Plasma etching apparatus

Abstract

The utility model provides a kind of plasma etching equipment, the plasma etching equipment includes reaction cavity and pedestal, silicon ground ring and deposition shield ring located in reaction cavity;Silicon ground ring is arranged around pedestal, and deposition shield ring is located below silicon ground ring;Vacuum pipeline is equipped on deposition shield ring, one end of vacuum pipeline penetrates the top end of deposition shield ring, and the other end of vacuum pipeline penetrates the bottom end of deposition shield ring and is connected with a vacuum pump.The utility model can make silicon ground ring and deposition shield ring can be closely pasted together, prevent the gap between silicon ground ring and deposition shield ring, so that it can guarantee that self-bias keeps stable during etching process.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor processing and manufacturing technology, and in particular to a plasma etching device. Background Technology

[0002] Ideally, the cavity of the plasma etching equipment is gapless, the silicon ground ring is fixed in position, and the self-bias voltage (VPP) is stable. However, as the radio frequency (RF) hours increase, the screws used to fasten the silicon ground ring may loosen. Etching byproducts (polymer) generated during running can enter the gap between the silicon ground ring and the deposition shield ring, causing a change in their relative positions. This weakens the grounding performance of the silicon ground ring, resulting in self-bias voltage fluctuations. Since self-bias voltage is strongly correlated with the etching rate, this can lead to insufficient etching, resulting in yield loss or even product scrap.

[0003] It should be noted that the information disclosed in the background section of this utility model is intended only to enhance the understanding of the general background of this utility model, and should not be regarded as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0004] The purpose of this invention is to provide a plasma etching device that allows the silicon grounding ring and the deposition shielding ring to be tightly attached together, preventing gaps between them and thus ensuring that the self-bias voltage remains stable during the etching process.

[0005] To achieve the above objectives, this utility model provides a plasma etching device, including a reaction chamber and a base, a silicon grounding ring, and a deposition shielding ring located within the reaction chamber; the silicon grounding ring is arranged around the base, and the deposition shielding ring is located below the silicon grounding ring; the deposition shielding ring is provided with a vacuum pipeline, one end of the vacuum pipeline passing through the top end of the deposition shielding ring, and the other end of the vacuum pipeline passing through the bottom end of the deposition shielding ring and connected to a vacuum pump.

[0006] Optionally, the plasma etching equipment provided by this utility model further includes a pressure sensor, which is installed on the top of the deposition shielding ring and configured to monitor the pressure between the silicon grounding ring and the deposition shielding ring.

[0007] Optionally, the top of the deposition shielding ring is provided with a first mounting groove that is recessed downwards, and the pressure sensor is installed in the first mounting groove.

[0008] Optionally, the plasma etching equipment provided by this utility model further includes a monitoring probe, which is installed at the top of the deposition shielding ring and is configured to monitor the plasma signal intensity in the reaction chamber or the thickness of the etching by-products deposited on the deposition shielding ring.

[0009] Optionally, the top of the deposition shielding ring is provided with a second mounting groove that is recessed downwards, and the monitoring probe is installed in the mounting groove.

[0010] Optionally, a metal ring is also installed at the top of the deposition shielding ring, and the metal ring abuts against the silicon grounding ring.

[0011] Optionally, the top of the deposition shielding ring is further provided with a third mounting groove that is recessed downwards, and the metal ring is installed in the third mounting groove.

[0012] Optionally, the plasma etching equipment provided by this utility model further includes a fastener, the top end of which penetrates the top end of the silicon grounding ring, and the bottom end of which penetrates the bottom end of the silicon grounding ring and enters the deposition shielding ring.

[0013] Optionally, the fastener includes a screw and a washer, the washer being fitted onto the screw, with the top end of the washer abutting against the head of the screw and the bottom end of the washer abutting against the top end of the silicon grounding ring, and the threaded portion of the screw penetrating the bottom end of the silicon grounding ring and extending into the deposition shielding ring for threaded connection with the deposition shielding ring.

