Hierarchical electrostatic adsorption etching device

Abstract

The present application discloses a hierarchical electrostatic adsorption etching device, comprising a studio, a carrier, a first electrostatic suction cup and a second electrostatic suction cup. The first electrostatic suction cup and the second electrostatic suction cup are arranged in the studio and above the carrier. The electrostatic suction cup can attract impurity particles to adhere, thereby ensuring the cleanliness of the cavity environment, extending the cavity maintenance cycle, and improving the equipment operation efficiency; the second electrostatic suction cup is provided with a first perforation, and the impurity particles can move toward the first electrostatic suction cup through the first perforation; the attraction of the first electrostatic suction cup is greater than the attraction of the second electrostatic suction cup; a second electrostatic suction cup with smaller attraction is added below the first electrostatic suction cup, which will not affect the carrier's attraction to positive ions, and can well induce impurity particles with small splash angles and low splash heights to move upward; the impurity particles are mainly attached to the first electrostatic suction cup, which can keep the impurity particles away from the etching gas source, thereby avoiding airflow disturbance that has already been adsorbed. Impurity particles.

Description

Technical Field

[0001] The present application relates to the field of wafer etching technology, and in particular to a hierarchical electrostatic adsorption etching device. Background Art

[0002] Plasma etching is a method of wafer surface treatment. Radio frequency inductively coupled gas discharge is one of the important ways to generate plasma. In an inductively coupled system, power is directly applied to a coil outside a vacuum chamber. The electromagnetic field energy generated by the coil is gathered in the vacuum chamber, exciting gas discharge to form plasma, so that positively charged ions bombard the wafer surface, thereby removing natural oxides or fluorocarbon residues on the wafer surface, and finally etching the desired shape on the wafer surface.

[0003] During the wafer etching process, impurity particles such as oxides and nitrides will be generated. These particles will adhere to the wall of the working chamber under the action of etching; as the etching continues, the particles accumulated on the wall will fall off. If the impurity particles fall onto the surface of the wafer, it will affect the surface process of the wafer. Summary of the invention

[0004] The purpose of the present application is to overcome the deficiencies in the prior art and to provide a hierarchical electrostatic adsorption etching device.

[0005] To achieve the above technical objectives, the present application provides a hierarchical electrostatic adsorption etching device, including: a studio, used to provide space for wafer etching; a carrier, arranged in the studio, used to receive the wafer; a first electrostatic suction cup, arranged in the studio and above the carrier; a second electrostatic suction cup, arranged in the studio and between the first electrostatic suction cup and the carrier; during the etching process, the first electrostatic suction cup and the second electrostatic suction cup are energized, have electric field attraction, and can attract impurity particles to adhere; wherein, the second electrostatic suction cup is provided with a first perforation, and impurity particles can move toward the first electrostatic suction cup through the first perforation; the attraction of the first electrostatic suction cup is greater than the attraction of the second electrostatic suction cup.

[0006] Furthermore, the first electrostatic chuck and / or the second electrostatic chuck includes: a first electrode connected to the positive pole of the power supply, used to attract negatively charged impurity particles; a second electrode connected to the negative pole of the power supply, used to attract positively charged impurity particles; wherein the area of ​​the first electrode is greater than the area of ​​the second electrode.

[0007] Furthermore, the hierarchical electrostatic adsorption etching device also includes a third electrostatic chuck, which is arranged in the working chamber and between the second electrostatic chuck and the carrier; the third electrostatic chuck is provided with a second perforation, and impurity particles can move toward the second electrostatic chuck through the second perforation; the attraction of the second electrostatic chuck is greater than the attraction of the third electrostatic chuck.

[0008] Furthermore, the hierarchical electrostatic adsorption etching device also includes: a first power supply component for supplying power to the first electrostatic suction cup; a second power supply component for supplying power to the second electrostatic suction cup; and a third power supply component for supplying power to the third electrostatic suction cup, wherein the output voltages of the first power supply component, the second power supply component and the third power supply component increase by 20% respectively.

[0009] Furthermore, the diameter of the second perforation is larger than that of the first perforation; and / or at least part of the second perforation is staggered with the first perforation.

[0010] Furthermore, the hierarchical electrostatic adsorption etching device also includes a gas supply component, which is used to blow air to the first electrostatic chuck, the second electrostatic chuck and the third electrostatic chuck to blow away foreign particles adhering thereto and play a cleaning role.

[0011] Furthermore, the air supply assembly includes: a first group of air nozzles, connecting the air supply equipment and the working room and arranged below the first electrostatic suction cup, capable of blowing air from bottom to top toward the first electrostatic suction cup; a second group of air nozzles, connecting the air supply equipment and the working room and arranged below the second electrostatic suction cup, capable of blowing air from bottom to top toward the second electrostatic suction cup; a third group of air nozzles, connecting the air supply equipment and the working room and arranged below the third electrostatic suction cup, capable of blowing air from bottom to top toward the third electrostatic suction cup.

[0012] Furthermore, the gas supply assembly also includes a direction-changing adjustment member, which is used to change the blowing direction of the first group of gas nozzles, the second group of gas nozzles and / or the third group of gas nozzles; when the blowing direction of the first group of gas nozzles changes, the first group of gas nozzles can blow air from top to bottom toward the second electrostatic suction cup; when the blowing direction of the second group of gas nozzles changes, the second group of gas nozzles can blow air from top to bottom toward the third electrostatic suction cup; when the blowing direction of the third group of gas nozzles changes, the third group of gas nozzles can blow air from top to bottom toward the working room, thereby realizing the supply of etching gas.

[0013] Furthermore, the studio includes: a base, a carrier is arranged in the base, and a wafer inlet and outlet are arranged on one side of the base; a dielectric cover is arranged on the base and is sealed and connected to the base; wherein the hierarchical electrostatic adsorption etching device also includes a coil, the coil is wound outside the dielectric cover, and the positions of the first electrostatic suction cup and the second electrostatic suction cup are higher than the coil; during the etching process, the coil is energized, can ionize the etching gas, generate plasma, and the carrier is energized, generates a negative bias potential, and can attract positive ions to bombard the wafer; the attraction of the carrier to charged particles is greater than the attraction of the first electrostatic suction cup and the second electrostatic suction cup to charged particles.

