Semiconductor processing apparatus and lower electrode arrangement therefor

Abstract

The application provides a semiconductor process equipment and a lower electrode device thereof, and relates to the field of semiconductor manufacturing. A connecting mechanism is arranged. A radio frequency adapter in the connecting mechanism electrically connects a radio frequency transmission member with a chuck. Radio frequency is fed into the chuck through the radio frequency transmission member and the radio frequency adapter. A first adapter circuit in the connecting mechanism guides a first alternating current signal output by a first cable into a first heating element in the chuck, thereby realizing the heating function of the chuck. A shielding cavity is arranged between the radio frequency adapter and the chuck. A first circuit adapter plate is arranged in the shielding cavity, thereby avoiding the interference of radio frequency on the first circuit adapter plate. The application cancels the resin adapter plate between the ceramic insulating disc and the chuck. The adapter circuit is supported and fixed by the first circuit adapter plate. The space where the resin adapter plate is arranged is filled with air. The dielectric constant of air is smaller than that of resin, thereby reducing the ground capacitance of the chuck.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing, and in particular, to a lower electrode device. The present application also relates to a semiconductor process equipment comprising the lower electrode device. Background Art

[0002] Currently, plasma etchers are used to remove excess material, such as semiconductors, that is pre-designed to meet the processing requirements, creating grooves that meet the corresponding process requirements and providing a foundation for subsequent processes. The plasma etcher chamber is in a vacuum state. Before etching, the wafer to be processed is placed above the lower electrode. During processing, the lower electrode holds the wafer in place, and process gas is injected into the chamber through a nozzle at the center of the dielectric window. A high-frequency power supply is applied to the upper electrode, ionizing the process gas to form a plasma, completing the electrochemical processing of the exposed wafer.

[0003] In existing technology, wire routing must be completed within an adapter plate, which is typically made of resin. The dielectric constant of resin is greater than that of air. Therefore, the presence of the adapter plate increases the capacitance of the chuck to ground, reducing the efficiency of the RF power supply.

[0004] Therefore, how to provide a technical solution for solving the above technical problems is a technical problem that technical personnel in this field urgently need to solve. Summary of the Invention

[0005] This application aims to address at least one of the technical problems existing in the prior art. It proposes a lower electrode assembly that replaces the resin transfer plate and RF column with an RF transmission element and a first circuit transfer plate. The space occupied by the resin transfer plate is filled with air having a low dielectric constant, thereby reducing the chuck's capacitance to ground. Another object of this application is to provide semiconductor processing equipment including the aforementioned lower electrode assembly.

[0006] To achieve the purpose of the present application, a lower electrode device is provided for use in semiconductor process equipment, comprising a chuck, a cable assembly, and a connecting mechanism, wherein the chuck is used to support a wafer; the cable assembly comprises a radio frequency transmission element for transmitting a radio frequency signal and a first cable for transmitting a first alternating current signal;

[0007] The connecting mechanism includes a radio frequency adapter and a first circuit adapter board. The radio frequency adapter is arranged at the bottom of the chuck and is electrically connected to the chuck. A shielding cavity is formed between the radio frequency adapter and the chuck. The radio frequency adapter is used to feed the radio frequency signal output by the radio frequency transmission component into the chuck.

[0008] The first circuit adapter board is located in the shielding cavity and is electrically connected to the RF adapter. A first adapter circuit is provided on the first circuit adapter board. The first adapter circuit is electrically connected to the output end of the first cable and is used to introduce the first AC signal output by the first cable into the first heating element in the chuck.

[0009] In some embodiments, the RF adapter includes an RF adapter plate and a feed connection portion arranged around the RF adapter plate, the feed connection portion is electrically connected to the bottom edge of the chuck, and the shielding cavity is formed between the inner circumference of the feed connection portion, the bottom surface of the chuck and the top surface of the RF adapter.

[0010] In some embodiments, the chuck has at least two main heating zones and a designated zone, each of the main heating zones is correspondingly provided with at least one first heating element, and each of the designated zones in the chuck is correspondingly provided with a second heating element; the cable assembly further includes a second cable for transmitting a second AC signal;

[0011] The connecting mechanism further includes a second circuit adapter board located between the chuck and the first circuit adapter board, wherein a second adapter circuit is provided on the second circuit adapter board, and the second adapter circuit is electrically connected to the first adapter circuit via a connecting structure;

[0012] The first transfer circuit is also electrically connected to the output end of the second cable, and is used to introduce the second AC signal output by the second cable into the second transfer circuit through the connection structure; the second transfer circuit is used to introduce the second AC signal into the second heating element.

[0013] In some embodiments, there are multiple designated areas, and each designated area is correspondingly provided with at least one second heating element;

[0014] The second cable is a multi-core cable, and the number of the designated areas is greater than or equal to the number of core wires in the multi-core cable, and each core wire outputs the second AC signal to at least one second heating element in its corresponding designated area.

[0015] In some embodiments, the connection structure includes a first connector and a first socket that are plugged into each other, a first connector and a conductive connection portion that are electrically connected by affixing, and a second connector for plugging into the chuck;

[0016] The first connector is provided at the ends of the first cable and the second cable, and the first socket is provided on the first circuit adapter board;

[0017] The first connecting piece is arranged on the first circuit adapter plate, and the conductive connecting part is arranged on the second circuit adapter plate;

[0018] The second plug-in piece is arranged on the first circuit adapter plate and used for connecting the first heating element. The first circuit adapter plate is further provided with a connecting conductor used for connecting the first connecting piece and the second plug-in piece to the first socket.

