Electrostatic chuck and semiconductor processing apparatus

Abstract

The application provides an electrostatic chuck and a semiconductor process equipment, the electrostatic chuck comprises a chuck body, and an adsorption electrode, a heating element, a first electrode terminal and a second electrode terminal arranged in the chuck body, wherein a first end of the first electrode terminal is electrically connected with the adsorption electrode, and a second end of the first electrode terminal is used for being electrically connected with an adsorption power supply and a radio frequency source; a first end of the second electrode terminal is used for being electrically connected with the heating element, and a second end of the second electrode terminal is used for being electrically connected with an alternating current power supply; a first filter circuit is connected between the first end of the second electrode terminal and the heating element or between the second end of the second electrode terminal and the alternating current power supply, and the first filter circuit is used for filtering radio frequency current on the heating element. The application can filter the radio frequency current on the heating element, so that the risk of sparking on the cable and pipeline structure can be effectively reduced, and the interference of the radio frequency on the matching device can also be reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and more specifically, to an electrostatic chuck and semiconductor process equipment. Background Technology

[0002] In the semiconductor industry, electrostatic chucks are one of the primary methods for holding wafers in vacuum chambers. Compared to other wafer-fixing structures, electrostatic chucks also offer heating, temperature control, and RF power loading capabilities. Due to their excellent stability, low particle count, and superior temperature control, electrostatic chucks are finding increasingly widespread application in the semiconductor field.

[0003] An existing electrostatic chuck structure is as follows: Figure 1 As shown, the electrostatic chuck includes a chuck body 11 and an adsorption electrode 12 and a heating element 13 (e.g., a heating wire, which can be wound into a planar spiral structure) disposed within the chuck body 11. The upper surface of the chuck body 11 has multiple protrusions 111 for supporting the wafer. The adsorption electrode 12 is electrically connected to a DC power supply and an RF source (not shown) via adsorption electrode terminals 121. The DC power supply applies a DC voltage to the adsorption electrode 12 to generate an electrostatic adsorption force between the adsorption electrode 12 and the wafer, thereby achieving wafer adsorption and fixation. The RF source applies RF power to the adsorption electrode 12 to provide RF power to the chamber via capacitive coupling. The heating element 13 is electrically connected to an AC power supply (not shown) via heating terminals 131. The AC power supply provides heating power to the heating element 13 to achieve temperature control of the wafer.

[0004] However, when the RF source applies RF power to the adsorption electrode 12, a portion of the RF current couples to the heating element 13. This RF current interferes with the heating function of the heating element 13 and may also damage the machine. However, existing filtering circuits cannot filter out the RF current on the heating element 13. This RF current not only couples to other cables and pipes in the bellows below the chuck body, causing arcing between cables and pipes, but may also cause changes in the matching position of the matching device, leading to interference with the process results and impedance mismatch in different chambers. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes an electrostatic chuck and semiconductor process equipment, which can filter out the radio frequency current on the heating element, thereby effectively reducing the risk of arcing in cable and pipe structures, and also reducing the interference of radio frequency on the matching unit, thereby ensuring that the process results are not affected and improving the consistency of the matching state of different chambers.

[0006] To achieve the purpose of this invention, an electrostatic chuck is provided for use in semiconductor equipment. The electrostatic chuck includes a chuck body, characterized in that it further includes an adsorption electrode, a heating element, a first electrode terminal, and a second electrode terminal disposed in the chuck body, wherein a first end of the first electrode terminal is electrically connected to the adsorption electrode, and a second end of the first electrode terminal is used to be electrically connected to an adsorption power supply and a radio frequency source.

[0007] The first end of the second electrode terminal is used to be electrically connected to the heating element, and the second end of the second electrode terminal is used to be electrically connected to the AC power supply; a first filter circuit is connected between the first end of the second electrode terminal and the heating element or between the second end of the second electrode terminal and the AC power supply, and the first filter circuit is used to filter out the radio frequency current on the heating element.

[0008] Optionally, the first filter circuit includes a first inductor and a first capacitor, wherein,

[0009] The first inductor is connected in series between the first end of the second electrode terminal and the heating element or between the second end of the second electrode terminal and the AC power supply.

[0010] The first electrode of the first capacitor is connected in parallel with the first inductor, and the second electrode of the first capacitor is grounded.

[0011] Optionally, the first inductor is connected in series between the second end of the second electrode terminal and the AC power supply;

[0012] The electrostatic chuck further includes a hollow outer conductor and an inner conductor passing through the outer conductor. An insulating medium is provided between the outer conductor and the inner conductor to electrically insulate them. The outer conductor and the inner conductor serve as the second electrode and the first electrode of the first capacitor, respectively. Both ends of the inner conductor are electrically connected to the second end of the second electrode terminal and the AC power supply. A portion of the inner conductor near the second electrode terminal is wound to form the first inductor.