[0014] Optionally, the top of the deposition shielding ring is further provided with a fourth mounting groove that is recessed downwards, and the bottom of the silicon grounding ring is installed in the fourth mounting groove.

[0015] Compared with the prior art, the plasma etching equipment provided by this utility model has the following beneficial effects: The plasma etching equipment provided by this invention includes a reaction chamber and a base, a silicon grounding ring, and a deposition shielding ring located within the reaction chamber. The silicon grounding ring is arranged around the base, and the deposition shielding ring is located below the silicon grounding ring. A vacuum pipeline is provided on the deposition shielding ring, one end of which passes through the top end of the deposition shielding ring, and the other end of which passes through the bottom end of the deposition shielding ring and is connected to a vacuum pump. Therefore, by providing a vacuum pipeline connected to the vacuum pump on the deposition shielding ring, this invention allows the silicon grounding ring and the deposition shielding ring to be tightly bonded together by the negative pressure generated by the vacuum pump and the vacuum pipeline, effectively reducing the physical gap between them. This effectively prevents byproducts generated during the etching process from entering the gap between the silicon grounding ring and the deposition shielding ring, effectively avoids changes in the relative position between the silicon grounding ring and the deposition shielding ring, effectively ensures the grounding performance of the silicon grounding ring, and thus effectively ensures the stability of the self-bias voltage during the etching process, effectively avoiding self-bias voltage fluctuations.

[0016] Furthermore, by installing a pressure sensor at the top of the deposition shielding ring, this invention can monitor the pressure between the silicon grounding ring and the deposition shielding ring in real time. Under normal operating conditions (i.e., the silicon grounding ring and the deposition shielding ring are tightly fitted together without any gap), the pressure between them remains stable. When the pressure sensor detects excessive pressure (indicating an increase in etching byproducts deposited on the deposition shielding ring), a corresponding signal can be fed back to the vacuum pump to control it to increase its rotation speed, thereby maintaining a stable pressure between the silicon grounding ring and the deposition shielding ring.

[0017] Furthermore, by installing a monitoring probe at the top of the deposition shielding ring, this invention can monitor the plasma signal intensity in the reaction chamber or the thickness of etching byproducts deposited on the deposition shielding ring in real time. This allows for the triggering of an automatic cleaning program when the plasma signal intensity weakens or the etching byproducts on the deposition shielding ring become too thick. This increases the rotational speed of the vacuum pump, thereby increasing its pumping force to more effectively clean the etching byproducts deposited on the deposition shielding ring. This effectively prevents gaps between the silicon grounding ring and the deposition shielding ring, further ensuring stable self-bias voltage during the etching process and effectively avoiding self-bias voltage fluctuations. Attached Figure Description

[0018] Figure 1 A schematic diagram of the overall structure of the plasma etching equipment provided in one embodiment of this utility model.

[0019] Figure 2 A partial structural schematic diagram of a plasma etching apparatus provided in one embodiment of this utility model.

[0020] Figure 3 A self-cleaning flowchart of a plasma etching apparatus provided in one embodiment of this utility model.

[0021] The reference numerals in the attached drawings are explained as follows: Reaction chamber - 100; Base - 200; Silicon grounding ring - 300; Deposition shielding ring - 400; Flow guide hole - 410; Vacuum pipeline - 510; Vacuum pump - 520; Pressure sensor - 530; Monitoring probe - 540; Metal ring - 550; Fastener - 560; Screw - 561; Washer - 562; Suction cup - 600; Focusing ring-710; shielding ring-720; first insulating ring-730; second insulating ring-740; gas spray head-800. Detailed Implementation