[0019] In some embodiments, the second plug-in piece includes a second input plug-in piece and a second output plug-in piece. Each of the main heating zones corresponds to one of the second input plug-in pieces and one of the second output plug-in pieces. The first cable includes a first input line and a first output line corresponding to the second input plug-in pieces and the second output plug-in pieces respectively. The first input line is electrically connected to the corresponding second input plug-in piece through the connecting conductor. The first output line is electrically connected to the corresponding second output plug-in piece through the connecting conductor.

[0020] In some embodiments, the second circuit adapter plate is provided with a through hole corresponding to the position of the second plug-in piece. The second plug-in piece is connected to the chuck through the through hole.

[0021] In some embodiments, the radio frequency transmission piece is a conductive tube. The radio frequency adapter disc has a via hole penetrating in the thickness direction. The cable assembly is installed in the via hole. The conductive tube and the inner side wall of the via hole are electrically connected through bonding.

[0022] The first cable and the second cable are arranged in the conductive tube. The conductive tube, the first cable and the second cable are electrically insulated by filling the conductive tube with insulating material. The second cable is coaxially arranged with the conductive tube. The first cable is located between the second cable and the conductive tube.

[0023] In some embodiments, the radio frequency adapter disc is provided with a connecting boss arranged around the via hole and located between the via hole and the feed-in connecting part. The radio frequency adapter disc is electrically connected to the first circuit adapter plate through the connecting boss.

[0024] In some embodiments, the cable assembly further includes two adsorption control lines. The chuck is provided with an adsorption electrode used for adsorbing a wafer. The adsorption electrode is connected to the adsorption control plug through the adsorption control plug.

[0025] The conductive tube has a wire hole penetrating through the side wall in the thickness direction. The adsorption control lines are connected to the adsorption control plug through the wire hole.

[0026] The RF adapter plate, the first circuit adapter plate and the second circuit adapter plate are all provided with a clearance hole for making way for the adsorption control plug and insulated from the adsorption control plug, and the adsorption control plug is arranged in the clearance hole.

[0027] In some embodiments, an inner side wall of the through hole is provided with a conductive elastic member for fitting with the conductive tube to ensure electrical conduction between the conductive tube and the RF adapter plate.

[0028] The present application also provides a semiconductor process equipment, including a reaction chamber and any one of the above-mentioned lower electrode devices, wherein the lower electrode device is arranged in the reaction chamber.

[0029] This application has the following beneficial effects:

[0030] The lower electrode device provided in the present application is provided with a connecting mechanism. An RF adapter in the connecting mechanism electrically connects the RF transmission component to the chuck, and the RF is fed into the chuck through the RF transmission component and the RF adapter. A first adapter circuit in the connecting mechanism directs a first AC signal output by a first cable into a first heating element in the chuck, thereby achieving the heating function of the chuck. A shielded cavity is provided between the RF adapter and the chuck, and a first circuit adapter board is disposed in the shielded cavity to prevent interference of the RF on the first circuit adapter board.

[0031] This application eliminates the resin transfer plate between the ceramic insulating plate and the chuck, and instead uses the first circuit transfer plate to support and secure the transfer circuit. The space surrounding the resin transfer plate is filled with air, which has a lower dielectric constant than resin, thereby reducing the chuck's capacitance to ground.

[0032] The present application also provides a semiconductor process equipment including the above-mentioned lower electrode device, and having the above-mentioned advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic structural diagram of a lower electrode device of a lower electrode in a specific embodiment of the present application;

[0034] Figure 2 for Figure 1 a cross-sectional view of the upper portion of the lower electrode assembly of the middle lower electrode;

[0035] Figure 3 for Figure 1 Schematic diagram of a cross section of a cable assembly;

[0036] Figure 4 A schematic diagram of the distribution of the chuck heating area in this application;

[0037] Figure 5 for Figure 1Structure diagram of middle cable assembly, distribution PCB and second circuit adapter connection mode;

[0038] Figure 6 For Figure 1 Schematic diagram of the wiring mode of the distribution PCB;

[0039] Figure 7 Structure diagram of an existing lower electrode device;

[0040] Figure 8 For Figure 7 Schematic diagram of the cross section of the cable.

[0041] Figures 1 to 8 The reference signs in the drawings are:

[0042] Chuck 1, main heating zone 101, designated area 102, ceramic insulating disc 2, groove 21, support boss 22, fixing hole 23, resin fixing piece 24, connection mechanism 3, RF adapter 31, RF adapter disc 311, feed-in connection part 312, connection boss 313, first electrically induced coil 314, second electrically induced coil 315, support table 316, connection sleeve 317, conductive elastic sheet 318, first circuit adapter plate 32, spring thimble 321, bundled plug 322, thimble sleeve 323, copper wire 324, second circuit adapter plate 33, conductive copper sheet 331, cable assembly 4, multi-core cable 401, first cable 402, suction control wire 403, resin fixing block 404, straight section RF connection pipe 405, curved section RF connection pipe 406, straight section shielding sleeve 407, curved section shielding sleeve 408, first insulating support 409, second insulating support 410, third insulating support 411, fourth insulating support 412, connection thimble 413, interface disc 5, base 6, pedestal 7, sealing ring 8;

[0043] Chuck 01, ceramic insulating disc 02, resin adapter disc 03, RF column 04, cable 05, wire 051, RF connection pipe 052. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the technical solutions of the present application, the temperature control device and the reaction chamber using the same provided by the present application will be described in detail below with reference to the drawings.