[0013] Optionally, the first electrode and the second electrode of the first inductor and the first capacitor are both disposed in the chuck body; wherein, the first inductor is formed by winding wire, and the first end of the first inductor is electrically connected to the heating element by welding, and the second end of the first inductor is electrically connected to the first end of the second electrode terminal by welding.

[0014] The first electrode of the first capacitor is electrically connected to the second end of the first inductor by welding. The second electrode of the first capacitor is disposed opposite to the first electrode of the first capacitor in the axial direction of the chuck body. The second electrode of the first capacitor is electrically connected to the grounding flange disposed on the side of the chuck body away from its bearing surface by welding.

[0015] Optionally, the first inductor is connected in series between the first end of the second electrode terminal and the heating element;

[0016] The chuck body includes a first body layer and a second body layer stacked together. The first body layer has a second electrode terminal extending through its thickness direction. A grounding flange, a first connecting line, and a first electrode of the first capacitor are disposed on a first surface of the first body layer opposite to the second body layer. The first electrode is electrically connected to the grounding flange via the first connecting line. On the second surface of the first body layer opposite to the second body layer, a second connecting line, a second electrode of the first capacitor, and a first coil layer of the first inductor are disposed. The second electrode is electrically connected to the second electrode terminal via the second connecting line. One end of the first coil layer is electrically connected to the second electrode, and the other end of the first coil layer has a first connecting post extending through the second body layer along its thickness direction.

[0017] A second coil layer containing the heating element and the first inductor is disposed on a third surface of the second main body layer opposite to the first main body layer. One end of the second coil layer is electrically connected to the first connecting post, and the other end of the second coil layer is electrically connected to the heating element.

[0018] Optionally, the second main body layer may be multi-layered;

[0019] In the multi-layer second main body layer, except for the second main body layer furthest from the first main body layer, the other end of the second coil layer on all the second main body layers is provided with a second connecting post. The second connecting post penetrates through the adjacent second main body layer along the thickness direction of the second main body layer. The second coil layers on each of the two adjacent second main body layers are electrically connected through the second connecting post.

[0020] One end of the second coil layer on the second main body layer closest to the first main body layer is electrically connected to the first connecting post; the other end of the second coil layer on the second main body layer furthest from the first main body layer is electrically connected to the heating element.

[0021] Optionally, the first connecting line, the first electrode of the first capacitor, the second connecting line, the second electrode of the first capacitor, the first coil layer and the second coil layer of the first inductor, and the heating element are all made by screen printing.

[0022] Optionally, the second main body layer is made using a casting method.

[0023] Optionally, the first end of the second electrode terminal is connected to the heating element via the first filter circuit, and the second end of the second electrode terminal is connected to the AC power supply via the second filter circuit; or, the second end of the second electrode terminal is connected to the AC power supply via the first filter circuit, and the first filter circuit is connected to the AC power supply via the second filter circuit.

[0024] The second filter circuit is used to filter out the radio frequency current in the circuit between the second electrode terminal and the AC power supply.

[0025] Optionally, the second filter circuit includes a second inductor and a second capacitor, with the second inductor connected in series between the AC power supply and the second terminal of the second electrode; the first electrode of the second capacitor is electrically connected to the second inductor, and the second electrode of the second capacitor is grounded.

[0026] Optionally, the electrostatic chuck further includes a bias detection structure and a detection terminal disposed in the chuck body, wherein the detection end of the bias detection structure extends to the bearing surface of the chuck body, the other end of the bias detection structure away from the detection end is electrically connected to the first end of the detection terminal, and the second end of the detection terminal is used for electrical connection with the processing circuit.

[0027] The first filter circuit is connected between the first end of the detection terminal and the bias detection structure or between the second end of the second electrode terminal and the processing circuit. The first filter circuit is used to filter out the radio frequency current on the bias detection structure.

[0028] As another technical solution, the present invention also provides a semiconductor process apparatus, including a process chamber and an electrostatic chuck disposed in the process chamber, characterized in that the electrostatic chuck is the electrostatic chuck provided by the present invention.

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

[0030] The electrostatic chuck provided by the present invention has a first filter circuit connected between the first end of the second electrode terminal electrically connected to the heating element and the heating element or between the second end of the second electrode terminal and the AC power supply. This circuit can filter out the radio frequency current on the heating element, thereby effectively reducing the risk of arcing in cables and pipe structures. It can also reduce the interference of radio frequency to the matching unit, thereby ensuring that the process results are not affected and improving the consistency of the matching state of different chambers.

