ICP and CCP combined plasma etching device and method and preparation method

Abstract

The invention provides an ICP and CCP combined plasma etching device and method and a preparation method. The device comprises an upper electrode and a lower electrode which are oppositely arranged in a plasma vacuum reaction cavity; the upper electrode comprises a gas spraying area used for spraying gas downwards and an edge area surrounding the gas spraying area, a plurality of windows evenly distributed in the circumferential direction are formed in the edge area, and each window is sealed by an insulating part; wherein coils are arranged above the insulating parts in a one-to-one correspondence mode, or coils which extend in the circumferential direction of the edge area and pass through the upper portions of all the insulating parts are arranged above the edge area. The problems that an existing ICP etching device cannot bear a high-power bias electric field, and a CCP etching device is prone to causing relatively low plasma density at the edge of a substrate can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of plasma etching, and particularly to a plasma etching device, method and preparation method combining ICP and CCP. Background Art

[0002] Currently, since the dry etching process using plasma for etching can effectively control the size of the etching opening, it has become the mainstream etching process. In existing semiconductor etching devices, radio frequency signals are usually used to form plasma, and a bias voltage is formed on the substrate to be processed by the radio frequency signal, so that the plasma can bombard the substrate to be processed, thereby realizing the etching of the substrate to be processed.

[0003] Existing etching devices using radio frequency signals to form plasma mainly include inductively coupled plasma (ICP) etching devices, capacitively coupled plasma (CCP) etching devices, electron cyclotron resonance (ECR) etching devices, etc. Among them, inductively coupled plasma (ICP) etching devices and capacitively coupled plasma (CCP) etching devices have been widely used in the field of dry etching due to their simple structure and relatively low cost.

[0004] However, for an ICP etching device, it only has a lower electrode and no upper electrode, thus limiting the feeding of a high-power bias power source (because the lack of a grounding electrode in ICP leads to poor grounding and inability to withstand a high-power bias electric field), so it is difficult to complete the etching of high aspect ratio trenches; for a CCP etching device, it is prone to the problem that the plasma density at the edge of the substrate is relatively low, affecting the etching uniformity of the substrate. Summary of the Invention

[0005] Aiming at the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a plasma etching device, method and preparation method combining ICP and CCP to solve the problems that the existing ICP etching device cannot withstand a high-power bias electric field and the CCP etching device is prone to relatively low plasma density at the edge of the substrate.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] In the first aspect, the present invention provides a plasma etching device combining ICP and CCP, including an upper electrode and a lower electrode oppositely arranged at the top and bottom of a plasma vacuum reaction chamber;

[0008] The upper electrode includes a gas spraying area for spraying gas downward and an edge area surrounding the gas spraying area. The edge area is provided with a plurality of windows evenly distributed in the circumferential direction, and each of the windows is closed by an insulating member;

[0009] Among them, coils are respectively disposed on each of the insulating members, or a coil extending along the circumferential direction of the edge region and passing above all of the insulating members is disposed on the edge region.

[0010] Further, the insulating member includes a filling portion, and the filling portion includes a first horizontal plate and a convex platform longitudinally extending from the first horizontal plate. The first horizontal plate abuts and is fixed to the surface of the upper electrode, and the convex platform is filled in the corresponding window to seal the corresponding window.

[0011] Further, the insulating member further includes a ferrule joint, and the ferrule joint includes a second horizontal plate and a card slot longitudinally extending from the second horizontal plate. The second horizontal plate and the first horizontal plate abut and are fixed to the opposite surfaces of the upper electrode, and the card slot is installed in the corresponding window for the convex platform to be clamped in the card slot.

[0012] Further, the device further includes an electrostatic chuck disposed above the lower electrode for fixing a substrate to be processed;

[0013] A thermal regulation element is further disposed on the bottom surface of the electrostatic chuck, and the thermal regulation element is divided into a plurality of temperature regulation regions radially distributed;

[0014] A temperature sensor and a circumferentially extending flow channel are respectively disposed in each of the temperature regulation regions. Each of the flow channels is communicated with a cooling fluid source through a first valve and is communicated with a heating fluid source through a second valve;

[0015] Each of the first valves, second valves and temperature sensors is connected to a controller, and the controller is used to adjust the opening degrees of the corresponding first valves and second valves according to the difference between the measured value of each temperature sensor and the target temperature of the corresponding temperature regulation region.