[0014] Furthermore, the medium cover includes: a cylinder portion, which is arranged in a cylindrical shape, with the upper and lower ends of the cylinder portion open, and the lower end of the cylinder portion is connected to the base; a cover portion, which is used to seal the upper end of the cylinder portion; the hierarchical electrostatic adsorption etching device also includes a bracket, which is used to layer the first electrostatic suction cup and the second electrostatic suction cup; the bracket is arranged on the cover portion, and when the cover portion is connected to the cylinder portion, the bracket is hoisted in the medium cover.

[0015] The present application provides a hierarchical electrostatic adsorption etching device, including a studio, a carrier, a first electrostatic suction cup and a second electrostatic suction cup, wherein the first electrostatic suction cup and the second electrostatic suction cup are arranged in the studio and above the carrier, and during the etching process, the first electrostatic suction cup and the second electrostatic suction cup can attract impurity particles to attach; the electrostatic suction cup can not only actively attract impurity particles, but also ensure the stability of the adhesion of impurity particles, therefore, the provision of the electrostatic suction cup can not only ensure the cleanliness of the cavity environment, but also extend the maintenance cycle of the cavity and improve the operation efficiency of the equipment; the second electrostatic suction cup is provided with a first perforation, and impurity particles can move toward the first electrostatic suction cup through the first perforation; the attraction of the first electrostatic suction cup is greater than the attraction of the second electrostatic suction cup; a second electrostatic suction cup with a smaller attraction is added below the first electrostatic suction cup, which will not affect the carrier's attraction to positive ions, but can also well induce impurity particles with a small splash angle and a low splash height to move upward; the impurity particles are mainly attached to the first electrostatic suction cup, which can keep the impurity particles away from the etching gas source, thereby avoiding airflow disturbance of the already adsorbed impurity particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of a hierarchical electrostatic adsorption etching device provided in this application;

[0017] Figure 2 for Figure 1 The schematic diagram of the structure of the three-layer electrostatic chuck in the hierarchical electrostatic adsorption etching device shown;

[0018] Figure 3 for Figure 2 A schematic diagram of the structure of the three-layer electrostatic chuck in another direction is shown;

[0019] Figure 4 for Figure 1 The structure diagram of the hierarchical electrostatic adsorption etching device shown is omitting the base and the carrier;

[0020] Figure 5 for Figure 4 The structure diagram of the hierarchical electrostatic adsorption etching device shown is omitting the electrostatic chuck;

[0021] Figure 6 A schematic diagram of the structure of a direction-changing adjustment member and a gas nozzle provided in this application;

[0022] Figure 7 for Figure 6 The schematic diagram of the air nozzle after it changes direction upwards is shown;

[0023] Figure 8 for Figure 6 The schematic diagram of the air nozzle after it is turned downwards is shown;

[0024] Fig. 9 A schematic diagram of the structure of another direction-changing adjustment member and air nozzle provided in this application. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0026] The present application provides a hierarchical electrostatic adsorption etching device, including: a studio 110, used to provide space for wafer etching; a carrier 120, arranged in the studio 110, used to receive the wafer; a first electrostatic suction cup 210, arranged in the studio 110 and above the carrier 120; a second electrostatic suction cup 220, arranged in the studio 110 and between the first electrostatic suction cup 210 and the carrier 120; during the etching process, the first electrostatic suction cup 210 and the second electrostatic suction cup 220 are energized, have electric field attraction, and can attract impurity particles to adhere.

[0027] For details, please refer to Figure 1 In the illustrated embodiment, the studio 110 includes a base 111 and a dielectric cover 112; the carrier 120 is disposed in the base 111; an open hole is provided on the top of the base 111, and the dielectric cover 112 is arranged in a cylindrical shape and is covered on the top of the base 111 and is sealed and connected to the base 111; through the open hole, the inner cavity of the base 111 and the inner cavity of the dielectric cover 112 are connected to form an etching chamber.

[0028] Continue to refer to Figure 1 A wafer inlet and outlet are provided on one side of the base 111, and a wafer handling mechanism such as a robot can transfer the wafer to the etching chamber through the wafer inlet and outlet. An air inlet channel and an air outlet channel are also provided on the base 111. The air inlet channel connects the etching chamber and the gas supply device, and the air outlet channel connects the etching chamber and the exhaust device. The gas supply device can pass the etching gas into the etching chamber through the air inlet channel, and the exhaust device can extract the gas in the etching chamber through the air outlet channel; the gas supply device and the exhaust device cooperate to maintain the intracavity air pressure required for etching work.

[0029] Furthermore, the etching device further includes a coil 130, which is wound outside the dielectric cover 112. The coil 130 is connected to a first RF power source, which is used to supply power to the coil 130. When working, the coil 130 is energized, generates glow discharge, and can ionize the etching gas to generate plasma.

[0030] For details, please refer to Figure 1 In the illustrated embodiment, the coil 130 spirally extends along the vertical direction around the outer wall of the medium cover 112. The first electrostatic chuck 210 and the second electrostatic chuck 220 are arranged in the medium cover 112 at intervals along the vertical direction; the first electrostatic chuck 210 is located higher than the second electrostatic chuck 220, and the second electrostatic chuck 220 is located higher than the coil 130.

[0031] The dielectric cover 112 is made of ceramic to facilitate coupling of the radio frequency energy of the coil 130 into the working chamber 110 .

[0032] Furthermore, the etching device further includes an outer cover 113, which is sleeved outside the dielectric cover 112 and the coil 130 and supported by the base 111. The base 111 and the outer cover 113 are made of metal materials and are grounded to ensure power safety.

[0033] Furthermore, the carrier 120 is connected to a second RF power supply, which is used to supply power to the carrier 120. When the carrier 120 is powered on, the RF energy induces bias voltage and generates a negative bias potential, which can attract positive ions to accelerate toward the carrier 120, so as to etch the wafer to remove surface materials.

[0034] For details, please refer to Figure 1 In the illustrated embodiment, the carrier 120 is disposed in the base 111 and has a lifting function. When the carrier 120 is in a low position, it faces the wafer inlet and outlet, and the wafer handling mechanism can transfer the wafer to the carrier 120 through the wafer inlet and outlet; after the carrier 120 receives the wafer, it moves vertically upward and approaches the dielectric cover 112 and the coil 130. It is easy to understand that during the etching process, the plasma concentration within the range surrounded by the coil 130 is high, so that the carrier 120 carries the wafer close to the coil 130, and the carrier 120 can efficiently attract positive ions and etch the wafer.