[0031] The semiconductor process equipment provided by this invention, by employing the electrostatic chuck provided by this invention, can effectively reduce the risk of arcing in cable and pipe structures, and can also reduce radio frequency interference to the matching unit, thereby ensuring that the process results are not affected and improving the consistency of the matching state of different chambers. Attached Figure Description

[0032] Figure 1 Here is a structural diagram of an existing electrostatic chuck;

[0033] Figure 2 This is a structural diagram of a semiconductor process apparatus provided in a comparative embodiment of the present invention;

[0034] Figure 3 A structural diagram of a semiconductor process apparatus provided in another comparative embodiment of the present invention;

[0035] Figure 4 A cross-sectional view of the electrostatic chuck provided in the first embodiment of the present invention;

[0036] Figure 5 Another cross-sectional view of the electrostatic chuck provided in the first embodiment of the present invention;

[0037] Figure 6 for Figure 4 Top perspective view of the electrostatic chuck;

[0038] Figure 7A This is a top view of the first surface of the first main body layer used in the first embodiment of the present invention;

[0039] Figure 7B This is a top view of the second surface of the first main body layer used in the first embodiment of the present invention;

[0040] Figure 7C This is another top view of the second surface of the first main body layer used in the first embodiment of the present invention;

[0041] Figure 7D This is a top view of the third surface of the second main body layer used in the first embodiment of the present invention;

[0042] Figure 7EThis is another top view of the third surface of the second main body layer used in the first embodiment of the present invention;

[0043] Figure 8 A cross-sectional view of an electrostatic chuck provided in the second embodiment of the present invention;

[0044] Figure 9 Another cross-sectional view of the electrostatic chuck provided in the second embodiment of the present invention;

[0045] Figure 10 This is a structural diagram of a semiconductor process equipment provided in the third embodiment of the present invention. Detailed Implementation

[0046] To enable those skilled in the art to better understand the technical solutions of the present invention, the electrostatic chuck and semiconductor process equipment provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0047] Please see Figure 2 As a comparative embodiment of this example, a semiconductor process apparatus includes a process chamber 21, in which an electrostatic chuck is disposed for adsorbing and fixing wafers. Specifically, the electrostatic chuck includes a chuck body 11 and adsorption electrodes 12 and heating elements 13 (e.g., heating wires) disposed in the chuck body 11. The upper surface of the chuck body 11 has a plurality of protrusions 111 distributed thereon for supporting wafers. The bottom of the chuck body 11 is provided with a bellows 22, which is used to seal with the chamber when the chuck body 11 moves up and down.

[0048] The adsorption electrode 12 is electrically connected to the DC power supply 24 via the adsorption electrode terminal 121, and to the RF power supply 23 via the matching adapter 25. The DC power supply 24 applies a DC voltage to the adsorption electrode 12 to generate an electrostatic adsorption force between the adsorption electrode 12 and the wafer, thereby achieving the adsorption and fixation of the wafer. The RF power supply 23 applies RF power to the adsorption electrode 12 to provide RF power to the chamber via capacitive coupling. Additionally, a DC blocking capacitor 26 is provided between the matching adapter 25 and the DC power supply 24, which serves to block DC and pass AC signals.

[0049] Heating element 13 is electrically connected to AC power supply 27 via heating terminal 131. AC power supply 27 provides heating power to heating element 13 to achieve temperature control of the wafer. However, when RF power supply 23 applies RF power to adsorption electrode 12, a portion of RF current is coupled to heating element 13. This RF current interferes with the heating function of heating element 13 and may also damage the equipment. To address this, a second filter circuit 28 is provided in the circuit between heating terminal 131 and AC power supply 27. This second filter circuit 28 is located outside process chamber 21 and is used to filter out the RF current in the circuit connected between AC power supply 27 and heating element 13. However, this second filter circuit 28 cannot filter out the RF current on heating element 13. This RF current not only couples to other cables and pipes in the bellows below the chuck body, causing arcing between cables and pipes, but may also cause changes in the matching position of matching device 25, resulting in interference with process results and impedance mismatch between different chambers.

[0050] As another comparative embodiment of this example, such as Figure 3 As shown, based on the above comparative embodiment, this comparative embodiment adds a bias detection structure 31 and a detection terminal 311 disposed in the chuck body 11. The detection end of the bias detection structure 31 extends to the bearing surface of the chuck body 11. For example, the bias detection structure 31 is a conductive bump disposed on the upper surface of the chuck body 11. This conductive bump serves as a detection terminal, capable of detecting the plasma bias voltage during plasma ignition. This bias voltage is led out of the chuck body 11 through the detection terminal 311 and transmitted to the processing circuit 33 via wires for reading, recording, displaying, and other processing of the bias voltage. Similar to the heating element 13 described above, when the RF power supply 23 applies RF power to the adsorption electrode 12, a portion of the RF current will couple to the bias detection structure 31. This portion of the RF current will interfere with the detection function of the bias detection structure 31 and may also damage the machine. Therefore, a third filter circuit 32 is provided on the circuit between the probe terminal 311 and the processing circuit 33. The third filter circuit 32 is located outside the process chamber 21 and is used to filter out the radio frequency current in the circuit connected between the probe terminal 311 and the processing circuit 33. However, the third filter circuit 32 cannot filter out the radio frequency current on the bias probe structure 31. This part of the radio frequency current will not only couple to other cables and pipe structures in the bellows located below the chuck body, causing arcing between cables and pipes, but may also cause the matching position of the matching device 25 to change, resulting in interference with the process results and mismatch in impedance states of different chambers.