[0045] Figure 7It is a lower electrode structure in the prior art, with a transfer cavity between the chuck 01 and the ceramic insulating disk 02, and the end of the cable 05 is inserted into the transfer cavity. The outer wall of the cable 05 is the RF connecting tube 052, and the inside of the cable 05 is the wire 051. An RF column 04 is provided in the transfer cavity, and the end of the RF connecting tube 052 is connected to the RF column 04, and the RF is fed into the center of the chuck 01 through the RF column 04. The wire 051 needs to extend from the side wall of the RF column 04 and then be connected to the heating element or adsorption electrode (not shown in the figure) in the chuck 01. In order to fix the wire 051, a resin transfer disk 03 is provided in the transfer cavity. The wire 051 extends from the side wall of the RF column 049 and is routed through the wiring groove inside the resin transfer disk 03. Among them, the end of the DC wire 051 is connected to the adsorption electrode of the chuck 01, which is used to control the adsorption function of the chuck 01; the end of the AC wire 051 is connected to the heating element in the chuck 01, which is used to control the heating of the wafer.

[0046] In the prior art, a resin transfer plate 03 is provided in the transfer cavity for fixing the wire 051 . However, the dielectric constant of the resin material is about three times that of air. Therefore, the presence of the resin transfer plate 03 increases the capacitance of the chuck 01 to the ground, resulting in reduced working efficiency of the RF power supply.

[0047] The lower electrode device provided in this application has a structure as follows Figure 1 As shown, it is applied to semiconductor process equipment. The lower electrode device includes a chuck 1, a cable assembly 4 and a connecting mechanism 3, wherein the chuck 1 is used to carry the wafer; the cable assembly 4 includes a radio frequency transmission element for transmitting radio frequency signals and a first cable 402 for transmitting a first alternating current signal;

[0048] The connecting mechanism 3 includes a radio frequency adapter 31 and a first circuit adapter board 32. The radio frequency adapter 31 is arranged at the bottom of the chuck 1 and is electrically connected to the chuck 1. A shielding cavity is formed between the radio frequency adapter 31 and the chuck 1. The radio frequency adapter 31 is used to feed the radio frequency signal output by the radio frequency transmission component into the chuck 1.

[0049] The first circuit adapter board 32 is located in the shielding cavity and is electrically connected to the RF adapter 31. A first adapter circuit is provided on the first circuit adapter board 32. The first adapter circuit is electrically connected to the output end of the first cable 402 and is used to introduce the first AC signal output by the first cable 402 into the first heating element in the chuck 1. The first adapter circuit can be set according to the distribution method of the first heating element and the first cable 402, which is not limited here.

[0050] In this embodiment, the lower electrode device eliminates the resin adapter plate and instead uses a first circuit adapter plate 32 to introduce the first AC signal output by the first cable 402 into the first heating element in the chuck 1, thereby realizing the heating function of the chuck 1. The RF adapter 31 is electrically connected to the chuck 1, and the RF is fed into the chuck 1 through the RF transmission element and the RF adapter 31 in sequence. A shielding cavity is formed between the RF adapter 31 and the chuck 1, and the first circuit adapter plate 32 is installed in the shielding cavity. The RF is distributed on the outer wall of the shielding cavity, and there is no RF distribution on the inner wall of the shielding cavity. Therefore, the shielding cavity protects the first circuit adapter plate 32 from RF interference. In addition, the first circuit adapter plate 32 is electrically connected to the RF adapter 31, and the two are at the same potential, thereby protecting the first circuit adapter plate 32 from interference caused by the potential change of the RF adapter 31.

[0051] like Figure 1 and Figure 2 As shown, the lower electrode device is provided with a ceramic insulating disk 2 for supporting the chuck 1. The ceramic insulating disk 2 is provided with a groove 21. The connecting mechanism 3 is installed in the groove 21 instead of the resin adapter disk. The bottom of the ceramic insulating disk 2 is provided with a fixing hole 23. The upper end of the cable assembly 4 is inserted into the groove 21 through the fixing hole 23 and is connected to the connecting mechanism 3. The fixing hole 23 and the cable assembly 4 are filled with a resin fixing member 24 to fix the cable assembly 4. An interface disk 5 is also provided below the ceramic insulating disk 2. The lower surface of the chuck 1 and the interface disk 5 can be regarded as a parallel plate capacitor. A cable shield is provided on the outer periphery of the cable assembly 4. The cable shield electrically connects the interface disk 5 to the base 6. The base 6 is grounded, so the capacitance between the chuck 1 and the interface disk 5 can be regarded as the ground capacitance of the chuck 1. The first circuit adapter board 32 and the RF adapter 31 replace the resin adapter disk and are arranged between the ceramic insulating disk 2 and the chuck 1. The sum of the thicknesses of the first circuit adapter plate 32 and the RF adapter 31 is smaller than the thickness of the resin adapter disc, so the space occupied by the original resin adapter disc is mainly filled with air.