[0022] The plasma etching apparatus proposed by this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of this utility model will become clearer from the following description. Please refer to the accompanying drawings to make the objectives, features, and advantages of this utility model more apparent and understandable. It should be noted that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this utility model. Any modifications to the structure, changes in proportions, or adjustments to the size, provided that the effects and objectives achieved by this utility model are the same or similar, should still fall within the scope of the technical content disclosed in this utility model. Specific design features of this utility model disclosed herein, including, for example, specific dimensions, orientations, positions, and shapes, will be determined in part by the specific application and usage environment. Furthermore, in the embodiments described below, the same reference numerals are sometimes used across different drawings to denote the same parts or parts having the same function, and repeated descriptions are omitted. In this specification, similar reference numerals and letters are used to denote similar items; therefore, once an item is defined in one figure, it need not be discussed further in subsequent figures. Furthermore, if the methods described herein involve a series of steps, and the order of these steps presented herein is not necessarily the only possible order in which they can be performed, some of the described steps may be omitted and / or other steps not described herein may be added to the method.

[0023] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor should they be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The singular forms “a,” “one,” and “the” include plural objects. The term “or” is generally used to mean “and / or.” The term “several” is generally used to mean “at least one.” The term “at least two” is generally used to mean “two or more.” The term “multiple” is generally used to mean “at least two.”

[0024] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, in this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Moreover, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0025] The core idea of ​​this invention is to provide a plasma etching device that allows the silicon grounding ring and the deposition shielding ring to be tightly attached together, preventing gaps between them and thus ensuring that the self-bias voltage remains stable during the etching process.

[0026] To achieve the above-mentioned goals, this utility model provides a plasma etching device, please refer to... Figure 1 and Figure 2 ,in, Figure 1 A schematic diagram of the overall structure of the plasma etching equipment provided in one embodiment of this utility model; Figure 2 This is a partial structural schematic diagram of a plasma etching apparatus provided in one embodiment of the present invention. Figure 1 and Figure 2As shown, the plasma etching equipment provided by this utility model includes a reaction chamber 100 and a base 200, a silicon grounding ring 300, and a deposition shielding ring 400 located within the reaction chamber 100; the silicon grounding ring 300 is arranged around the base 200, and the deposition shielding ring 400 is located below the silicon grounding ring 300; a vacuum pipeline 510 is provided on the deposition shielding ring 400, one end of the vacuum pipeline 510 passes through the top end of the deposition shielding ring 400, and the other end of the vacuum pipeline 510 passes through the bottom end of the deposition shielding ring 400 and is connected to a vacuum pump 520.

[0027] Therefore, by providing a vacuum pipeline 510 connected to the vacuum pump 520 on the deposition shielding ring 400, the present invention allows the silicon grounding ring 300 and the deposition shielding ring 400 to be tightly bonded together by the negative pressure generated by the vacuum pump 520 and the vacuum pipeline 510, effectively reducing the physical gap between them. This effectively prevents byproducts generated during the etching process from entering the gap between the silicon grounding ring 300 and the deposition shielding ring 400, effectively avoids changes in the relative position between the silicon grounding ring 300 and the deposition shielding ring 400, effectively ensures the grounding performance of the silicon grounding ring 300, and thus effectively ensures that the self-bias voltage remains stable during the etching process, effectively avoiding the occurrence of self-bias voltage fluctuations.

[0028] It should be noted that, as those skilled in the art will understand, during plasma etching, the RF power supply applies energy through the base 200 to excite the gas to form plasma. Since plasma itself is conductive, a complete return loop to ground is required. By providing a silicon grounding ring 300 surrounding the base 200 within the reaction chamber 100 of the plasma etching equipment, a stable and controllable RF grounding loop path can be provided. By fixing the position of the grounding point, the RF impedance within the entire reaction chamber 100 can be kept stable. Because etching byproducts are deposited on all surfaces inside the cavity during plasma etching, a deposition shielding ring 400 within the reaction chamber 100 of the plasma etching equipment can capture polymers that would otherwise be deposited on more difficult-to-clean cavity components (such as the inner wall of the reaction chamber 100 and the base 200). Since the deposition shielding ring 400 is a relatively independent and easily removable ring component, when the etching byproducts deposited on the deposition shielding ring 400 become too thick, the shielding deposition ring can be removed for cleaning or directly replaced. This significantly shortens the maintenance time of the plasma etching equipment and effectively improves equipment utilization. Furthermore, by placing the deposition shielding ring 400 below the silicon grounding ring 300, the radio frequency signal applied to the base 200 can be shielded within the base 200, thereby achieving electrical isolation between the base 200 and the silicon grounding ring 300.