[0051] First Embodiment

[0052] To resolve at least one of the above issues, please refer to Figure 4 The first embodiment of the present invention provides an electrostatic chuck applied to semiconductor equipment. The electrostatic chuck includes a chuck body 41, and adsorption electrodes 42, heating elements 43, first electrode terminals 421, and second electrode terminals 431 disposed within the chuck body 41. The chuck body 41 is, for example, made of ceramic material. The first end of the first electrode terminal 421 is electrically connected to the adsorption electrode 42, and the second end of the first electrode terminal 421 is used for electrical connection to an adsorption power supply and a radio frequency source. Specifically, there are, for example, two adsorption electrodes 42, whose orthographic projections on the upper surface of the chuck body 41 form, for example, a double "D" shape, or an inner and outer nested shape. Of course, other arbitrary shapes can also be used, and the embodiments of the present invention do not have any particular limitations in this regard. There are also two first electrode terminals 421, and their first ends are respectively electrically connected to the two adsorption electrodes 42. The second ends of the two first electrode terminals 421 are electrically connected to the adsorption power supply and the radio frequency source, with the specific connection method being the same as described above. Figure 2 The adsorption electrode terminal 121 shown is electrically connected to the DC power supply 24 and to the RF power supply 23 via the matching adapter 25 in the same way. Optionally, the second ends of the two first electrode terminals 421 are electrically connected to the adsorption power supply and the RF power supply via a first circuit, which is the... Figure 2 The circuit located between the adsorption electrode terminal 121 and the DC power supply 24 and matching unit 25 will not be described in detail here. In practical applications, the adsorption electrode 42 can be one or any other arbitrary number, and the present invention does not impose any particular limitation on this.

[0053] The first end of the second electrode terminal 431 is used for electrical connection with the heating element 43, and the second end of the second electrode terminal 431 is used for electrical connection with the AC power supply. Specifically, there are two second electrode terminals 431, and the first ends of the two terminals are respectively electrically connected to the two ends of the heating element 43, and the second ends of the two terminals are respectively electrically connected to the two poles of the AC power supply. The heating element 43 is, for example, a heating wire, which can be wound around the circumference of the chuck body 11 at least once, for example, wound to form a planar helical structure. Of course, the heating element 43 can also adopt other arbitrary structures, and the embodiments of the present invention do not have any particular limitations in this regard.

[0054] Furthermore, a first filter circuit 51 is connected between the first end of each second electrode terminal 431 and the heating element 43. This first filter circuit 51 is used to filter out the radio frequency current on the heating element 43. This is because the first filter circuit 51 located between the first end of each second electrode terminal 431 and the heating element 43 can reduce or even prevent the radio frequency current on the heating element 43 from coupling to other cables and pipe structures in the bellows located below the chuck body 41, thus filtering out the radio frequency current on the heating element 43. In this way, the risk of arcing on the cables and pipe structures can be effectively reduced, and the interference of radio frequency to the matching unit can also be reduced, thereby ensuring that the process results are not affected and improving the consistency of the matching state of different chambers.

[0055] In some optional embodiments, the first filter circuit 51 includes a first inductor 511 and a first capacitor 512. The first inductor 511 is connected in series between the first end of the second electrode terminal 431 and the heating element 43. The first electrode of the first capacitor 512 is connected in parallel with the first inductor 511, and the second electrode of the first capacitor 512 is grounded. When the RF power supply applies RF power to the adsorption electrode 42, a portion of the RF current is applied to the heating element 43 through capacitive coupling. This portion of the RF current loses some energy when passing through the first inductor 511 connected in series between the first end of the second electrode terminal 431 and the heating element 43, and flows back to ground potential from the grounded second electrode when passing through the parallel-connected first capacitor 512, thereby filtering out the RF current on the heating element 43.

[0056] In some alternative embodiments, such as Figure 5 As shown, the electrostatic chuck also includes a bias detection structure 61 and a detection terminal 611 in the chuck body 41. The detection end of the bias detection structure 61 extends to the bearing surface of the chuck body 41. For example, the bias detection structure 61 is a conductive bump on the upper surface of the chuck body 41, which serves as a detection terminal to detect the bias voltage of the plasma during plasma ignition. The other end of the bias detection structure 61 away from the detection end is electrically connected to the first end of the detection terminal 611, and the second end of the detection terminal 611 is used to be electrically connected to the processing circuit. In this way, the bias voltage detected by the bias detection structure 61 is transmitted to the processing circuit through the detection terminal 611 and the wire for reading, recording, displaying, and other processing of the bias voltage.