[0016] Further, the coil is connected to a first radio frequency power source, the upper electrode is grounded, and the lower electrode is connected to a second radio frequency power source and a bias power source.

[0017] Further, the frequencies of the first radio frequency power source, the second radio frequency power source and the bias power source are 400 KHz - 100 MHz.

[0018] Further, the area of the gas spraying region is greater than 80% of the substrate to be processed.

[0019] Further, the insulating member is made of a ceramic or glass material.

[0020] Further, the window is circular or substantially square.

[0021] In a second aspect, the present invention provides a plasma etching method, including:

[0022] Obtain a substrate to be processed;

[0023] Fix the substrate to be processed above the lower electrode in the plasma etching device as described above, so as to etch the substrate to be processed through the plasma etching device. During the etching process, the coil is connected to a first radio frequency power source, and one of the upper electrode and the lower electrode is grounded, and the other is connected to a second radio frequency power source.

[0024] In a third aspect, the present invention provides a method for manufacturing a plasma etching device, including:

[0025] Provide a plasma vacuum reaction chamber;

[0026] Provide an upper electrode and a lower electrode. The upper electrode includes a gas spraying area for spraying gas downward and an edge area surrounding the gas spraying area;

[0027] Open a plurality of windows evenly distributed in the circumferential direction in the edge area;

[0028] Arrange insulating members in each of the windows to close each of the windows;

[0029] Dispose the upper electrode and the lower electrode opposite to each other at the top and bottom of the plasma vacuum reaction chamber;

[0030] Arrange coils on each of the insulating members in a one-to-one correspondence, or arrange a coil on the edge area that extends along the circumferential direction of the edge area and passes above all the insulating members.

[0031] By adopting the above technical solutions, the present invention has the following beneficial effects:

[0032] The present invention organically combines the structures of ICP and CCP. By providing an upper electrode, one of the upper electrode and the lower electrode can be grounded, thereby solving the problem that the ICP etching device has poor grounding and cannot withstand a high-power bias electric field; by evenly opening a plurality of windows in the circumferential direction in the edge area of the upper electrode and respectively arranging insulating members in each window to form a dielectric window, the magnetic field generated by the upper coil loaded with a radio frequency power source can pass through the dielectric window, and due to the Faraday cage principle, the electric field below the dielectric window cannot penetrate upward, thereby generating more plasma at the edge of the substrate and solving the problem of uneven plasma etching caused by low plasma density at the edge of the substrate. Thus, the present invention combines the respective advantages of ICP and CCP in the same chamber, and isolates the interference between ICP and CCP through the method of grounding the upper electrode + Faraday cage, can form a strong magnetic field and electric field in the reaction chamber, improves the etching efficiency, alleviates the problem of uneven edge etching, and has a simple structure and low cost, which is beneficial to large-scale application in the semiconductor industry. Description of the Drawings

[0033] Figure 1 is a schematic structural diagram of a traditional ICP etching device;

[0034] Figure 2 is a schematic structural diagram of a traditional CCP etching device;

[0035] Figure 3 is a schematic structural diagram of the ICP and CCP combined plasma etching device according to Embodiment 1 of the present invention;

[0036] Figure 4 is a top view of the ICP and CCP combined plasma etching device according to Embodiment 1 of the present invention;

[0037] Figure 5 is a top view of the ICP and CCP combined plasma etching device according to Embodiment 2 of the present invention;

[0038] Figure 6 is a schematic structural diagram of the ICP and CCP combined plasma etching device according to Embodiment 3 of the present invention;

[0039] Figure 7 is a schematic structural diagram of the ICP and CCP combined plasma etching device according to Embodiment 4 of the present invention;

[0040] Figure 8 is a schematic diagram of the temperature adjustment area division of the thermal adjustment element in Embodiment 4 of the present invention. Detailed implementation manners