[0035] In a specific embodiment, the coil 130 is powered by a first RF power supply with a frequency of 400kHz, and the carrier 120 is powered by a second RF power supply with a frequency of 13.56MHz. After the carrier 120 receives the wafer, argon gas with a flow rate of 12sccm is introduced into the etching chamber; the coil 130 is powered by the first RF power supply, and the power of the first RF power supply is 200W. The alternating magnetic field generated by the RF current in the coil 130 can pass through the dielectric window and act on the etching gas, thereby stimulating gas discharge, accelerating electron movement, and promoting plasma generation; the carrier 120 is powered by the second RF power supply, and the power of the second RF power supply is 400W. The carrier 120 can generate a negative bias potential, thereby acting as a cathode to attract positively charged gas atoms to accelerate toward the carrier 120; after etching for 40s, the power is turned off, the gas flow is stopped, the etched wafer is taken out, and the next wafer to be etched is waited for input.

[0036] It should be explained that ions are mainly generated by electron collisions. During the etching process, positively charged gas atoms are generated through electron collision ionization and electron collision dissociation; when the positively charged gas atoms bombard the wafer, the natural oxide or fluorocarbon residue on the surface of the wafer can be removed; the removed surface material is usually in a charged particle state, and the impurity particles described in this application are these etching generated particles.

[0037] It is also necessary to explain that when positive ions bombard the wafer downward and generate impurity particles, the impurity particles bombarded have an initial velocity and will splash upward. During the splashing process, some impurity particles stick to the inner wall of the working chamber 110, and some impurity particles continue to collide with electrons and gas atoms in the cavity.

[0038] In order to prevent the ejected impurity particles from staying in the etching chamber and affecting the environment inside the chamber, an electrostatic chuck is provided in the studio 110 to be protected by the present application. The electrostatic chuck is arranged above the carrier 120. When powered on, the electrostatic chuck can attract charged impurity particles.

[0039] It is easy to understand that compared with ordinary cavity walls, electrostatic chucks that are charged after power is turned on and have the characteristic of opposite charges attracting each other are more attractive to charged impurity particles. In the actual etching process, even if the splashing direction of the impurity particles is not directed to the electrostatic chuck, as long as the impurity particles move upward, they will eventually move toward the electrostatic chuck and attach to the electrostatic chuck under the induction of the electric field force. At the same time, compared with ordinary cavity walls, electrostatic chucks can absorb more impurity particles and ensure the stability of the attachment of impurity particles.

[0040] The electrostatic chuck can not only actively attract foreign particles, but also ensure the stability of the adhesion of foreign particles. Therefore, the provision of the electrostatic chuck can not only ensure the cleanliness of the cavity environment, but also extend the maintenance cycle of the cavity and improve the operating efficiency of the equipment.

[0041] The working room 110 to be protected by the present application is provided with two electrostatic chucks, which are spaced apart in the vertical direction. Figure 1 In the illustrated embodiment, the first electrostatic chuck 210 and the second electrostatic chuck 220 are disposed in the dielectric cover 112 and suspended above the coil 130 and the carrier 120; wherein the first electrostatic chuck 210 is disposed on the top and the second electrostatic chuck 220 is disposed on the bottom; the second electrostatic chuck 220 is closer to the carrier 120 than the first electrostatic chuck 210.

[0042] Furthermore, the second electrostatic chuck 220 is provided with a first through-hole 220 a , and foreign particles can move toward the first electrostatic chuck 210 through the first through-hole 220 a .

[0043] The first through hole 220a is provided so that foreign particles can pass through the second electrostatic chuck 220 and adhere to the first electrostatic chuck 210. Both electrostatic chucks can absorb foreign particles, which is beneficial to prolonging the working time of the parts and reducing the cleaning frequency of the parts.

[0044] Furthermore, the attraction force of the first electrostatic chuck 210 on the foreign particles is greater than the attraction force of the second electrostatic chuck 220 on the foreign particles.

[0045] As can be seen from the above, the particles used to etch the wafer are positive ions. Therefore, if the electrostatic chuck is close to the coil 130, it may attract the positive ions used for etching, thereby affecting the plasma concentration in the studio 110 and further affecting the etching of the wafer. For this reason, during the design process, the installation position of the electrostatic chuck is determined based on the attraction and attraction range of the electrostatic chuck and the attraction and attraction range of the carrier 120, so that the electrostatic chuck can be as far away from the coil 130 as possible while being able to attract impurity particles. However, if the electrostatic chuck is far away from the coil 130, the problem of weakening its attraction coverage will occur, and the electrostatic chuck may not be able to absorb impurity particles with a small splash angle and a low splash height.

[0046] A second electrostatic chuck 220 is added below the first electrostatic chuck 210. Although the second electrostatic chuck 220 is close to the coil 130 and the carrier 120, the second electrostatic chuck 220 has a smaller attraction force, while the carrier 120 has a much greater attraction force, so the second electrostatic chuck 220 hardly affects the carrier 120's attraction to positive ions. At the same time, impurity particles with a small splash angle and a low splash height are more likely to approach the second electrostatic chuck 220 and be attracted by the second electrostatic chuck 220 because of the low position of the second electrostatic chuck 220.

[0047] It should be explained that, although the attraction of the second electrostatic chuck 220 is relatively small, it can change the movement direction of the splashed impurity particles, so that the impurity particles with a small splash angle and a low splash height can continue to move upward. Since the attraction of the first electrostatic chuck 210 is greater, the impurity particles will be increasingly attracted after rising, so that the impurity particles can move further upward. Finally, some impurity particles are adsorbed on the second electrostatic chuck 220, and some impurity particles pass through the first perforation 220a and are adsorbed on the first electrostatic chuck 210.

[0048] Optionally, the second electrostatic chuck 220 is densely covered with first through holes 220 a.

[0049] Increasing the number of the first through holes 220 a and reducing the effective adsorption area of ​​the second electrostatic chuck 220 can allow as many foreign particles as possible to adhere to the first electrostatic chuck 210 .

[0050] The impurity particles are concentratedly attached to the first electrostatic chuck 210, and the impurity particles are kept away from the etching gas source (such as the third group of gas nozzles 330 described below), thereby avoiding the airflow disturbance that disturbs the impurity particles attached to the electrostatic chuck, thereby ensuring the stability and reliability of the impurity particle adsorption.

[0051] In one embodiment, the electrostatic chuck is connected to the positive electrode of the power supply to attract negatively charged impurity particles.

[0052] It is easy to understand that the impurity particles generated by the bombardment of the wafer by positively charged gas atoms are usually negatively charged. Therefore, the impurity particles present in the etching chamber during the etching process are usually negatively charged particles. The electrostatic chuck is set as a single-plate structure so that the electrostatic chuck is connected to the positive pole of the power supply. The electrostatic chuck can absorb most of the impurity particles in the etching chamber and ensure the clean environment in the etching chamber.