[0052] The capacitance of a parallel plate capacitor is calculated as C = εS / (4πkd), where ε is the relative dielectric constant, S is the area between the two capacitor plates, k is the electrostatic force constant, and d is the distance between the two capacitor plates. The formula for calculating series capacitance is 1 / C = 1 / C1 + 1 / C2. Assuming the thickness of the ceramic insulating disk 2 is d1 and the thickness of the resin transfer disk is d2, the reciprocal of the capacitance of the chuck 1 to ground in the solution using the resin transfer disk is:

[0053]

[0054] Among them C 原 is the capacitance of the chuck 1 to the ground in the prior art, ε 陶瓷 is the dielectric constant of the ceramic, ε 树脂 is the dielectric constant of the resin.

[0055] Assuming that the distance between the lower surface of the RF adapter 31 and the ceramic insulating disk 2 is d3, the reciprocal of the ground capacitance of the chuck 1 in the technical solution of this application can be obtained as:

[0056]

[0057] Among them, C 本 is the capacitance of the chuck 1 to the ground in this application, ε 空气 is the dielectric constant of air.

[0058] when When C 本 <C 原 , put equation (1) and equation (2) into After the middle, we can get:

[0059]

[0060] After simplification, we can get:

[0061]

[0062] The dielectric constant of resin is about 3 times that of air. Therefore, it is only necessary to ensure that d3>1 / 3d2;

[0063] The capacitance of the chuck 1 to ground in the technical solution provided by this application is lower than that of the chuck 1 in the prior art. For example, the thickness of the prior art resin adapter plate is 27 mm. However, the present application only needs to ensure that the distance from the lower surface of the RF adapter 31 to the ceramic insulating plate 2 is greater than 9 mm to achieve the purpose of reducing the capacitance of the chuck 1 to ground, thereby improving power supply efficiency.

[0064] Optionally, a support boss 22 can be provided at the bottom of the recess 21 of the ceramic insulating disk 2 to support the RF adapter 31. The RF adapter 31 is fixedly connected to the top of the support boss 22 via a resin screw. The height of the support boss 22 is equal to the distance from the bottom surface of the RF adapter 31 to the ceramic insulating disk 2. By setting the height of the support boss 22 to be greater than one-third of the thickness of the resin adapter disk, the user ensures that the ground capacitance of the chuck 1 in this application is lower than that of the prior art. Of course, the ceramic insulating disk 2 is not limited to this method of supporting the RF adapter 31.

[0065] In some embodiments, as Figure 2 As shown, the RF adapter 31 includes an RF adapter plate 311 and a feeding connection portion 312 arranged around the RF adapter plate 311. The feeding connection portion 312 is electrically connected to the bottom edge of the chuck 1. A shielding cavity is formed between the inner circumference of the feeding connection portion 312, the bottom surface of the chuck 1 and the top surface of the RF adapter 31.

[0066] Optionally, the top of the feed connector 312 contacts the bottom surface of the chuck 1, thereby achieving electrical connection between the two. Furthermore, the RF adapter 31 also includes a first induction coil 314 disposed along the top of the feed connector 312. The first induction coil 314 is located between the feed connector 312 and the bottom surface of the chuck 1, thereby enhancing the electrical conductivity between the feed connector 312 and the chuck 1. RF is guided from the straight RF connector tube 405 to the curved RF connector tube 406, then to the RF adapter 31, and finally enters the edge of the chuck 1 from the edge of the RF adapter 31.

[0067] In some embodiments, the RF adapter plate 311 has a through hole extending through the thickness direction, such as Figure 2 As shown, the RF adapter 31 also includes a connecting sleeve 317 disposed on the bottom surface of the RF adapter plate 311. The inner hole of the connecting sleeve 317 is a via hole that extends upward through the RF adapter plate 311. The cable assembly 4 is installed in the via hole. The RF transmission component is located on the outer wall of the cable assembly 4 and is electrically connected to the inner wall of the connecting sleeve 317. The connecting sleeve 317 increases the contact area between the RF transmission component and the RF adapter 31, enhancing the electrical conductivity between the two.

[0068] Optionally, the inner side wall of the via hole and the radio frequency transmission component are provided with a conductive elastic component. Figure 2 As shown, the RF adapter 31 also includes a mounting slot arranged along the inner sidewall of the via hole and surrounding the axis of the via hole, and the conductive elastic member is a conductive elastic sheet 318. When the cable assembly 4 is installed in the via hole, the conductive elastic sheet 318 is in an elastically compressed state. The inner and outer sides of the conductive elastic sheet 318 respectively squeeze the RF adapter 31 and the RF transmission component, further enhancing the conductive effect between the RF transmission component and the RF adapter 31.

[0069] Optional, such as Figure 2 As shown, the RF adapter 31 also includes a connecting boss 313 surrounding the RF adapter plate 311. The connecting boss 313 is used to support the first circuit adapter board 32. The RF adapter plate 311 is electrically connected to the first circuit adapter board 32 via the connecting boss 313, thereby ensuring that the entire first circuit adapter board 32 and the RF adapter plate 311 are at the same electrical potential. Furthermore, the RF adapter plate 311 is provided with a support platform 316 for supporting the first circuit adapter board 32. The first circuit adapter board 32 and the support platform 316 are securely connected via screws.

[0070] Optional, such as Figure 2As shown, a second inductive coil 315 is further provided between the connecting boss 313 and the first circuit adapter plate 32. The second inductive coil 315 is provided along the top of the connecting boss 313. The second inductive coil 315 can enhance the electrical conductivity between the first circuit adapter plate 32 and the connecting boss 313, thereby ensuring that the first circuit adapter plate 32 and the connecting boss 313 are at the same electrical potential.