[0041] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The singular forms "a", "the" and "said" used in the present disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0043] A traditional ICP etching device such as Figure 1As shown, it mainly includes a dielectric window 10', a coil 30' and an electrode 20'. Among them, the coil 30' is arranged above the dielectric window 10' and connected to a radio frequency power source, and the electrode 20' is used to carry the substrate to be processed (such as a wafer). When etching is required, the radio frequency power source is loaded onto the coil 30', and the coil 30' generates an alternating magnetic field, which in turn forms an electromagnetic induction electric field in the reaction chamber. This electric field causes the electrons in the gas to be accelerated and generate energy, thereby triggering ionization and the formation of plasma. Then, by providing a bias electric field for the plasma through a bias power supply, the etching of the substrate to be processed can be achieved. However, due to the absence of a grounded electrode, the ICP etching device cannot withstand the bombardment of a high-power bias electric field, so it is difficult to complete the etching of deep trenches with a high aspect ratio.

[0044] Traditional CCP etching devices such as Figure 2 As shown, it mainly includes an upper electrode 10” and a lower electrode 20” oppositely arranged in the reaction chamber. When a radio frequency power source is loaded, a high-frequency electric field will be generated between the electrodes 10” and 20”. Gas molecules are excited and ionized in this electric field to form plasma. Then, by providing a bias electric field for the plasma through a bias power supply, the etching of the substrate to be processed can be achieved. However, the CCP etching device is prone to the problem of low plasma density at the edge of the substrate, which affects the etching uniformity.

[0045] Based on this, the present invention provides a plasma etching device combining ICP and CCP to solve the problems that the existing ICP etching device cannot withstand a high-power bias electric field and the CCP etching device is prone to relatively low plasma density at the edge of the substrate.

[0046] Embodiment 1

[0047] As Figure 3 and Figure 4 As shown, this embodiment provides a plasma etching device combining ICP and CCP, which mainly includes an upper electrode 10, a lower electrode 20 and a coil 30. Among them, both the upper electrode 10 and the lower electrode 20 are circular electrode plates, which are coaxially and oppositely arranged in the plasma vacuum reaction chamber. During etching, the substrate to be processed (not shown) is placed above the lower electrode 20. This substrate to be processed can be, for example, a silicon wafer, a gallium arsenide wafer or an indium phosphide wafer, etc.

[0048] Referring again to Figure 3 and Figure 4 As shown, the upper electrode 10 in this embodiment includes a circular gas spraying area S1 in the central region and an annular edge area S2 surrounding the gas spraying area S1. Among them, the gas spraying area S1 is used to spray gas downward, and the gas spraying area S1 and the edge area S2 can be made of the same material or different materials; the thicknesses of the gas spraying area S1 and the edge area S2 can be the same or different, and this embodiment does not make any specific restrictions on this.

[0049] Different from the traditional CCP etching device, in this embodiment, a plurality of hollowed windows 11 are circumferentially and uniformly formed along the edge region S2 of the upper electrode 10 (as Figure 1 shown, the windows 11 are specifically formed as through holes extending longitudinally), and each window 11 is respectively closed by an insulating member 12 to form a dielectric window. Among them, cylindrical coils 30 are disposed one by one above each insulating member 12, and the radius of the coil 30 is smaller than the radius of the corresponding window 11 and is coaxially arranged with the corresponding window 11.

[0050] Specifically, as Figure 4 shown, in the edge region S2 of the upper electrode 10, a plurality of circular windows 11 are circumferentially and uniformly formed. At each window 11, a cylindrically shaped insulating member 12 with a matching shape is embedded to form a dielectric window, and 1 - 2 turns of coils 30 (the coils 30 at each location should be the same) coaxially arranged with the corresponding window 11 are respectively disposed above each insulating member 12. When the coil 30 is loaded with a radio frequency power source, the magnetic field generated by it can pass through the dielectric window to generate plasma in the reaction chamber, thereby enhancing the plasma density at the edge of the substrate; at the same time, based on the Faraday cage principle, the electric field generated in the reaction chamber cannot penetrate the dielectric window, thereby ensuring the electric field strength in the reaction chamber.