[0053] In another embodiment, the electrostatic chuck includes: a first electrode 211 connected to the positive electrode of the power supply and used to attract negatively charged impurity particles; a second electrode 212 connected to the negative electrode of the power supply and used to attract positively charged impurity particles.

[0054] During the etching process, the ionization environment in the etching chamber is complex, and impurity particles may also be positively charged (for example, newly generated negatively charged impurity particles continuously collide with electrons, and the electrons therein are ionized); the electrostatic chuck is set to a double-plate structure, and the two plates of the electrostatic chuck are respectively connected to the positive and negative poles of the power supply. After power is turned on, the electrostatic chuck can attract both negatively charged impurity particles and positively charged impurity particles, which is beneficial to the comprehensive cleanliness of the gas environment in the etching chamber.

[0055] Optionally, the area of ​​the first electric plate 211 is greater than the area of ​​the second electric plate 212 .

[0056] For details, please refer to Figure 2 and Figure 3 In the illustrated embodiment, the first electrostatic chuck 210 and the second electrostatic chuck 220 are both roughly disc-shaped. The disc structure can well adapt to the configuration of the traditional studio 110, cover the etching chamber to the greatest extent, and thus ensure the comprehensive adsorption of impurity particles. Furthermore, the disc is cut by a vertical line parallel to its diameter, and the cutting position is far away from its center; thus, the disc is divided into two lobes, and the areas of the two lobes are different. The smaller lobe is the second electric plate 212, and the larger lobe is the first electric plate 211.

[0057] The reason why the area of ​​the first electrode 211 is designed to be larger than the area of ​​the second electrode 212 is that the impurity particles generated by the positive ion bombardment of the wafer during the etching process are usually negatively charged, so there are more negatively charged impurity particles than positively charged impurity particles in the working chamber 110. The larger area of ​​the first electrode 211 is conducive to extending the adsorption working time of the electrostatic chuck.

[0058] Optionally, the etching device provided in the present application also includes a third electrostatic chuck 230, which is arranged in the working room 110 and between the second electrostatic chuck 220 and the carrier 120; the third electrostatic chuck 230 is provided with a second perforation 230a, and impurity particles can move toward the second electrostatic chuck 220 through the second perforation 230a; the attraction of the second electrostatic chuck 220 to the impurity particles is greater than the attraction of the third electrostatic chuck 230 to the impurity particles.

[0059] A third electrostatic chuck 230 is added below the second electrostatic chuck 220, so that the third electrostatic chuck 230 with smaller attraction is closer to the coil 130 and the carrier 120, which can make it easier to attract impurity particles with small splash angles and low splash heights to move upward, and can better prevent the electrostatic chuck from disturbing the plasma environment.

[0060] Optionally, the third electrostatic chuck 230 is densely covered with second through holes 230 a .

[0061] Increasing the number of second through holes 230 a and reducing the effective adsorption area of ​​the third electrostatic chuck 230 can allow as many foreign particles as possible to adhere to the first electrostatic chuck 210 .

[0062] Three groups of electrostatic suction cups are arranged at vertical intervals, and the attraction of the three groups of electrostatic suction cups increases from bottom to top; the impurity particles attracted by the third electrostatic suction cup 230 are increasingly attracted during the upward movement, and most of the impurity particles that are not blocked can continue to rise, and eventually pass through the second perforation 230a and the first perforation 220a, and are adsorbed by the first electrostatic suction cup 210.

[0063] Under the cooperation and step-by-step guidance of the multi-layer electrostatic chuck, the impurity particles are mainly attached to the first electrostatic chuck 210. Under the support of the second electrostatic chuck 220 and the third electrostatic chuck 230, the first electrostatic chuck 210 can be further away from the coil 130 and the carrier 120, thereby better preventing the etching gas flow from disturbing the adsorbed impurity particles.

[0064] Optionally, the diameter of the second through hole 230a is larger than the diameter of the first through hole 220a.

[0065] The second through hole 230 a has a larger aperture than the first through hole 220 a , so that more impurity particles can pass through the third electrostatic chuck 230 and move toward the second electrostatic chuck 220 .

[0066] Because the third electrostatic chuck 230 is closest to the coil 130, the etching gas source is closest to the third electrostatic chuck 230, which prevents a large number of impurity particles from adhering to the third electrostatic chuck 230, thereby preventing a large number of impurity particles from re-polluting the chamber environment when air flow disturbance occurs.

[0067] Optionally, at least a portion of the second through-holes 230a are staggered with the first through-holes 220a.

[0068] Try to avoid the second through hole 230a facing the first through hole 220a, so that the second through hole 230a and the first through hole 220a are staggered. After passing through the first through hole 220a and the second through hole 230a, even if the impurity particles fall downward, they are not likely to fall directly into the plasma environment below the electrostatic chuck.

[0069] This makes it easy for foreign particles to enter the three-layer electrostatic chuck but difficult to exit, thereby ensuring that the electrostatic chuck can reliably control foreign particles.

[0070] Optionally, the etching device provided in the present application also includes: a first power supply component for supplying power to the first electrostatic chuck 210 ; a second power supply component for supplying power to the second electrostatic chuck 220 ; and a third power supply component for supplying power to the third electrostatic chuck 230 .

[0071] In one embodiment, the first power supply assembly, the second power supply assembly and the third power supply assembly all include a power supply and a power connection piece. The power connection piece can be any component such as a connector or a wiring piece that can conveniently connect the power supply and the electrostatic suction cup to achieve electrical conduction.

[0072] The three groups of electrostatic chucks are powered by independent power supplies, and the attractive force of the electrostatic chucks can be conveniently regulated by adjusting the output voltage of the power supply.

[0073] Optionally, the output voltages of the first power supply component, the second power supply component and the third power supply component increase by 20% in sequence.

[0074] The first electrostatic suction cup 210, the second electrostatic suction cup 220 and the third electrostatic suction cup 230 are arranged in equal intervals from top to bottom in the vertical direction, and the output voltages of the first power supply component, the second power supply component and the third power supply component are decreased by 20% in sequence, which can effectively ensure the progressive adsorption of the multi-layer electrostatic suction cups.