[0071] In this embodiment, a first induction coil 314 is disposed between the feed connector 312 and the chuck 1. The first induction coil 314 can enhance the electrical connection between the RF adapter 31 and the chuck 1, thereby reducing RF energy loss. A conductive elastic sheet 318 is disposed between the RF connector and the RF transmission element. The conductive elastic sheet 318 tightly adheres to the RF connector and the RF transmission element through elastic force, thereby ensuring the stability of the electrical connection between the RF connector and the RF transmission element. A second induction coil 315 is disposed between the connection boss 313 of the RF adapter 31 and the first circuit adapter board 32. The second induction coil 315 is disposed around the outer edge of the first circuit adapter board 32, thereby maintaining the same electrical potential throughout the first circuit adapter board 32 and preventing potential changes from affecting the first circuit adapter board 32.

[0072] In the prior art, the chuck 01 is provided with a main heating zone, and the wire 051 in the cable 05 needs to pass through the side wall of the cable 05 and extend into the resin transfer plate 03. The wire 051 is electrically connected to the chuck 01 under the support of the resin transfer plate 03, and the AC signal is introduced into the heating element of the main heating zone. Figure 8 As shown, in the prior art, multiple single wires are usually arranged in the cable 05. The wire 051 needs to extend from the side of the RF column 04 and be connected to the chuck 01. Due to the limitations of the diameter of the cable 05 and the height of the adapter cavity, the number of wires 051 in the cable 05 cannot be increased. Therefore, the prior art can no longer control more heating zones, so that the etching uniformity cannot be improved from the perspective of temperature control. In the present application, the RF adapter 31 is sleeved on the outer periphery of the cable assembly 4, and the output end of the cable assembly 4 is connected to the first circuit adapter board 32. The number of connection points between the cable assembly 4 and the first circuit adapter board 32 is not limited by the depth of the groove 21 in the ceramic insulating disk 2, so that the cable assembly 4 can have more connection points with the chuck 1.

[0073] Optionally, the chuck 1 of the present application is provided with a designated area 102 in addition to the main heating area 101. The designated area 102 in the chuck 1 is provided with a second heating element; the cable assembly 4 further includes a second cable for transmitting a second AC signal;

[0074] The connecting mechanism 3 further includes a second circuit adapter board 33 located between the chuck 1 and the first circuit adapter board 32. A second adapter circuit is provided on the second circuit adapter board 33, and the second adapter circuit is electrically connected to the first adapter circuit via a connecting structure.

[0075] The first switching circuit is also electrically connected to the output end of the second cable, and is used to introduce the second AC signal output by the second cable into the second switching circuit through the connecting structure; the second switching circuit is used to introduce the second AC signal into the second heating element.

[0076] like Figure 2 As shown, the second circuit adapter board 33 can be arranged between the first circuit adapter board 32 and the second circuit adapter board 33, and the second AC signal is introduced into the second heating element through the second cable, the first adapter line, the connecting structure and the second adapter line in sequence. The second heating element can heat the wafer in the designated area 102.

[0077] In some embodiments, there are multiple designated areas 102, and each designated area 102 is provided with at least one second heating element. Figure 4 The specific implementation shown only shows one implementation of the designated area 102. The user can also set the designated area 102 as needed, which is not limited here.

[0078] The second cable is a multi-core cable 401 , and the number of designated areas 102 is greater than or equal to the number of cores in the multi-core cable 401 , and each core outputs a second AC signal to at least one second heating element in its corresponding designated area 102 .

[0079] Optional, such as Figure 3 As shown, multi-core cable 401 includes multiple core wires, each of which can output a second AC signal to at least one second heating element in at least one designated area 102. Of course, a single core wire can also output a second AC signal to multiple second heating elements in a single designated area 102, or to multiple second heating elements in multiple designated areas 102. When a designated area 102 includes more than two second heating elements, the second heating elements can be connected in series or in parallel. When there are more than two designated areas 102, the designated areas 102 can also be connected in series or in parallel.

[0080] In one specific embodiment of the present application, a multi-core cable 401 includes 10 cores. The cores for outputting the second AC signal to the second heating element are called input cores, and the cores for receiving the second AC signal output by the second heating element are called output cores. In this specific embodiment, five cores are input cores, and the remaining five are output cores. There are 25 designated areas 102 arranged in a 5×5 matrix. Each core for outputting the second AC signal controls the second heating element in five designated areas 102, and each core receives the second AC signal output by the second heating element in five designated areas. The second switching circuits are arranged based on the connection between the cores and the second heating elements. Of course, the number of cores in the multi-core cable 401, the number of input and output cores, the number of designated areas 102 in the chuck 1, the distribution of the designated areas 102, and the connection between the designated areas 102 and the cores are not limited to this. Preferably, the number of input cores equals the number of output cores.

[0081] In this embodiment, the second cable is a newly added cable in the cable assembly 4 of the present application, and the designated area 102 is a newly added heating area in the chuck 1 of the present application. The position of the designated area 102 can be set according to the needs of the user. The designated area 102 in the chuck 1 may overlap with the main heating area 101. The first heating element often cannot completely cover the main heating area 101. The second heating element can be set in an area with a lower density of the first heating element. Multiple designated areas 102 are added to the chuck 1 as heating areas, and the heating control of the designated area 102 is achieved by turning the core wire and the power supply on and off, thereby improving the controllability of the wafer heating and thereby improving the uniformity of the wafer heating during the etching process.