[0029] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this invention further includes a pressure sensor 530, which is mounted on the top of the deposition shielding ring 400 and configured to monitor the pressure between the silicon grounding ring 300 and the deposition shielding ring 400.

[0030] Therefore, by setting a pressure sensor 530 at the top of the deposition shielding ring 400, this utility model can monitor the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 in real time. Since the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 is kept stable under normal operating conditions (i.e., the silicon grounding ring 300 and the deposition shielding ring 400 are tightly attached together without any gap), when the pressure sensor 530 detects that the pressure is too high (indicating that the etching byproducts deposited on the deposition shielding ring 400 have increased), a corresponding signal can be fed back to the vacuum pump 520 to control the vacuum pump 520 to increase its rotation speed, thereby keeping the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 stable.

[0031] Please continue to refer to this. Figure 1 and Figure 2 ,like Figure 1 and Figure 2 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this invention further includes a controller (not shown) communicatively connected to the pressure sensor 530, the controller being configured to control the vacuum pump 520 to increase its rotational speed when the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 is greater than a preset pressure threshold.

[0032] Therefore, when the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 exceeds a preset pressure threshold (i.e., when the amount of etching byproducts deposited on the deposition shielding ring 400 increases), the controller can automatically control the vacuum pump 520 to increase its rotation speed. This allows for the automatic cleaning of the etching byproducts deposited on the deposition shielding ring 400, effectively preventing gaps from forming between the silicon grounding ring 300 and the deposition shielding ring 400. This further ensures that the self-bias voltage remains stable during the etching process and effectively avoids the occurrence of self-bias voltage fluctuations.

[0033] It should be noted that, as those skilled in the art will understand, this utility model does not limit the specific type of the controller. More details about the controller can be adapted by referring to relevant content known to those skilled in the art, and will not be elaborated here.

[0034] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the top end of the deposition shielding ring 400 is provided with a first mounting groove (not shown in the figure) that is recessed downwards, and the pressure sensor 530 is mounted in the first mounting groove. Therefore, by providing a first mounting groove at the top end of the deposition shielding ring 400, not only is it easier to install the pressure sensor 530, but it also saves space and helps to simplify the overall structure of the deposition shielding ring 400.

[0035] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this invention further includes a monitoring probe 540, which is mounted on the top of the deposition shielding ring 400. The monitoring probe 540 is configured to monitor the plasma signal intensity in the reaction chamber 100 or the thickness of the etching byproducts deposited on the deposition shielding ring 400.

[0036] Therefore, by installing a monitoring probe 540 at the top of the deposition shielding ring 400, this invention can monitor the plasma signal intensity in the reaction chamber 100 or the thickness of the etching byproducts deposited on the deposition shielding ring 400 in real time. This allows for the triggering of an automatic cleaning program when the plasma signal intensity in the reaction chamber 100 weakens or the thickness of the etching byproducts deposited on the deposition shielding ring 400 becomes excessive. This increases the rotational speed of the vacuum pump 520, enabling it to increase its pumping force and more effectively clean the etching byproducts deposited on the deposition shielding ring 400. This effectively prevents gaps between the silicon grounding ring 300 and the deposition shielding ring 400, further ensuring stable self-bias voltage during the etching process and effectively avoiding self-bias voltage fluctuations.