[0051] Thus, this embodiment organically combines the structures of ICP and CCP. By providing the upper electrode 10, it can be used for grounding, and can solve the problems of poor grounding of the ICP etching device and inability to withstand high - power bias electric fields; at the same time, by circumferentially and uniformly forming a plurality of windows 11 along the edge region S2 of the upper electrode 10 and respectively providing insulating members 12 at each window 11 to form a dielectric window, the magnetic field generated by loading the radio frequency power source on the coil 30 above the dielectric window can pass through the dielectric window, while the electric field below the dielectric window cannot penetrate upward, thereby solving the problem of uneven etching caused by low plasma density at the edge of the substrate. It can be seen that this embodiment can form a strong magnetic field and electric field in the reaction chamber. The combination of the metal plate and the dielectric window can adjust the electric field, U value, and plasma density, improve the etching efficiency, alleviate the problem of uneven edge etching, and has a simple structure and low cost, which is conducive to large - scale application in the semiconductor industry.

[0052] When the plasma etching device of this embodiment is in use, the coil 30 is connected to a first radio frequency power source, the upper electrode 10 is grounded, and the lower electrode 20 can be connected to multiple radio frequency power sources, including a second radio frequency power source and a bias power source. Among them, the radio frequency signal generated by the first radio frequency power source generates a magnetic field through the coil 30; the radio frequency signal generated by the second radio frequency power source ionizes the gas in the reaction chamber through the capacitance formed by the upper electrode 10 and the lower electrode 20; the bias power source forms a bias voltage on the substrate to be processed on the upper surface of the lower electrode 20 to achieve etching of the substrate to be processed.

[0053] In a preferred embodiment, the frequencies of the first radio frequency power source, the second radio frequency power source, and the bias power source are all 400 KHz - 100 MHz.

[0054] In a preferred embodiment, a seal (not shown) may also be provided between the insulating member 12 and the window 11 to improve the sealing performance between the insulating member 12 and the window 11.

[0055] Referring again to Figure 3 As shown, a gas buffer chamber 13 is formed above the gas spraying area S1 of the upper electrode 10. The gas buffer chamber 13 is communicated with an external gas supply device (not shown) to supply reaction gas through the external gas supply device. The reaction gas may be one or a mixture of Cl 2 , BCl 3 , Ar, N 2 . At the same time, a plurality of air inlet holes 14 communicating with the gas buffer chamber 13 are uniformly arranged in the gas spraying area S1, so that the reaction gas in the gas buffer chamber 13 can enter the reaction chamber through these air inlet holes 14 and generate plasma under the action of a magnetic field and an electric field. Preferably, the area of the gas spraying area S1 is greater than 80% of the area of the substrate to be processed.

[0056] In addition, as Figure 3 shown, the plasma etching device of this embodiment may further include a cavity lining 40 for protecting the inner wall of the reaction chamber.

[0057] It should be understood that the insulating member 12 in this embodiment can be made of any suitable insulating material such as ceramics or glass, and the present invention does not make any specific limitations in this regard.

[0058] Embodiment 2

[0059] This embodiment provides a plasma etching device combining ICP and CCP. As Figure 5 shown, different from Embodiment 1, in this embodiment, a plurality of substantially square windows 11 are uniformly opened along the circumference in the edge area S2 of the upper electrode 10. The length direction of each window 11 extends along the radial direction of the upper electrode 10 and is respectively closed by an insulating member 12 to form a dielectric window. One or two cylindrical coils 30 extending along the circumference and passing above all the insulating members 12 are arranged above the edge area S2. The coil 30 is preferably arranged above the center of each window 11.

[0060] When the coil 30 is loaded with a radio frequency power source, the magnetic field generated by it can pass through the dielectric window to generate plasma in the reaction chamber, thereby enhancing the plasma density at the edge of the substrate; at the same time, based on the Faraday cage principle, the electric field generated in the reaction chamber cannot penetrate the dielectric window, thus ensuring the electric field strength in the reaction chamber.

[0061] It should be understood that in addition to being configured in a circular or substantially square shape as shown in Figure 4 , Figure 5 , the window 11 in this embodiment can also be configured in any other suitable shape, and this embodiment does not impose any specific restrictions on this.