[0057] Furthermore, a first filter circuit 51' is connected between the first end of the probe terminal 611 and the bias probe structure 61 to filter out the radio frequency current on the bias probe structure 61. The structure and filtering principle of the first filter circuit 51' are the same as those of the first filter circuit 51 described above, and will not be repeated here.

[0058] In some optional embodiments, the first filter circuit 51' includes a first inductor 511' and a first capacitor 512'. The first inductor 511' is connected in series between the first end of the probe terminal 611 and the bias probe structure 61; the first electrode of the first capacitor 512' is connected in parallel with the first inductor 511', and the second electrode of the first capacitor 512' is grounded. When the RF power supply applies RF power to the adsorption electrode 42, a portion of the RF current is applied to the bias probe structure 61 through capacitive coupling. This portion of the RF current loses some energy when passing through the first inductor 511' connected in series between the first end of the probe terminal 611 and the bias probe structure 61, and flows back to ground potential from the grounded second electrode when passing through the parallel first capacitor 512', thereby filtering out the RF current on the bias probe structure 61.

[0059] The specific structure of each of the first filter circuits 51 and 51' can be varied. Taking the first filter circuit 51, which includes a first inductor 511 and a first capacitor 512, as an example... Figure 6 As shown ( Figure 6 Only the structure of the first filter circuit 51 and heating element 43 in the chuck body 41 is shown. The first electrode and the second electrode of the first inductor 511 and the first capacitor 512 are both disposed in the chuck body 11. The first inductor 511 is made of metal wire, and the first end of the first inductor 511 is electrically connected to one end of the heating element 43, for example, through a connecting wire 432, which can be done by welding. The second end of the first inductor 511 is electrically connected to the first end of the second electrode terminal 431, for example, through welding. The first electrode and the second electrode of the first capacitor 512 are both electrode plates, for example. The first electrode is electrically connected to the second end of the first inductor 511, for example, through a connecting wire, which can be done by welding, thus realizing the parallel connection of the first electrode and the first inductor 511. The second electrode is axially opposite to the first electrode in the chuck body 11, and is electrically connected, for example, via a connecting wire to a grounding flange 71 located on the side of the chuck body 41 opposite to its bearing surface (i.e., the lower side), for grounding via the grounding flange 71. The electrical connection can also be welding. In practical applications, the grounding flange 71 can be connected via a bellows (e.g., Figure 2 The bellows 22 shown is electrically connected to the grounded bottom wall of the process chamber.

[0060] In some optional embodiments, the first filter circuit 51 and the connecting wires described above can be pre-embedded in the slurry of the chuck body 41 before the sintering process of the chuck body 41, and then sintered together with the chuck body 41 to complete the fabrication. Optionally, the material filling the chuck body 41 between the first electrode and the second electrode of the first capacitor 512 can be used as the dielectric layer of the first capacitor 512, and the capacitance value of the first capacitor 512 can be set by adjusting the thickness of the dielectric layer.

[0061] The specific structure of each of the first filter circuits 51 and 51' described above can also adopt another structure. Taking the first filter circuit 51, which includes a first inductor 511 and a first capacitor 512, as an example, Figures 7A to 7E As shown ( Figures 7A to 7E Only the structure of the first filter circuit 51, heating element 43, etc. in the chuck body 41 is shown, such as Figure 7E As shown, the chuck body 41 includes a first body layer 41a and a second body layer 41b stacked on top of the first body layer 41a, and the outer diameter of the second body layer 41b can be, for example, smaller than the outer diameter of the first body layer 41a. Of course, in practical applications, the outer diameter of the second body layer 41b can also be equal to the outer diameter of the first body layer 41a.

[0062] Among them, such as Figure 7A As shown, a second electrode terminal 431 is provided on the first main body layer 41a, extending through its thickness direction. A first electrode 512a, a grounding flange 71, a first connecting line 513, and a first capacitor 512a are provided on the first surface 412 of the first main body layer 41a away from the second main body layer 41b (i.e., the lower surface of the first main body layer 41a). The first electrode 512a is electrically connected to the grounding flange 71 through the first connecting line 513, so that the first electrode 512a can be grounded through the grounding flange 71.

[0063] Figure 7B This is a top view of the second surface 413 (i.e., the upper surface of the first main body layer 41a) opposite the second main body layer 41b during the fabrication process of the first filter circuit 51 (before the step of fabricating the first connecting post), as shown below. Figure 7B As shown, a second connecting line 432, a second electrode 512b of a first capacitor 512, and a first coil layer 511a of a first inductor 511 are provided on the second surface 413. The second electrode 512b is electrically connected to the second electrode terminal 431 through the second connecting line 432; one end of the first coil layer 511a is electrically connected to the second electrode 512b.

