact with the bottom of the chuck, and the orthographic projection of the contact position on the top surface of the chuck is located at the center of the corresponding wafer placement area on the chuck.

2. The lower electrode device according to claim 1, characterized in that: Also includes a base, the base is stacked below the chuck; The base is provided with a plurality of first channels, each of which corresponds to each of the gas circuits one by one, and the inflow end of each of the first channels is used to communicate with the gas source, and the outflow end is communicated with the gas inlet of the corresponding gas circuit.

3. The lower electrode device according to claim 2, characterized in that: Also included is an interface tray, which is stacked below the base; The interface disk is provided with a plurality of second channels, and the plurality of second channels correspond one-to-one to the plurality of first channels. The inflow end of each second channel is used to communicate with the gas source, and the outflow end is communicated with the inflow end of the corresponding first channel.

4. The lower electrode device according to claim 3, characterized in that: A first outer sealing ring and a plurality of first inner sealing rings are provided between the top surface of the base and the lower surface of the chuck, the first outer sealing ring is provided outside all the first inner sealing rings, the plurality of first inner sealing rings correspond to the plurality of gas paths one by one, and each of the first inner sealing rings is provided around an air inlet of the corresponding gas path; and / or, A second outer sealing ring and a plurality of second inner sealing rings are provided between the top surface of the interface plate and the bottom surface of the base. The second outer sealing ring is provided on the outside of all the second inner sealing rings. The plurality of second inner sealing rings correspond one-to-one to the plurality of first channels. Each second inner sealing ring is provided around the inflow end of the corresponding first channel.

5. The lower electrode device according to claim 1, characterized in that: It also includes an introduction member, wherein the plurality of radio frequency feed-in members are electrically connected to the output end of the radio frequency power supply through the same introduction member; Alternatively, the plurality of RF feedthroughs are electrically connected to output ends of the RF power supply respectively.

6. The lower electrode device according to claim 5, characterized in that: When the plurality of RF feedthroughs are electrically connected to the output end of the RF power supply through the same introduction member, the lower electrode device further comprises a base disposed below the chuck, the top surface of the base and the lower surface of the chuck together enclose a mounting cavity, and the plurality of RF feedthroughs are all disposed in the mounting cavity; The base is provided with a first through hole, and the top end of the introduction member passes through the first through hole and extends into the installation cavity.

7. The lower electrode device according to claim 6, characterized in that: A groove is formed on the top surface of the base, and the groove wall of the groove and the lower surface of the chuck together form the installation cavity.

8. The lower electrode device according to claim 1, characterized in that: Also included are a plurality of conduits corresponding to the plurality of gas circuits one by one, wherein the gas inlets of the gas circuits are connected to a gas source through the corresponding conduits; The lower electrode device also includes a plurality of flow control devices corresponding one-to-one to the plurality of conduits, and the flow control devices are used to adjust the flow of cooling gas passing through the corresponding conduits.

9. The lower electrode device according to claim 8, characterized in that: The flow control device comprises a pressure controller and a flow control valve arranged on the conduit, wherein the pressure controller is used to control the gas pressure of the conduit, and the flow control valve is used to adjust the gas flow of the conduit; Alternatively, the flow control device comprises a mass flow controller arranged on the conduit.

10. A semiconductor processing equipment, characterized in that: include: Cavity; as well as The lower electrode device according to any one of claims 1 to 9, wherein at least a portion of the lower electrode device is located within the cavity.

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