[0062] Embodiment 3

[0063] Based on Embodiments 1 and 2, this embodiment provides another implementation manner of the insulating member 12. Specifically, as shown in Figure 6 , the insulating member 12 in this embodiment includes a filling portion 121, and the filling portion 121 includes a first transverse plate 1211 and a boss 1212 longitudinally extending from the center of the first transverse plate 1211. Among them, the first transverse plate 1211 abuts and is fixed to the surface of the upper electrode 10, and the boss 1212 is filled in the corresponding window 11 to achieve the sealing of the corresponding window 11. By way of example and not limitation, the first transverse plate 1211 is circular, and the boss 1212 is cylindrical.

[0064] In addition, the insulating member 12 in this embodiment may further include a ferrule joint 122, and the ferrule joint 122 includes a second transverse plate 1221 and a card slot 1222 longitudinally extending from the center of the second transverse plate 1221. During installation, the second transverse plate 1221 and the first transverse plate 1211 abut and are fixed to the opposite surfaces of the upper electrode 10, the card slot 1222 is installed in the corresponding window 11 and its outer wall is in sealing fit with the hole wall of the window 11, and the boss 1212 is clamped in the card slot 1222. By way of example and not limitation, the second transverse plate 1212 is circular, the card slot 1222 is cylindrical, and a sealing member may be provided between the first transverse plate 1211 and / or the second transverse plate 1221 and the surface of the upper electrode 10.

[0065] Embodiment 4

[0066] As shown in Figure 7 , this embodiment preferably uses an electrostatic chuck 50 to fix the substrate to be processed above the lower electrode 20. During the etching process of the substrate, the plasma gas reaction ions and the materials on the surface of the substrate will undergo a chemical reaction, and the local substrate temperature and the chemical reaction ratio on the substrate are interrelated.

[0067] During the plasma etching process of a multi-layer substrate, it may occur that the etching of one layer requires the central area to be hotter than the edge area, but the etching of another layer requires the central area to be colder than the edge area. In this way, the etching device needs to have the ability to control the temperature distribution of the substrate from the center to the edge. For this reason, a circular thermal adjustment element 60 is added to the bottom of the electrostatic chuck 50 in this embodiment to improve the control of the radial temperature of the substrate, so as to achieve an ideal substrate temperature distribution.

[0068] In this embodiment, the substrate to be processed, the electrostatic chuck 50, the thermal adjustment element 60 and the lower electrode 20 are coaxially arranged. Figure 8 As shown, the heat regulating element 50 is divided into a plurality of temperature regulating areas distributed radially (seven areas Z1 to Z7 are exemplarily divided in the figure, but the present embodiment does not impose any restriction on the number of high-temperature areas), and the plurality of temperature regulating areas surround the center of the heat regulating element 60 from the inside to the outside in sequence. Among them, each temperature regulating area is provided with a circumferentially extending flow channel (not shown), and each flow channel is connected to a cooling fluid source (not shown) through a first valve (not shown), and is connected to a heating fluid source (not shown) through a second valve (not shown).

[0069] When the first valve is opened and the second valve is closed, the cooling fluid source provides cooling liquid to the corresponding flow channel to remove heat from the corresponding area of ​​the substrate during the processing process. The cooling fluid flows through the corresponding flow channel and then flows back to the cooling fluid source for recycling.

[0070] When the second valve is opened and the first valve is closed, the heating fluid source provides hot fluid to the corresponding flow channel to heat the corresponding area of ​​the substrate. The hot fluid flows through the corresponding flow channel and then flows back to the heating fluid source for recycling.

[0071] In this embodiment, each temperature adjustment area is also provided with a corresponding temperature sensor (not shown) to measure the temperature of the corresponding area. Each temperature sensor and each first valve and second valve are connected to a controller (not shown), so that the controller can adjust the opening of the corresponding first valve and second valve according to the difference between the measured value of each temperature sensor and the target temperature of the corresponding area, thereby realizing independent adjustment of the temperature of different areas of the substrate to be processed and achieving an ideal substrate temperature distribution.

[0072] Preferably, a heat insulating layer (not shown) is provided between each flow channel to isolate heat transfer between different flow channels and avoid mutual influence.

[0073] Example 5

[0074] This embodiment provides a plasma etching method, which specifically includes the following steps:

[0075] S11, obtaining a substrate to be processed, which may be, for example, a silicon wafer, a gallium arsenide wafer, or an indium phosphide wafer that needs to be plasma etched.