[0037] In some exemplary embodiments, the monitoring probe 540 is communicatively connected to the controller, which is further configured to control the vacuum pump 520 to increase its rotational speed when the plasma signal intensity in the reaction chamber 100 is less than a preset intensity threshold or the thickness of the etching byproducts deposited on the deposition shielding ring 400 is greater than a preset thickness threshold.

[0038] Therefore, the controller can automatically control the vacuum pump 520 to increase its rotation speed when the plasma signal intensity in the reaction chamber 100 is less than a preset intensity threshold or the thickness of the etching byproducts deposited on the deposition shielding ring 400 is greater than a preset thickness threshold. This allows the vacuum pump to automatically clean the etching byproducts deposited on the deposition shielding ring 400, effectively preventing gaps between the silicon grounding ring 300 and the deposition shielding ring 400, further ensuring that the self-bias voltage remains stable during the etching process, and effectively avoiding the occurrence of self-bias voltage fluctuations.

[0039] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the top end of the deposition shielding ring 400 is provided with a downwardly recessed second mounting groove (not shown in the figure), and the monitoring probe 540 is mounted in the mounting groove. Therefore, by providing a second mounting groove at the top end of the deposition shielding ring 400, not only is the installation of the monitoring probe 540 easier, but space is also saved, further simplifying the overall structure of the deposition shielding ring 400.

[0040] It should be noted that, as those skilled in the art will understand, the monitoring probe 540 can be, but is not limited to, an optical emission spectroscopy (OES) probe. The OES probe can monitor plasma characteristic peaks (such as CF2, F) within the reaction chamber 100 in real time, and can accurately calculate the thickness of etching byproducts deposited on the deposition shielding ring 400 (with an accuracy of ±5 nm). It should also be noted that, as those skilled in the art will understand, this invention does not limit the specific values ​​of the preset intensity threshold and the preset thickness threshold; the specific values ​​of the preset intensity threshold and the preset thickness threshold can be set according to actual needs.

[0041] Please continue to refer to this. Figure 3 This is a self-cleaning flowchart of a plasma etching apparatus provided in one embodiment of this utility model. Figure 3 As shown, when the attenuation of the plasma signal intensity detected by the optical emission spectroscopy (OES) probe exceeds a certain level (e.g., a 15% decrease in CF2 signal intensity), that is, when the plasma signal intensity detected by the optical emission spectroscopy (OES) probe is lower than a preset intensity threshold (e.g., 85%), the controller will send a start signal to the vacuum pump 520 to initiate the self-cleaning program, increase the rotation speed of the vacuum pump 520, and increase the pumping force, thereby effectively cleaning the etching byproducts deposited on the deposition shielding ring 400, effectively preventing gaps from forming between the silicon grounding ring 300 and the deposition shielding ring 400, further ensuring that the self-bias voltage remains stable during the etching process, and effectively avoiding the occurrence of self-bias voltage fluctuations.

[0042] It should also be noted that, as those skilled in the art will understand, in order to ensure that the monitoring probe 540 can successfully monitor the plasma signal intensity within the reaction chamber 100 or the thickness of etching byproducts deposited on the deposition shielding ring 400, the monitoring probe 540 can be positioned in the area at the top of the deposition shielding ring 400 that does not contact the silicon grounding ring 300, so as to ensure that the silicon grounding ring 300 does not obstruct the monitoring probe 540. Alternatively, the monitoring probe 540 can be positioned in the area at the top of the deposition shielding ring 400 that contacts the silicon grounding ring 300. In this case, a transparent window (through the top and bottom of the silicon grounding ring 300) can be provided on the silicon grounding ring 300, with the transparent window located directly above the monitoring probe 540, so that the light emitted by the plasma within the reaction chamber 100 can smoothly reach the monitoring probe 540 through the transparent window.

[0043] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, a metal ring 550 is also mounted on the top of the deposition shielding ring 400, the metal ring 550 abutting against the silicon grounding ring 300.