[0075] Specifically, the third electrostatic suction cup 230 at the bottom has the smallest attraction force and is used to attract the impurity particles that are baked out and splashed in an undirected manner to move upward. The third electrostatic suction cup 230 can prevent the impurity particles from directly adhering to the cavity wall or staying in the cavity. The attraction force of the second electrostatic suction cup 220 increases by 20%; as the impurity particles move upward and gradually approach the third electrostatic suction cup 230, the attraction force they receive becomes stronger and stronger; under the strong attraction of the second electrostatic suction cup 220, the impurity particles can pass through the second perforation 230a and continue to move upward. The attraction force of the first electrostatic suction cup 210 increases by another 20%; as the impurity particles move upward and gradually approach the second electrostatic suction cup 220, the attraction force they receive becomes stronger and stronger; under the stronger attraction of the first electrostatic suction cup 210, the impurity particles can pass through the first perforation 220a and continue to move upward.

[0076] As the electrostatic chuck continuously absorbs foreign particles, the foreign particles will gradually fill up the adsorption surface of the electrostatic chuck, thereby affecting the continued operation of the electrostatic chuck; at this time, the electrostatic chuck needs to be cleaned.

[0077] In one embodiment, the electrostatic chuck is detachably disposed in the working room 110; the working room 110 is disassembled, the electrostatic chuck to be cleaned is taken out, and a new, clean electrostatic chuck is replaced, or the electrostatic chuck is cleaned and put back in place, and then the etching operation can be continued.

[0078] In another embodiment, the etching device provided in the present application further includes a gas supply component, which is used to blow air to the first electrostatic chuck 210, the second electrostatic chuck 220 and the third electrostatic chuck 230 to blow away foreign particles adhering thereto and perform a cleaning function.

[0079] Specifically, after a preset number of wafers have been etched, or after the etching operation has been continued for a preset time, the gas supply assembly is started to allow the gas to purge the electrostatic chuck, and the impurity particles can be blown off by the gas flow to restore the electrostatic chuck to a clean state. After the gas purge is completed, the gas supply assembly is closed, the air pressure in the working chamber 110 is restored, and the wafer etching operation can be performed again.

[0080] In one embodiment, the air supply assembly blows air toward the electrostatic chuck. Specifically, the air supply assembly includes an air compressor and an air pipe, the air pipe connects the air compressor and the working chamber 110, and the outlet of the air pipe faces the electrostatic chuck; a valve is provided on the air pipe. When the electrostatic chuck needs to be cleaned, the valve is opened, the air compressor is started, and air can be blown toward the electrostatic chuck through the air pipe.

[0081] Since etching needs to be performed in a vacuum environment, and etching gas needs to be introduced during the etching process and the air pressure in the studio 110 needs to be regulated in conjunction with a vacuum device, the studio 110 needs to be vacuumed again after the electrostatic chuck is cleaned with air.

[0082] In another embodiment, the gas supply assembly blows the etching gas toward the electrostatic chuck. At this time, the gas pipe of the gas supply assembly is connected to the etching gas supply device. When the electrostatic chuck needs to be cleaned, it is confirmed that the etched wafer has been taken out, and the valve on the gas pipe is opened to allow the etching gas to be blown toward the electrostatic chuck through the gas pipe. In cooperation with the exhaust device, the gas pressure in the cavity can be maintained and the impurity particles blown off can be extracted.

[0083] The present application does not limit the specific configuration of the air supply assembly.

[0084] In a specific embodiment, when the electrostatic chuck needs to be cleaned, the etching wafer is confirmed to be removed, and the electrostatic chuck is powered off to make it lose the electric field attraction; at this time, most of the impurity particles can actively fall down under the influence of their own weight. Then, the electrostatic chuck is purged with the gas supply component, which can not only ensure that the fallen impurity particles are away from the electrostatic chuck, but also promote the impurity particles still attached to the surface of the electrostatic chuck to detach from the electrostatic chuck.

[0085] In another specific embodiment, the air supply assembly includes: a first group of air nozzles 310, which connect the air supply device and the working room 110 and are arranged below the first electrostatic suction cup 210, and can blow air from bottom to top toward the first electrostatic suction cup 210; a second group of air nozzles 320, which connect the air supply device and the working room 110 and are arranged below the second electrostatic suction cup 220, and can blow air from bottom to top toward the second electrostatic suction cup 220; a third group of air nozzles 330, which connects the air supply device and the working room 110 and are arranged below the third electrostatic suction cup 230, and can blow air from bottom to top toward the third electrostatic suction cup 230.

[0086] For details, please refer to Figure 1 , Figure 4 and Figure 5In the illustrated embodiment, the studio 110 includes a base 111 and a dielectric cover 112. The inner cavity of the base 111 is connected to the inner cavity of the dielectric cover 112, and an etching chamber is formed therebetween. Three layers of electrostatic chucks are suspended on the inner top surface of the dielectric cover 112. From top to bottom, the first electrostatic chuck 210, the second electrostatic chuck 220 and the third electrostatic chuck 230 are arranged at intervals; three layers of air nozzles are arranged on the cylinder wall of the dielectric cover 112. From top to bottom, the first group of air nozzles 310, the second group of air nozzles 320 and the third group of air nozzles 330 are arranged at intervals; the first group of air nozzles 310 is arranged between the first electrostatic chuck 210 and the second electrostatic chuck 220; the second group of air nozzles 320 is arranged between the second electrostatic chuck 220 and the third electrostatic chuck 230; the third group of air nozzles 330 is arranged between the third electrostatic chuck 230 and the coil 130.

[0087] Continue to refer to Figure 1 The first group of air nozzles 310, the second group of air nozzles 320 and the third group of air nozzles 330 each include a plurality of air nozzles 311 arranged at equal intervals along the circumferential direction. The cooperation of the plurality of air nozzles 311 can purge the electrostatic chuck in multiple directions, multiple angles and multiple positions, thereby ensuring the comprehensiveness of the cleaning of the electrostatic chuck.

[0088] It is easy to understand that the impurity particles are mainly attached to the bottom surface of the electrostatic chuck facing the carrier 120, so that the airflow directly blows to the bottom surface of the electrostatic chuck, which is conducive to blowing off the impurity particles attached to the electrostatic chuck.

[0089] Specifically, the gas channel 310a in the gas nozzle 311 is extended upwardly and obliquely toward the electrostatic chuck, or the main body of the gas nozzle 311 is extended upwardly and obliquely toward the electrostatic chuck. When the gas nozzle discharges gas, the airflow can sweep the electrostatic chuck above it from bottom to top.