[0064] like Figure 7CAs shown, a first connecting post 511b is provided at the other end of the first coil layer 511a, and the first connecting post 511b penetrates the second main body layer 41b along the thickness direction of the second main body layer 41b. Figure 7D This is a top view of the second main body layer 41b facing away from the third surface 414 (i.e., the upper surface of the second main body layer 41b) during the fabrication process of the first filter circuit 51 (before the step of fabricating the second coil layer of the first inductor), as shown below. Figure 7D As shown, the upper end of the first connecting post 511b, away from the first coil layer 511a, is located on the aforementioned third surface 414. Furthermore, as... Figure 7E As shown, a heating element 43 and a second coil layer 511c of a first inductor 511 are provided on the third surface 414. One end of the second coil layer 511c is electrically connected to the first connecting post 511b, and the other end of the second coil layer 511c is electrically connected to one end of the heating element 43.

[0065] The aforementioned chuck body 41 is a multi-layer structure composed of two main body layers. In the aforementioned first filter circuit 51, the first inductor 511 is a multi-layer structure composed of two coil layers connected in series via a vertically penetrating connecting post through the main body layer. The aforementioned first capacitor 512 is a multi-layer structure composed of two electrode plates, electrically connected to corresponding components via connecting wires. This multi-layer structure combination is suitable for manufacturing using screen printing. This manufacturing method is simple, efficient, and low-cost, making it suitable for mass production. Optionally, the aforementioned first connecting wire 513, the first electrode 512a of the first capacitor 512, the second connecting wire 432, the second electrode 512b of the first capacitor 512, the first coil layer 511a and the second coil layer 511c of the first inductor 511, and the heating element 43 can all be manufactured using screen printing.

[0066] It should be noted that in the above embodiment, the second main body layer 41b is a single layer, and the first inductor 511 is a multi-layer structure composed of two coil layers. However, the embodiments of the present invention are not limited to this. In practical applications, if it is necessary to increase the number of coil layers of the first inductor 511 (i.e., increase the number of turns of the first inductor 511), it can be achieved by increasing the number of layers of the second main body layer 41b and setting a coil layer and a connecting post on each of the added second main body layers 41b. Specifically, when the second main body layer 41b is multi-layered, except for the second main body layer 41b furthest from the first main body layer 41a (i.e., the uppermost second main body layer 41b), the other end of the second coil layer 511c on all the second main body layers 41b is provided with a second connecting post. The second connecting post penetrates through another adjacent second main body layer 41b (i.e., the uppermost second main body layer 41b) along the thickness direction of the second main body layer 41b; the second coil layers 511c on each of the two adjacent second main body layers 41b are electrically connected through the second connecting post. One end of the second coil layer 511c on the second main body layer 41b closest to the first main body layer 41a (i.e., the lowest second main body layer 41b) is electrically connected to the first connecting post 511b; the other end of the second coil layer 511c on the second main body layer 41b furthest from the first main body layer 41a (i.e., the highest second main body layer 41b) is electrically connected to the heating element 43. Thus, the chuck body 41 is a multi-layer structure composed of three or more main body layers, and in the first filter circuit 51, the first inductor 511 is a multi-layer structure composed of three or more coil layers, with adjacent coil layers connected in series through a connecting post (first connecting post or second connecting post) that vertically penetrates the main body layer.

[0067] In some optional embodiments, the second main body layer 41b can be made by casting to realize that multiple second main body layers 41b are connected as one unit, and the second main body layer 41b is connected to the first main body layer 41a.

[0068] In some alternative embodiments, the first filter circuit 51' described above may also employ the multilayer structure described above and be fabricated using screen printing.

[0069] In some optional embodiments, based on the above-described multilayer structure combination, the inductance value of the first inductor 511 can be controlled by controlling the perimeter of the coil layers of the first inductor 511, the vertical spacing between two adjacent coil layers, and the number of coil layers. Specifically, the number of turns of the first inductor 511 and the vertical spacing between two adjacent coil layers can be controlled by controlling the thickness of the second main body layer 41b and the number of second main body layers 41b between two adjacent coil layers. The number of turns of the first inductor 511 (i.e., the number of coil layers) is, for example, greater than or equal to 2 layers and less than or equal to 30 layers. Furthermore, the capacitance value of the first capacitor 512 can be controlled by controlling the relative area of ​​the two electrode plates of the first capacitor 512 and the spacing between the two electrode plates (i.e., the thickness of the first main body layer 41a).

[0070] In some optional embodiments, in addition to the first filter circuit 51 described above, to prevent further radio frequency signal interference, a second filter circuit is connected between the second end of the second electrode terminal 431 and the AC power supply to filter out the radio frequency current in the circuit between the second electrode terminal 431 and the AC power supply. This second filter circuit is, for example, a... Figure 2 The second filter circuit 28 is provided. Similarly, based on the first filter circuit 51' described above, a third filter circuit is connected between the second end of the probe terminal 611 and the processing circuit to filter out the radio frequency current in the circuit connected between the probe terminal 611 and the processing circuit. This third filter circuit is, for example, a... Figure 3 The third filter circuit 32 in the circuit.