[0044] Therefore, by providing a metal ring 550 at the top of the deposition shielding ring 400 that can abut against the silicon grounding ring 300, this utility model can provide a continuous and stable grounding pressure to effectively ensure the grounding performance of the silicon grounding ring 300.

[0045] It should be noted that, as those skilled in the art will understand, the specific material of the metal ring 550 is not limited in this invention, and the metal ring 550 can be, but is not limited to, an iron wire ring. It should also be noted that, as those skilled in the art will understand, the metal ring 550 has a certain elastic deformation capability, that is, the metal ring 550 can elastically deform according to the change in the gap between the silicon grounding ring 300 and the deposition shielding ring 400.

[0046] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the top of the deposition shielding ring 400 is further provided with a third mounting groove (not shown in the figure) that is recessed downwards, and the metal ring 550 is installed in the third mounting groove.

[0047] Therefore, by providing a third mounting groove at the top of the deposition shielding ring 400, it is not only easier to install the metal ring 550, but also to limit the metal ring 550, effectively preventing the metal ring 550 from falling off between the silicon grounding ring 300 and the deposition shielding ring 400, so as to ensure that the metal ring 550 can provide continuous and stable grounding pressure, thereby effectively guaranteeing the grounding performance of the silicon grounding ring 300.

[0048] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this utility model further includes a fastener 560, the top end of which penetrates the top end of the silicon grounding ring 300, and the bottom end of which penetrates the bottom end of the silicon grounding ring 300 and enters the deposition shielding ring 400.

[0049] Therefore, by setting a fastener 560 with its top end penetrating through the top end of the silicon grounding ring 300 and its bottom end penetrating through the bottom end of the silicon grounding ring 300 and entering the deposition shielding ring 400, the connection between the silicon grounding ring 300 and the deposition shielding ring 400 can be made more secure.

[0050] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the fastener 560 includes a screw 561 and a washer 562, the washer 562 being fitted onto the screw 561, with the top end of the washer 562 abutting against the head of the screw 561 and the bottom end of the washer 562 abutting against the top end of the silicon grounding ring 300. The threaded portion of the screw 561 passes through the bottom end of the silicon grounding ring 300 and extends into the deposition shielding ring 400 for threaded connection with the deposition shielding ring 400.

[0051] Therefore, by configuring the fastener 560 as a structure including a screw 561 and a washer 562, the present invention can achieve a stable connection between the silicon grounding ring 300 and the deposition shielding ring 400 through the screw 561. Since the washer 562 is fitted onto the screw 561, and the top end of the washer 562 abuts against the head of the screw 561, and the bottom end of the washer 562 abuts against the top end of the silicon grounding ring 300, the washer 562 can prevent the head of the screw 561 from directly contacting the silicon grounding ring 300, thus avoiding pressure concentration that could damage the silicon grounding ring 300.

[0052] Please continue to refer to this. Figure 2 ,like Figure 2As shown, in some exemplary embodiments, the deposition shielding ring 400 is provided with a plurality of flow guide holes 410 extending through its top and bottom ends. Thus, by providing a plurality of flow guide holes 410 extending through its top and bottom ends on the deposition shielding ring 400, an optimal path can be provided for the flow of cleaning gas and the discharge of etching byproducts during periodic maintenance of the plasma etching equipment.

[0053] Please continue to refer to this. Figure 2 ,like Figure 2 As shown, in some exemplary embodiments, the top end of the deposition shielding ring 400 is further provided with a downwardly recessed fourth mounting groove (not shown in the figure), and the bottom end of the silicon grounding ring 300 is installed in the fourth mounting groove. Therefore, by providing a fourth mounting groove at the top end of the deposition shielding ring 400 and installing the bottom end of the silicon grounding ring 300 in the fourth mounting groove, the silicon grounding ring 300 can be further limited, effectively preventing the silicon grounding ring 300 from shaking.