[0082] In some embodiments, the RF transmission element is a conductive tube, which is electrically connected to the via via 318 through a conductive elastic sheet. The first cable 402 and the second cable are inserted into the conductive tube, which is filled with an insulating material to electrically insulate the conductive tube, the first cable 402, and the second cable. The second cable and the conductive tube are coaxially arranged, and the first cable 402 is located between the second cable and the conductive tube.

[0083] Optional, such as Figure 3 As shown, there are two or more first cables 402, all of which are distributed along a circle centered on the axis of the second cable. The inner diameter of this circle can be half the sum of the inner diameter of the conductive tube and the circumscribed diameter of all the second cables. Of course, the first cables 402 can also be distributed in other ways, as long as they do not come into contact with the second cables or the conductive tube. The insulating material in the conductive tube can be a resin fixing block 404, although other insulating materials can be selected as needed, without limitation here.

[0084] Optional, such as Figure 1As shown, the sidewall of the base 6 is provided with a mounting hole, the interface plate 5 is located above the base 6, a base 7 is provided below the base 6, the ceramic insulating plate 2 is located above the interface plate 5, and the chuck 1 is disposed on the ceramic insulating plate 2. A cavity is formed between the base 7, the base 6, and the interface plate 5. Sealing rings 8 are provided between the base 7 and the base 6, between the base 6 and the interface plate 5, between the interface plate 5 and the ceramic insulating plate 2, and between the ceramic insulating plate 2 and the chuck 1, thereby sealing the cavity within the base 6. The cable assembly 4 is inserted into the interior of the base 6 through the mounting hole and extends upward to connect to the chuck 1. The cable assembly 4 is sealed between the mounting hole to ensure the sealing of the cavity and prevent the differential pressure between the reaction chamber of the semiconductor process equipment and the base 6 from affecting the lower electrode. The conductive tube is preferably a copper tube. The conductive tube includes a straight RF connecting tube 405 and a curved RF connecting tube 406. The upper part of the curved RF connecting tube 406 is electrically connected to the RF adapter 31. The straight RF connecting tube 405 is fixed in the mounting hole through a first insulating support 409. The first insulating support 409 can also seal the cavity inside the base 6.

[0085] Optional, such as Figure 1 As shown, the cable shield is tubular, with the conductive tube inserted into the cable shield and coaxially arranged with the cable shield. The two ends of the cable shield are electrically connected to the base 6 and the interface board, respectively, forming a shielded space within the cable shield, within which radio frequency is transmitted. The cable shield includes a straight shielding sleeve 407 and a curved shielding sleeve 408. A second insulating support 410 is provided at the end of the straight shielding sleeve 407 near the mounting hole. A third insulating support 411 is provided between the straight shielding sleeve 407 and the curved shielding sleeve 408. A fourth insulating support 412 is provided at the end of the curved shielding sleeve 408 near the ceramic insulating disk 2. The cable shield supports the conductive tube via the second insulating support 410, the third insulating support 411, and the fourth insulating support 412 to prevent contact between the conductive tube and the cable shield. The insulating support can be made of resin material, but users can also choose other materials to make the insulating support, which is not limited here.

[0086] In some embodiments, the connection structure includes a first connector and a first socket that are plugged into each other, a first connector and a conductive connection portion that are electrically connected by fitting, and a second connector for plugging into the chuck 1;

[0087] The ends of the first cable 402 and the second cable are both provided with a first connector, and the first circuit adapter board 32 is provided with a first socket connected to the first connector;

[0088] The first circuit adapter board 32 is further provided with a second connector for connecting to the first heating element and a first connector for connecting to the second circuit adapter board 33. The first circuit adapter board 32 is further provided with a connecting conductor for connecting the first connector and the second connector to the first socket.

[0089] Optional, such as Figure 5 As shown, the first connector is a connecting pin 413, and the first socket is a pin sleeve 323. The ends of the first cable 402 and the second cable are connected to the connecting pin 413 by welding. The pin sleeve 323 is arranged in the first circuit adapter board 32, corresponding to the position of the core wire and the first cable 402. After the connecting pin 413 is inserted into the pin sleeve 323, the multi-core cable 401 and the first cable 402 are electrically connected to the first adapter circuit. Of course, users can also use other methods known in the art to electrically connect the cable assembly 4 to the first adapter circuit, which is not limited here.

[0090] Optional, such as Figure 5 and Figure 6 As shown, the first connector is a spring pin 321, the conductive connecting portion is a conductive copper sheet 331, and the second connector is a cluster plug 322, with a connecting conductor being a copper wire 324. The pin sleeve 323 connected to the core wire is connected to the spring pin 321 via a copper wire 324, while the pin sleeve 323 connected to the first cable 402 is connected to the cluster plug 322 via a copper wire 324. The spring pin 321 on the first circuit adapter board 32 corresponds to the conductive copper sheet 331 on the second circuit adapter board 33. The spring pin 321 and the conductive copper sheet 331 fit together, thereby achieving electrical continuity between the first and second adapter circuits. The second circuit adapter board 33 has a through-hole corresponding to the cluster plug 322, through which the cluster plug 322 connects to the chuck 1. Of course, the connection methods of the first and second adapter circuits, the connection methods of the first adapter circuit and the chuck 1, and the connection methods of the first connector and the second connector to the first socket are not limited to these. Figure 6 Only one of the multiple core wires is shown in the figure. The connection methods of other core wires can be referred to Figure 6 The core wire shown in will not be described again here.