[0090] Optionally, the gas supply assembly also includes a direction-changing adjustment member 340, which is used to change the blowing direction of the first group of gas nozzles 310, the second group of gas nozzles 320 and / or the third group of gas nozzles 330; when the blowing direction of the first group of gas nozzles 310 changes, the first group of gas nozzles 310 can blow from top to bottom toward the second electrostatic suction cup 220; when the blowing direction of the second group of gas nozzles 320 changes, the second group of gas nozzles 320 can blow from top to bottom toward the third electrostatic suction cup 230; when the blowing direction of the third group of gas nozzles 330 changes, the third group of gas nozzles 330 can blow from top to bottom toward the working room 110, thereby realizing the supply of etching gas.

[0091] In one embodiment, a mounting hole is provided on the cavity wall of the working room 110, and the air nozzle 311 is rotatably arranged in the mounting hole; the direction-changing adjustment member 340 includes a lever 341, and the lever 341 is connected to the air nozzle. By moving the lever 341, the direction of the air nozzle can be changed, and then the air outlet direction of the air nozzle can be changed.

[0092] For details, please refer to Figure 6 In the illustrated embodiment, a mounting hole is provided on the cylinder wall of the medium cover 112, a spherical protrusion 342 is provided on the air nozzle, the spherical protrusion 342 is clamped in the mounting hole, and the air nozzle 311 is rotatably set in the mounting hole through the spherical protrusion 342.

[0093] Continue to refer to Figure 6 The left end of the air nozzle is located outside the working room 110 and is used to connect to the air supply equipment; the lever 341 is connected to the left end of the air nozzle 311.

[0094] Combined with reference Figure 7 , push the lever 341 downward, and the air nozzle 311 can extend from left to right and upward; at this time, the gas blown out through the air nozzle 311 can blow from bottom to top toward the bottom surface of the electrostatic chuck.

[0095] Combined with reference Figure 8 , by pushing the lever 341 upward, the air nozzle 311 can extend from left to right and downward; at this time, the gas blown out through the air nozzle 311 can be blown from top to bottom toward the top surface of the electrostatic suction cup, or blown toward the carrier 130.

[0096] Avoid air leakage from the mounting holes. Figures 6 to 8 In the illustrated embodiment, the direction-changing adjusting member 340 further includes a bellows 343, one end of which is sealedly connected to the cavity wall of the working chamber 110, and the other end of which is sealedly connected to the air nozzle 311. Since the bellows 343 has the characteristics of deformation under force and recovery under force unloading, the bellows 343 can prevent air leakage from the mounting hole and can also adapt to the direction-changing deformation of the air nozzle 311.

[0097] To define the position of the air nozzle 311, Figures 6 to 8 In the illustrated embodiment, an arc-shaped groove 110a is provided on the hole wall of the mounting hole, and the arc-shaped groove 110a is used to fit the spherical protrusion 342; when the air nozzle 311 is arranged in the mounting hole, the spherical protrusion 342 is restricted in the arc-shaped groove 110a, and the outer spherical surface of the spherical protrusion 342 is in contact with the inner concave surface of the arc-shaped groove 110a; the arc-shaped groove 110a can not only limit the position of the spherical protrusion 342, but also continue to accommodate the spherical protrusion 342 when the air nozzle 311 changes direction, thereby playing a guiding and limiting role.

[0098] Optionally, a circle of arc-shaped grooves 110a is provided on the hole wall of the mounting hole; in this case, the air nozzle 311 can swing freely around its axial center axis, and the direction of the air nozzle 311 is more diverse.

[0099] Optionally, the upper hole wall of the mounting hole is provided with an arc groove 110a, and the lower hole wall is also provided with an arc groove 110a, and the two arc grooves 110a are symmetrically arranged; when the air nozzle 311 is arranged in the mounting hole, the upper part of the spherical protrusion 342 is limited by the upper arc groove 110a, and the lower part is limited by the lower arc groove 110a; the two arc grooves 110a cooperate to clamp the spherical protrusion 342, and the spherical protrusion 342 can only move vertically under the limitation of the arc groove 110a. At this time, the air nozzle 311 can only swing upward or downward. Limiting the swing direction of the air nozzle 311 can prevent the air nozzle 311 from being moved to an unwanted direction due to operational errors.

[0100] In order to improve the stability of the air nozzle 311 after changing direction, a first spring piece 344 and a second spring piece 345 are provided in the mounting hole. The first spring piece 344 can press against the air nozzle from top to bottom, and the second spring piece 345 can press against the air nozzle from bottom to top. The first spring piece 344 and the second spring piece 345 have elastic characteristics, will deform when under pressure, and have a tendency to return to their original state.

[0101] For details, please refer to Figure 6 In the illustrated embodiment, the first spring piece 344 is arranged at the top of the mounting hole, and the second spring piece 345 is arranged at the bottom of the mounting hole; when the air nozzle 311 is in a horizontal state, the first spring piece 344 and the second spring piece 345 are both in a compressed state, the first spring piece 344 presses the air nozzle 311 downward, and the second spring piece 345 presses the air nozzle upward, so that the air nozzle 311 is in a balanced state as a whole.

[0102] Combined with reference Figure 7 After the lever 341 is pushed downward, the right end of the air nozzle 311 swings upward; at this time, the first elastic sheet 344 is further deformed, and the second elastic sheet 345 stretches upward and maintains the state of abutting the air nozzle 311. The forces of the first elastic sheet 344 and the second elastic sheet 345 interact with each other, so that the air nozzle 311 is in a balanced state again.

[0103] Combined with reference Figure 8 After the lever 341 is pushed upward, the right end of the air nozzle 311 swings downward; at this time, the second elastic sheet 345 is further deformed, while the first elastic sheet 344 stretches downward and maintains the state of abutting the air nozzle 311. The forces of the first elastic sheet 344 and the second elastic sheet 345 interact with each other, so that the air nozzle 311 is in a balanced state again.

[0104] By symmetrically arranging the first spring piece 344 and the second spring piece 345 along the vertical direction, when the air nozzle 311 swings upward or downward and changes direction, the spring piece can adapt through its own deformation and provide reliable supporting force for the air nozzle 311, so as to improve the state stability of the air nozzle 311 after the change of direction, thereby ensuring the air outlet stability of the air nozzle 311.

[0105] In another embodiment, the direction-changing adjustment member 340 includes a direction-changing driving member 346, which can be any driving member such as a cylinder or an electric cylinder that can drive the air nozzle 311 to swing in the mounting hole; the direction-changing driving member 341 is connected to the air nozzle 311 and can change the blowing direction of the air nozzle 311 by driving the air nozzle 311 to swing vertically.