[0054] Please continue to refer to this. Figure 1 ,like Figure 1 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this invention further includes a suction cup 600, which is mounted on the top of the base 200. Thus, the suction cup 600 can provide electrostatic adsorption force to firmly hold the wafer to be processed.

[0055] Please continue to refer to this. Figure 1 ,like Figure 1 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this invention further includes a focusing ring 710 disposed within the reaction chamber 100, the focusing ring 710 surrounding the wafer mounted on the chuck 600. Thus, by providing a focusing ring 710 surrounding the wafer, the electric field distribution at the edge of the base 200 can be made smoother, reducing the electric field concentration effect at the edge, and making the plasma density and ion bombardment energy more uniformly distributed in the wafer radius direction, thereby ensuring more uniform etching across the entire wafer surface.

[0056] Please continue to refer to this. Figure 1 ,like Figure 1 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this invention further includes a shielding ring 720 disposed within the reaction chamber 100, the shielding ring 720 surrounding the silicon grounding ring 300. Thus, by providing the shielding ring 720 surrounding the silicon grounding ring 300 within the reaction chamber 100, the plasma can be partially shielded to prevent corrosion of the silicon grounding ring 300 by the plasma.

[0057] Please continue to refer to this. Figure 1 ,like Figure 1 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this invention further includes a first insulating ring 730 and a second insulating ring 740 disposed within the reaction chamber 100. The first insulating ring 730 is fixed to the outside of the base 200, and the second insulating ring 740 is fixed to the outside of the first insulating ring 730. Thus, by providing the first insulating ring 730 fixed to the outside of the base 200 and the second insulating ring 740 fixed to the outside of the first insulating ring 730 within the reaction chamber 100, the base 200 can be electrically isolated from the silicon grounding ring 300.

[0058] Please continue to refer to this. Figure 1 ,like Figure 1 As shown, in some exemplary embodiments, the plasma etching apparatus provided by this utility model further includes a gas spray head 800 disposed in the reaction chamber 100. The gas spray head 800 is connected to a gas supply device (not shown in the figure) for supplying reaction gas to the reaction chamber 100 during plasma etching. The gas spray head 800 is located above the base 200 and opposite to the base 200.

[0059] It should be noted that, as those skilled in the art will understand, further details regarding the plasma etching equipment can be adapted by referring to content known to those skilled in the art, and will not be elaborated upon here.

[0060] In summary, compared with the prior art, the plasma etching equipment provided by this utility model has the following beneficial effects: (1) This utility model provides a vacuum pipeline 510 connected to a vacuum pump 520 on the deposition shielding ring 400 located below the silicon grounding ring 300. Under the negative pressure generated by the vacuum pump 520 and the vacuum pipeline 510, the silicon grounding ring 300 and the deposition shielding ring 400 can be tightly attached together by the pressure difference, effectively reducing the physical gap between them. This effectively prevents byproducts generated during the etching process from entering the gap between the silicon grounding ring 300 and the deposition shielding ring 400, effectively avoids changes in the relative position between the silicon grounding ring 300 and the deposition shielding ring 400, effectively ensures the grounding performance of the silicon grounding ring 300, and thus effectively ensures that the self-bias voltage remains stable during the etching process, effectively avoiding the occurrence of self-bias voltage fluctuations.

[0061] (2) By setting a pressure sensor 530 at the top of the deposition shielding ring 400, the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 can be monitored in real time. Under normal operating conditions (i.e., the silicon grounding ring 300 and the deposition shielding ring 400 are tightly attached together without any gap), the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 remains stable. When the pressure detected by the pressure sensor 530 is too high (indicating an increase in etching byproducts deposited on the deposition shielding ring 400), a corresponding signal can be fed back to the vacuum pump 520 to control the vacuum pump 520 to increase its rotation speed, thereby keeping the pressure between the silicon grounding ring 300 and the deposition shielding ring 400 stable.