[0071] It should be noted that the second filter circuit filters out the radio frequency (RF) current in the circuit between the second electrode terminal 431 and the AC power supply, while the first filter circuit 51 filters out the RF current on the heating element 43; their functions are different. Similarly, the third filter circuit filters out the RF current in the circuit connected between the detection terminal 611 and the processing circuit, while the first filter circuit 51' filters out the RF current on the bias detection structure 61; their functions are also different. In practical applications, at least one of the second and third filter circuits can be omitted, depending on the specific circumstances.

[0072] In some optional embodiments, the second filter circuit includes a second inductor and a second capacitor. The second inductor is connected in series between the AC power supply and the second terminal of the second electrode 431. The first electrode of the second capacitor is electrically connected to the second inductor, and the second electrode of the second capacitor is grounded. The structure and principle of this second filter circuit are similar to those of the first filter circuit described above. Similarly, the structure and principle of the third filter circuit described above are similar to those of the first filter circuit described above, and will not be described again here.

[0073] Second Embodiment

[0074] The electrostatic chuck provided in the second embodiment of the present invention differs from that in the first embodiment described above in that the structure and position of the first filter circuit are different.

[0075] Specifically, such as Figure 8 As shown, in this embodiment, the first filter circuit is connected between the second end of the second electrode terminal 431 and the AC power supply 27 (or the second filter circuit 28). The first filter circuit includes a first inductor 513 and a first capacitor 514. The electrostatic chuck also includes a hollow outer wire and an inner wire passing through the outer wire. An insulating medium is provided between the outer wire and the inner wire to electrically insulate them. The outer wire and the inner wire serve as the second electrode and the first electrode of the first capacitor 514, respectively. The two ends of the inner wire are electrically connected to the second end of the second electrode terminal 431 and the AC power supply 27 (or the second filter circuit 28), respectively. A portion of the inner wire near the second electrode terminal 431 is wound to form the first inductor 513. Figure 8 The diagram only schematically illustrates the equivalent circuit of the first inductor 513 and the first capacitor 514, and does not represent their actual structure. Their actual structure is a nested wire structure consisting of the aforementioned outer and inner wires. Optionally, the second electrode (i.e., the outer wire) of the first capacitor 514 can be grounded via the lifting shaft 72 in the bellows.

[0076] When the RF power supply applies RF power to the adsorption electrode 42, part of the RF current is applied to the heating element 43 through capacitive coupling. This part of the RF current loses some energy when passing through the first inductor 513 connected in series between the second terminal of the second electrode 431 and the AC power supply 27 (or the second filter circuit 28), and flows back to the ground potential from the grounded second electrode when passing through the first capacitor 514 connected in parallel, thereby filtering out the RF current on the heating element 43.

[0077] In some alternative embodiments, such as Figure 9 As shown, the electrostatic chuck also includes a bias detection structure 61 and a detection terminal 611 in the chuck body 41. In this case, a first filter circuit is connected between the second end of the detection terminal 611 and the processing circuit 33 (or the third filter circuit 32) to filter out the radio frequency current on the bias detection structure 61. The first filter circuit may include a first inductor 513' and a first capacitor 514', which have the same structure and filtering principle as the first inductor 513 and the first capacitor 514, respectively, and will not be described in detail here.

[0078] In summary, the electrostatic chuck provided in the above embodiments of the present invention can filter out the radio frequency current on the heating element by connecting a first filter circuit between the first end of the second electrode terminal electrically connected to the heating element and the heating element or between the second end of the second electrode terminal and the AC power supply. This can effectively reduce the risk of arcing in cables and pipe structures, and also reduce the interference of radio frequency to the matching unit, thereby ensuring that the process results are not affected and improving the consistency of the matching state of different chambers.

[0079] Third Embodiment

[0080] As another technical solution, the third embodiment of the present invention also provides a semiconductor process apparatus, such as... Figure 10 As shown, the device includes a process chamber 21 and an electrostatic chuck disposed in the process chamber 21. The electrostatic chuck is an electrostatic chuck provided in the above embodiments of the present invention. Figure 10 Semiconductor process equipment in China is designed to be set up Figure 9 Take the electrostatic chuck in the example.

[0081] The semiconductor process equipment provided in the embodiments of the present invention, by employing the electrostatic chucks provided in the above embodiments of the present invention, can effectively reduce the risk of arcing in cable and pipe structures, and can also reduce radio frequency interference to the matching unit, thereby ensuring that the process results are not affected and improving the consistency of the matching state of different chambers.