[0091] In some embodiments, the chuck 1 has at least two main heating zones 101 , and each main heating zone 101 is correspondingly provided with at least one first heating element;

[0092] The second connector includes a second input connector and a second output connector. Each main heating zone 101 corresponds to one second input connector and one second output connector. The first cable 402 includes a first input line and a first output line corresponding to the second input connector and the second output connector respectively. The first input line is electrically connected to the corresponding second input connector through a connecting conductor, and the first output line is electrically connected to the corresponding second output connector through a connecting conductor.

[0093] A specific implementation of this application is as follows Figure 4 As shown, the chuck 1 is equipped with four main heating zones 101, comprising a circular area located in the center of the chuck 1 and three annular areas of increasing diameter. Each of the four main heating zones 101 is electrically connected to a first input line and a first output line. The first input line is connected to a cluster plug 322, serving as a second input connector, via a connecting pin 413, a pin sleeve 323, and a copper wire 324. The first output line is connected to a cluster plug 322, serving as a second output connector, via a connecting pin 413, a pin sleeve 323, and a copper wire 324. Of course, the number and distribution of the main heating zones 101 in the chuck 1 are not limited to this.

[0094] In this embodiment, the first circuit adapter board 32 and the second circuit adapter board 33 are electrically connected via spring-loaded pins 321. The compact structure of spring-loaded pins 321 shortens the distance between the first and second circuit adapter boards 32 and 33, thereby increasing the distance between the RF adapter 31 and the ceramic insulating disk 2. The first circuit adapter board 32 is electrically connected to the first heating element in the chuck 1 via a cluster plug 322, thus enabling heating of the primary heating zone 101 in the chuck 1.

[0095] In some embodiments, the chuck 1 is an electrostatic chuck 1 , and the cable assembly 4 further includes two adsorption control wires 403 . The electrostatic chuck 1 is provided with adsorption electrodes for adsorption of wafers. The adsorption control wires 403 are electrically connected to the adsorption electrodes. The adsorption control wires 403 transmit direct current to the adsorption electrodes, which accumulates charge on the adsorption electrodes. The adsorption electrodes then adsorb and secure the wafers using the charge. The structure of the adsorption electrodes can be referenced to the prior art and will not be described in detail here.

[0096] Optionally, the two adsorption control lines 403 are also arranged between the second cable and the conductive tube, and the two adsorption control lines 403 can also be arranged on the circumference where the first cable 402 is located. Figure 3 In the specific embodiment shown, two first cables 402 are provided between the two adsorption control lines 403. Of course, the user can set the distribution method between the adsorption control line 403 and the first cable 402 as needed to avoid the adsorption control line 403 from contacting the first cable 402, the second cable and the conductive tube.

[0097] The voltage of the two adsorption control lines 403 is high, and is not suitable for being connected to the first circuit adapter plate 32 and the second circuit adapter plate 33. In an embodiment of the present application, the outer side wall of the cable assembly 4 has two through holes for wiring, which are located between the radio frequency adapter 31 and the bottom of the ceramic insulating disc 2, and the bottom of the ceramic insulating disc 2 is further provided with two adsorption control plugs. The radio frequency adapter 31, the first circuit adapter plate 32 and the second circuit adapter plate 33 are all provided with accommodation holes for the adsorption control plugs, and the adsorption control plugs are connected to the adsorption electrodes through the accommodation holes. The two adsorption control lines 403 are respectively connected to the corresponding adsorption control plugs through the two through holes for wiring.

[0098] Optionally, the adsorption control plugs can also be the cluster plug 322, which is fixed on the bottom of the ceramic insulating disc 2 by resin. Of course, the selection and fixing mode of the adsorption control plugs are not limited to this.

[0099] In the embodiment, the chuck 1 is an electrostatic chuck 1, and the cable assembly 4 is provided with adsorption control lines 403 for supplying direct current to the adsorption electrodes in the electrostatic chuck 1. The bottom of the ceramic insulating disc 2 is fixedly provided with the cluster plug 322, which is connected to the electrostatic chuck 1 through the radio frequency adapter 31, the first circuit adapter plate 32 and the second circuit adapter plate 33. The radio frequency adapter 31, the first circuit adapter plate 32 and the second circuit adapter plate 33 are all provided with accommodation holes for the cluster plug 322 to pass through, so as to avoid contact with the cluster plug 322. The adsorption control lines 403 are connected to the lower end of the cluster plug 322 through the through holes for wiring in the outer side wall of the cable assembly 4, so as to supply direct current to the electrostatic chuck 1.

[0100] The present application also provides a semiconductor process equipment, which comprises a reaction chamber and the lower electrode device of any one of the above embodiments, and the lower electrode device is arranged in the reaction chamber. The structures of other parts of the semiconductor process equipment can refer to the prior art, and will not be described here.

[0101] It can be understood that the above embodiments are only exemplary embodiments for illustrating the principles of the present application, and the present application is not limited thereto. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and essence of the present application, and these modifications and improvements are also regarded as the protection scope of the present application.