[0062] (3) By installing a monitoring probe 540 at the top of the deposition shielding ring 400, the present invention can monitor the plasma signal intensity in the reaction chamber 100 or the thickness of the etching byproducts deposited on the deposition shielding ring 400 in real time. Thus, when the plasma signal intensity in the reaction chamber 100 weakens or the thickness of the etching byproducts deposited on the deposition shielding ring 400 becomes too thick, an automatic cleaning program can be triggered to increase the rotation speed of the vacuum pump 520. This allows the vacuum pump 520 to increase its pumping force and more effectively clean the etching byproducts deposited on the deposition shielding ring 400. This effectively prevents gaps from forming between the silicon grounding ring 300 and the deposition shielding ring 400, further ensuring that the self-bias voltage remains stable during the etching process and effectively avoiding the occurrence of self-bias voltage fluctuations.

[0063] (4) By providing a metal ring 550 that can abut against the silicon grounding ring 300 at the top of the deposition shielding ring 400, this utility model can provide a continuous and stable grounding pressure to effectively ensure the grounding performance of the silicon grounding ring 300.

[0064] It should be noted that in the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0065] The above description is merely a description of a preferred embodiment of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the present invention. Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the present invention and its equivalents, the present invention also intends to include these modifications and variations.

Claims

1. A plasma etching apparatus, characterized in that, Includes a reaction chamber and a base, a silicon grounding ring, and a deposition shielding ring located within the reaction chamber; The silicon grounding ring is arranged around the base, and the deposited shielding ring is located below the silicon grounding ring; The deposition shielding ring is equipped with a vacuum pipeline. One end of the vacuum pipeline passes through the top of the deposition shielding ring, and the other end of the vacuum pipeline passes through the bottom of the deposition shielding ring and is connected to a vacuum pump.

2. The plasma etching apparatus according to claim 1, characterized in that, It also includes a pressure sensor mounted on the top of the deposition shielding ring, the pressure sensor being configured to monitor the pressure between the silicon grounding ring and the deposition shielding ring.

3. The plasma etching apparatus according to claim 2, characterized in that, The top of the deposition shielding ring is provided with a first mounting groove that is recessed downwards, and the pressure sensor is installed in the first mounting groove.

4. The plasma etching apparatus according to claim 1, characterized in that, It also includes a monitoring probe, which is mounted on the top of the deposition shielding ring and is configured to monitor the plasma signal intensity in the reaction chamber or the thickness of etching byproducts deposited on the deposition shielding ring.

5. The plasma etching apparatus according to claim 4, characterized in that, The top of the deposition shielding ring is provided with a second mounting groove that is recessed downwards, and the monitoring probe is installed in the mounting groove.

6. The plasma etching apparatus according to claim 1, characterized in that, A metal ring is also installed at the top of the deposition shielding ring, and the metal ring abuts against the silicon grounding ring.

7. The plasma etching apparatus according to claim 6, characterized in that, The top of the deposition shielding ring is also provided with a third mounting groove that is recessed downwards, and the metal ring is installed in the third mounting groove.

8. The plasma etching apparatus according to claim 1, characterized in that, It also includes a fastener, the top end of which penetrates the top end of the silicon grounding ring, and the bottom end of which penetrates the bottom end of the silicon grounding ring and enters the deposited shielding ring.

9. The plasma etching apparatus according to claim 8, characterized in that, The fastener includes a screw and a washer. The washer is fitted onto the screw, with the top end of the washer abutting against the head of the screw and the bottom end of the washer abutting against the top end of the silicon grounding ring. The threaded portion of the screw passes through the bottom end of the silicon grounding ring and extends into the deposition shielding ring for threaded connection with the deposition shielding ring.

10. The plasma etching apparatus according to claim 1, characterized in that, The top of the deposition shielding ring is also provided with a fourth mounting groove that is recessed downwards, and the bottom of the silicon grounding ring is installed in the fourth mounting groove.

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