[0082] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An electrostatic chuck for use in semiconductor equipment, the electrostatic chuck comprising a chuck body, characterized in that, It also includes an adsorption electrode, a heating element, a first electrode terminal and a second electrode terminal disposed in the chuck body, wherein the first end of the first electrode terminal is electrically connected to the adsorption electrode, and the second end of the first electrode terminal is used to be electrically connected to the adsorption power supply and the radio frequency power supply. The first end of the second electrode terminal is used for electrical connection with the heating element, and the second end of the second electrode terminal is used for electrical connection with an AC power supply; a first filter circuit is connected between the first end of the second electrode terminal and the heating element, and the first filter circuit is used to filter out the radio frequency current on the heating element. The first filter circuit includes a first inductor and a first capacitor, wherein, The first inductor is connected in series between the first end of the second electrode terminal and the heating element; The first electrode of the first capacitor is connected in parallel with the first inductor, and the second electrode of the first capacitor is grounded. The chuck body includes a first body layer and a second body layer stacked together. The first body layer has a second electrode terminal extending through its thickness direction. A grounding flange, a first connecting line, and a first electrode of the first capacitor are disposed on a first surface of the first body layer facing away from the second body layer. The first electrode is electrically connected to the grounding flange via the first connecting line. On a second surface of the first body layer opposite to the second body layer, a second connecting line, a second electrode of the first capacitor, and a first coil layer of the first inductor are disposed. The second electrode is electrically connected to the second electrode terminal via the second connecting line. One end of the first coil layer is electrically connected to the second electrode, and the other end of the first coil layer has a first connecting post extending through the second body layer along its thickness direction.

2. The electrostatic chuck according to claim 1, characterized in that, The first electrode and the second electrode of the first inductor and the first capacitor are both disposed in the chuck body; wherein, the first inductor is made of wire wound together, and the first end of the first inductor is electrically connected to the heating element by welding, and the second end of the first inductor is electrically connected to the first end of the second electrode terminal by welding. The first electrode of the first capacitor is electrically connected to the second end of the first inductor by welding. The second electrode of the first capacitor is disposed opposite to the first electrode of the first capacitor in the axial direction of the chuck body. The second electrode of the first capacitor is electrically connected to the grounding flange disposed on the side of the chuck body away from its bearing surface by welding.

3. The electrostatic chuck according to claim 1, characterized in that, A second coil layer containing the heating element and the first inductor is disposed on a third surface of the second main body layer opposite to the first main body layer. One end of the second coil layer is electrically connected to the first connecting post, and the other end of the second coil layer is electrically connected to the heating element.

4. The electrostatic chuck according to claim 1, characterized in that, The second main body layer consists of multiple layers; In the multi-layer second main body layer, except for the second main body layer that is furthest from the first main body layer, the other end of the second coil layer on all the second main body layers is provided with a second connecting post. The second connecting post penetrates the adjacent second main body layer along the thickness direction of the second main body layer. The second coil layers on each of the two adjacent second main body layers are electrically connected through the second connecting post. One end of the second coil layer on the second main body layer closest to the first main body layer is electrically connected to the first connecting post; the other end of the second coil layer on the second main body layer furthest from the first main body layer is electrically connected to the heating element.

5. The electrostatic chuck according to claim 1 or 4, characterized in that, The first connecting line, the first electrode of the first capacitor, the second connecting line, the second electrode of the first capacitor, the first coil layer and the second coil layer of the first inductor, and the heating element are all made by screen printing.

6. The electrostatic chuck according to claim 1 or 4, characterized in that, The second main body layer is made by casting.

7. The electrostatic chuck according to claim 1, characterized in that, The first end of the second electrode terminal is connected to the heating element via the first filter circuit, and the second end of the second electrode terminal is connected to the AC power supply via the second filter circuit. The second filter circuit is used to filter out the radio frequency current in the circuit between the second electrode terminal and the AC power supply.

8. The electrostatic chuck according to claim 7, characterized in that, The second filter circuit includes a second inductor and a second capacitor. The second inductor is connected in series between the AC power supply and the second terminal of the second electrode. The first electrode of the second capacitor is electrically connected to the second inductor, and the second electrode of the second capacitor is grounded.

9. The electrostatic chuck according to claim 1, characterized in that, The electrostatic chuck further includes a bias detection structure and a detection terminal disposed in the chuck body, wherein the detection end of the bias detection structure extends to the bearing surface of the chuck body, the other end of the bias detection structure away from the detection end is electrically connected to the first end of the detection terminal, and the second end of the detection terminal is used for electrical connection with the processing circuit. The first filter circuit is connected between the first end of the detection terminal and the bias detection structure or between the second end of the second electrode terminal and the processing circuit. The first filter circuit is used to filter out the radio frequency current on the bias detection structure.

10. A semiconductor process apparatus, comprising a process chamber and an electrostatic chuck disposed in the process chamber, characterized in that, The electrostatic chuck is the electrostatic chuck described in any one of claims 1-9.

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