[0106] For details, please refer to Fig. 9 In the illustrated embodiment, the direction-changing adjusting member 340 further includes an annular air pipe 347, which is connected to the etching gas supply device; a group of air nozzles ( Fig. 9 The third group of air nozzles 330 are connected in series through an annular air pipe 347, and the air supply device can simultaneously supply air to multiple air nozzles in one group through the annular air pipe 347. The annular air pipe 347 is made of a rigid material (such as metal), and the direction-changing drive member 346 is connected to the annular air pipe 347.

[0107] Any air nozzle 311 is swingably arranged in a corresponding mounting hole through a ball bearing, a spherical protrusion, a rotating shaft or the like.

[0108] Continue to refer to Fig. 9 When the direction-changing driving member 346 drives the annular air pipe 347 to move vertically upward, the end of the air nozzle 311 used for air outlet swings downward, and the air nozzle 311 can blow air from top to bottom; when the direction-changing driving member 346 drives the annular air pipe 347 to move vertically downward, the end of the air nozzle 311 used for air outlet swings upward, and the air nozzle 311 can blow air from bottom to top.

[0109] The present application does not limit the specific configuration of the direction-changing adjustment member 340 .

[0110] By setting the reversing adjustment member 340, the blowing direction of the air nozzle 311 is adjustable. In a specific embodiment, three layers of electrostatic suction cups are provided in the working room 110, and a group of air nozzles are provided under each layer of electrostatic suction cups; the air nozzles purge the electrostatic suction cups through jets to remove the impurity particles on the electrostatic suction cups. During the cleaning process, the three groups of air nozzles first blow from bottom to top to purge the bottom surface of the electrostatic suction cups, which are mainly used to adsorb impurity particles; after the preset blowing time, the three groups of air nozzles are changed to blow from top to bottom through the reversing adjustment member 340. At this time, the airflow can both blow away the impurity particles that fall on the lower electrostatic suction cup and promote the impurity particles to move to the lower air outlet channel. If necessary, the blowing direction of the air nozzle 311 can be changed multiple times during the cleaning process to continuously purify the gas environment in the cavity through changes in airflow.

[0111] In another specific embodiment, the direction-changing adjustment member 340 is only used to change the blowing direction of the third group of gas nozzles 330 arranged at the bottom layer. When cleaning the electrostatic chuck, the gas outlet direction of the third group of gas nozzles 330 is tilted upward to facilitate the airflow to sweep the second group of electrostatic chucks 320; during the etching operation, the gas outlet direction of the third group of gas nozzles 330 is tilted downward. At this time, the third group of gas nozzles 330 blows etching gas toward the area surrounded by the coil 130. Since the third group of gas nozzles 330 are close to the coil 130, the etching gas blown into the etching chamber can be quickly and fully affected by the alternating magnetic field of the coil 130, thereby ensuring the concentration of plasma and improving the etching efficiency of the wafer.

[0112] Optionally, the attraction of the carrier 120 to the charged particles is greater than the attraction of the first electrostatic chuck 210 and the second electrostatic chuck 220 to the charged particles.

[0113] In one embodiment, the coil 130 is powered by a first RF power supply with a frequency of 400 kHz, the carrier 120 is powered by a second RF power supply with a frequency of 13.56 MHz, and the first electrostatic chuck 210 and the second electrostatic chuck 220 are powered by low voltage (eg, 5-10 V) DC power.

[0114] This makes the attraction of the carrier 120 stronger, and can prevent the electric field force of the electrostatic chuck from affecting the concentration of plasma and the bombardment of the plasma on the wafer.

[0115] Optionally, the medium cover 112 includes: a barrel 112b, which is arranged in a cylindrical shape, with the upper and lower ends of the barrel 112b open, and the lower end of the barrel 112b is connected to the base 111; a cover 112a, which is used to seal the upper end of the barrel 112b; the hierarchical electrostatic adsorption etching device also includes a bracket 140, and the bracket 140 is used to arrange the first electrostatic suction cup 210 and the second electrostatic suction cup 220 in layers; the bracket 140 is arranged on the cover 112a, and when the cover 112a is connected to the barrel 112b, the bracket 140 is hoisted in the medium cover 112.

[0116] For details, please refer to Figure 4 and Figure 5 In the illustrated embodiment, the barrel 112b is cylindrical and made of ceramic, and the coil 130 is wound around the barrel 112b; the cover 112a is disc-shaped and sealed with the barrel 112b. The bracket 140 is disposed in the dielectric cover 112 and hoisted on the cover 112a.

[0117] Combined with reference Figure 2 and Figure 3 The bracket 140 includes a plurality of brackets, any of which is provided with a three-level support platform, and the plurality of brackets are arranged on the cover portion 112a at intervals along the circumferential direction and can cooperate to support the first electrostatic suction cup 210, the second electrostatic suction cup 220 and the third electrostatic suction cup 230.

[0118] Optionally, the barrel portion 112b is detachably connected to the cover portion 112a.

[0119] In one embodiment, an insert block is provided on one of the barrel portion 112b and the cover portion 112a, and an insert hole is provided on the other, so that the barrel portion 112b and the cover portion 112a can be connected by inserting the insert block into the insert hole, and the connection between the barrel portion 112b and the cover portion 112a can be released by detaching the insert block from the insert hole.

[0120] In another embodiment, the barrel 112b and the cover 112a are tightly matched. For example, the cover 112a is provided with an outer rim, and the barrel 112b can be inserted into the outer rim of the cover 112a, thereby realizing the connection between the barrel 112b and the cover 112a; the connection between the barrel 112b and the cover 112a can be easily released by removing the cover 112a.

[0121] The present application does not limit the detachable connection method between the barrel portion 112b and the cover portion 112a.

[0122] The barrel 112b and the cover 112a are detachably connected, and when the electrostatic chuck needs to be cleaned or replaced, the cover 112a can be easily removed to operate the bracket 140 and the electrostatic chuck. After the electrostatic chuck is processed, the cover 112a is reinstalled to conveniently restore the etching device.

[0123] Optionally, the bracket 140 includes a plurality of brackets, and at least some of the brackets are detachably disposed on the cover portion 112a.

[0124] In one embodiment, the bracket and the cover 112a are connected by magnetic attraction. For example, a magnet is provided on one of the bracket and the cover 112a, and a metal material is provided on the other. The bracket and the cover 112a can be connected by the magnet adsorbing the metal; the connection between the bracket and the cover 112a can be released by overcoming the magnetic force of the magnet.