Claims

1. A lower electrode device, used in semiconductor process equipment, characterized in that: The invention comprises a chuck, a cable assembly and a connecting mechanism, wherein the chuck is used to carry a wafer; the cable assembly comprises a radio frequency transmission element for transmitting a radio frequency signal and a first cable for transmitting a first alternating current signal; The connecting mechanism includes a radio frequency adapter and a first circuit adapter board. The radio frequency adapter is arranged at the bottom of the chuck and is electrically connected to the chuck. A shielding cavity is formed between the radio frequency adapter and the chuck. The radio frequency adapter is used to feed the radio frequency signal output by the radio frequency transmission component into the chuck. The first circuit adapter board is located in the shielding cavity and is electrically connected to the RF adapter. A first adapter circuit is provided on the first circuit adapter board. The first adapter circuit is electrically connected to the output end of the first cable and is used to introduce the first AC signal output by the first cable into the first heating element in the chuck.

2. The lower electrode device according to claim 1, characterized in that The RF adapter includes a RF adapter plate and a feed connection portion arranged around the RF adapter plate, the feed connection portion is electrically connected to the bottom edge of the chuck, and the shielding cavity is formed between the inner circumference of the feed connection portion, the bottom surface of the chuck and the top surface of the RF adapter.

3. The lower electrode device according to claim 2, characterized in that: The chuck has at least two main heating zones and a designated zone, each of the main heating zones is correspondingly provided with at least one first heating element, and the designated zone in the chuck is correspondingly provided with a second heating element; the cable assembly further includes a second cable for transmitting a second AC signal; The connecting mechanism further includes a second circuit adapter board located between the chuck and the first circuit adapter board, wherein a second adapter circuit is provided on the second circuit adapter board, and the second adapter circuit is electrically connected to the first adapter circuit via a connecting structure; The first transfer circuit is also electrically connected to the output end of the second cable, and is used to introduce the second AC signal output by the second cable into the second transfer circuit through the connection structure; The second switching circuit is used to introduce the second AC signal into the second heating element.

4. The lower electrode device according to claim 3, characterized in that: There are multiple designated areas, and each designated area is correspondingly provided with at least one second heating element; The second cable is a multi-core cable, and the number of the designated areas is greater than or equal to the number of cores in the multi-core cable, and each core outputs the second AC signal to at least one second heating element in its corresponding designated area.

5. The lower electrode device according to claim 3, characterized in that: The connection structure includes a first connector and a first socket that are plugged into each other, a first connector and a conductive connecting portion that are electrically connected by fitting together, and a second connector for plugging into the chuck; The first connector is provided at the ends of the first cable and the second cable, and the first socket is provided on the first circuit adapter board; The first connecting member is provided on the first circuit adapter board, and the conductive connecting portion is provided on the second circuit adapter board; The second connector is provided on the first circuit adapter board for connecting to the first heating element. The first circuit adapter board is also provided with a connecting conductor for connecting the first connector and the second connector to the first socket.

6. The lower electrode device according to claim 5, characterized in that: The second connector includes a second input connector and a second output connector, each main heating zone corresponds to one second input connector and one second output connector, the first cable includes a first input line and a first output line corresponding to the second input connector and the second output connector respectively, the first input line is electrically connected to the corresponding second input connector through the connecting conductor, and the first output line is electrically connected to the corresponding second output connector through the connecting conductor.

7. The lower electrode device according to claim 5, characterized in that: The second circuit adapter board is provided with a through hole corresponding to the position of the second plug-in connector, and the second plug-in connector passes through the through hole and is connected to the chuck.

8. The lower electrode device according to any one of claims 3 to 7, characterized in that: The RF transmission component is a conductive tube, the RF adapter plate has a through hole extending through the through hole in the thickness direction, the cable assembly is installed in the through hole, and the conductive tube and the inner side wall of the through hole are electrically connected by bonding; The first cable and the second cable are passed through the conductive tube, and the conductive tube is filled with insulating material for electrically insulating the conductive tube, the first cable, and the second cable; wherein the second cable is coaxially arranged with the conductive tube; and the first cable is located between the second cable and the conductive tube.

9. The lower electrode device according to claim 8, characterized in that: The RF adapter plate is provided with a connection boss which is arranged around the via hole and is located between the via hole and the feed connection portion. The RF adapter plate is electrically connected to the first circuit adapter board via the connection boss.

10. The lower electrode device according to claim 8, characterized in that: The cable assembly further comprises two adsorption control lines, the chuck is provided with an adsorption electrode for adsorbing the wafer, and the adsorption electrode is connected to the adsorption electrode via an adsorption control plug; The conductive tube has a wiring hole penetrating through its side wall along the thickness direction, and the adsorption control line passes through the wiring hole and is connected to the adsorption control plug; The RF adapter plate, the first circuit adapter plate and the second circuit adapter plate are all provided with a clearance hole for making way for the adsorption control plug and insulated from the adsorption control plug, and the adsorption control plug is arranged in the clearance hole.

11. The lower electrode device according to claim 9, characterized in that: The inner side wall of the through hole is provided with a conductive elastic member for fitting with the conductive tube to ensure electrical conduction between the conductive tube and the radio frequency adapter plate.

12. A semiconductor process equipment comprising a reaction chamber, characterized in that: It also includes the lower electrode device according to any one of claims 1 to 11, wherein the lower electrode device is arranged in the reaction chamber.

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