[0125] In another embodiment, a socket is provided on the cover 112a, and a bracket is used to connect to the upper end of the cover 112a and is provided with a horizontal or hook-shaped plug board; the bracket and the cover 112a can be connected by inserting the plug board into the socket; the connection between the bracket and the cover 112a can be released by removing the plug board from the socket.

[0126] The present application also does not limit the detachable connection method between the bracket and the cover 112a.

[0127] At least a portion of the bracket and the cover 112 a are detachably connected, and a portion of the bracket can be removed to facilitate taking out the electrostatic chuck from the bracket 140 or installing the electrostatic chuck into the bracket 140 .

[0128] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A hierarchical electrostatic adsorption etching device, characterized in that: include: A working room (110), used to provide a space for wafer etching; A carrier (120) is disposed in the working room (110) and is used to receive a wafer; A first electrostatic chuck (210) is disposed in the working chamber (110) and above the carrier (120); A second electrostatic chuck (220) is disposed in the working chamber (110) and between the first electrostatic chuck (210) and the carrier (120); During the etching process, the first electrostatic chuck (210) and the second electrostatic chuck (220) are powered, have electric field attraction, and are capable of attracting impurity particles to adhere; The second electrostatic chuck (220) is provided with a first through-hole (220a), and foreign particles can move toward the first electrostatic chuck (210) through the first through-hole (220a); The attraction force of the first electrostatic chuck (210) is greater than the attraction force of the second electrostatic chuck (220).

2. The hierarchical electrostatic adsorption etching device according to claim 1, characterized in that: The first electrostatic chuck (210) and / or the second electrostatic chuck (220) comprises: A first electric plate (211), connected to the positive electrode of the power source, for attracting negatively charged impurity particles; A second electric plate (212), connected to the negative electrode of the power source, for attracting positively charged impurity particles; The area of ​​the first electric plate (211) is greater than the area of ​​the second electric plate (212).

3. The hierarchical electrostatic adsorption etching device according to claim 1 or 2, characterized in that: It also includes a third electrostatic chuck (230), wherein the third electrostatic chuck (230) is disposed in the working room (110) and between the second electrostatic chuck (220) and the carrier (120); The third electrostatic chuck (230) is provided with a second through-hole (230a), and foreign particles can move toward the second electrostatic chuck (220) through the second through-hole (230a); The attraction force of the second electrostatic chuck (220) is greater than the attraction force of the third electrostatic chuck (230).

4. The hierarchical electrostatic adsorption etching device according to claim 3, characterized in that: Also includes: A first power supply component, used to supply power to the first electrostatic chuck (210); A second power supply component, used to supply power to the second electrostatic chuck (220); A third power supply component, used to supply power to the third electrostatic chuck (230) Among them, the output voltages of the first power supply component, the second power supply component and the third power supply component increase by 20% respectively.

5. The hierarchical electrostatic adsorption etching device according to claim 3, characterized in that: The diameter of the second through hole (230a) is larger than the diameter of the first through hole (220a); And / or, at least a portion of the second through-holes (230a) are staggered with the first through-holes (220a).

6. The hierarchical electrostatic adsorption etching device according to claim 3, characterized in that: It also includes an air supply component, which is used to blow air to the first electrostatic chuck (210), the second electrostatic chuck (220) and the third electrostatic chuck (230) so as to blow away foreign particles adhering thereto and achieve a cleaning effect.

7. The hierarchical electrostatic adsorption etching device according to claim 6, characterized in that: The gas supply assembly comprises: a first set of air nozzles (310), connected to the air supply device and the working chamber (110), and disposed below the first electrostatic chuck (210), capable of blowing air from bottom to top toward the first electrostatic chuck (210); a second set of air nozzles (320), connected to the air supply device and the working chamber (110), and disposed below the second electrostatic chuck (220), capable of blowing air from bottom to top toward the second electrostatic chuck (220); The third group of air nozzles (330) is connected to the air supply device and the working chamber (110), and is disposed below the third electrostatic chuck (230), and is capable of blowing air from bottom to top toward the third electrostatic chuck (230).

8. The hierarchical electrostatic adsorption etching device according to claim 7, characterized in that: The air supply assembly further comprises a direction-changing adjustment member (340), wherein the direction-changing adjustment member (340) is used to change the blowing direction of the first group of air nozzles (310), the second group of air nozzles (320) and / or the third group of air nozzles (330); When the blowing direction of the first group of air nozzles (310) changes, the first group of air nozzles (310) can blow air from top to bottom toward the second electrostatic chuck (220); When the blowing direction of the second group of air nozzles (320) changes, the second group of air nozzles (320) can blow air from top to bottom toward the third electrostatic chuck (230); When the blowing direction of the third group of gas nozzles (330) is changed, the third group of gas nozzles (330) can blow gas from top to bottom into the working chamber (110), thereby achieving the supply of etching gas.

9. The hierarchical electrostatic adsorption etching device according to claim 1, characterized in that: The studio (110) comprises: A base (111), the carrier (120) being arranged in the base (111), and a wafer inlet and outlet being arranged on one side of the base (111); A medium cover (112), disposed on the base (111) and sealedly connected to the base (111); The hierarchical electrostatic adsorption etching device further comprises a coil (130), the coil (130) being wound outside the dielectric cover (112), and the first electrostatic chuck (210) and the second electrostatic chuck (220) being located at a position higher than the coil (130); During the etching process, the coil (130) is powered on and can ionize the etching gas to generate plasma, and the carrier (120) is powered on and generates a negative bias potential to attract positive ions to bombard the wafer; The attraction of the carrier (120) to the charged particles is greater than the attraction of the first electrostatic chuck (210) and the second electrostatic chuck (220) to the charged particles.

10. The hierarchical electrostatic adsorption etching device according to claim 9, characterized in that: The medium cover (112) comprises: The barrel (112b) is provided in a cylindrical shape, the upper and lower ends of the barrel (112b) are open, and the lower end of the barrel (112b) is connected to the base (111); A cover portion (112a) used for sealing the upper end of the cylinder portion (112b); The hierarchical electrostatic adsorption etching device further comprises a bracket (140), wherein the bracket (140) is used to arrange the first electrostatic chuck (210) and the second electrostatic chuck (220) in layers; The bracket (140) is arranged on the cover portion (112a); when the cover portion (112a) is connected to the cylinder portion (112b), the bracket (140) is hoisted in the medium cover (112).

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