[0076] S12, placing the substrate to be processed in a plasma vacuum reaction chamber of a plasma etching device provided in any one of the above-mentioned embodiments 1 to 4, and fixing it above the lower electrode 20, so as to etch the substrate to be processed by the etching device. During the etching process, the coil 30 is connected to a first RF power source, one of the upper electrode and the lower electrode is grounded, and the other is connected to a second RF power source.

[0077] Since the plasma etching apparatus provided in any one of the foregoing Embodiments 1 to 4 is used in this embodiment for etching, a strong magnetic field and an electric field can be formed in the reaction chamber, the etching efficiency is improved, and the problem of uneven etching at the edge of the substrate is alleviated.

[0078] Embodiment 6

[0079] This embodiment provides a preparation method of a plasma etching apparatus, and the method specifically includes the following steps:

[0080] S21, providing a plasma vacuum reaction chamber.

[0081] S22, providing an upper electrode 10 and a lower electrode 20, wherein the upper electrode 10 includes a gas spraying area S1 for spraying gas downward and an edge area S2 surrounding the gas spraying area S1.

[0082] S23, opening a plurality of windows 11 uniformly distributed in the circumferential direction in the edge area S2, each window 11 being circular or substantially square, and of course, it can also be configured into any other suitable shape, and this embodiment does not make any specific limitation thereto.

[0083] S24, arranging an insulating member 12 in each window 11 to seal each window 11. Among them, the insulating member 12 can be made of any suitable insulating material such as ceramics or glass, and the present invention does not make any specific limitation thereto.

[0084] S25, relatively arranging the upper electrode 10 and the lower electrode 20 in the plasma vacuum reaction chamber.

[0085] S26, arranging coils 30 (see Figure 3 ) corresponding to each of the insulating members 12, or arranging a coil 30 (see Figure 4 ) on the edge area, which extends along the circumferential direction of the edge area and passes above all the insulating members 12.

[0086] During etching, the coil 30 is connected to a first radio frequency power source, the upper electrode 10 is grounded, and the lower electrode 20 can be connected to a plurality of radio frequency power sources, including a second radio frequency power source and a bias power source. Among them, the radio frequency signal generated by the first radio frequency power source generates a magnetic field through the coil 30; the radio frequency signal generated by the second radio frequency power source plasmaizes the gas in the reaction chamber through the capacitance formed by the upper electrode 10 and the lower electrode 20; the bias power source forms a bias voltage on the substrate to be processed on the upper surface of the lower electrode 20 to achieve etching of the substrate to be processed.

[0087] In a preferred embodiment, the frequencies of the first radio frequency power source, the second radio frequency power source, and the bias power source are all 400 KHz - 100 MHz.

[0088] This embodiment combines the advantages of ICP and CCP. By providing the upper electrode 10 which can be grounded, it can solve the problem that the ICP etching device has poor grounding and cannot withstand a high-power bias electric field. At the same time, by circumferentially and uniformly opening a plurality of windows 11 in the edge region S2 of the upper electrode 10 and respectively providing insulating members 12 at each window 11 to form a dielectric window, the magnetic field generated by the radio frequency power supply loaded on the coil 30 above the dielectric window can pass through the dielectric window, while the electric field below the dielectric window cannot penetrate upward, thus solving the problem of uneven etching caused by low plasma density at the substrate edge. It can be seen that this embodiment can form a strong magnetic field and electric field in the reaction chamber, improve the etching efficiency, alleviate the problem of uneven edge etching, and has a simple structure and low cost, which is beneficial to large-scale application in the semiconductor industry.

[0089] Although the specific embodiments of the present invention have been described above, those skilled in the art should understand that this is only an example, and the protection scope of the present invention is defined by the appended claims. Without departing from the principles and essence of the present invention, those skilled in the art can make various changes or modifications to these embodiments, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A plasma etching device combining ICP and CCP, characterized in that: It includes an upper electrode and a lower electrode which are relatively arranged at the top and the bottom of the plasma vacuum reaction chamber; The upper electrode comprises a gas spraying area for spraying gas downward and an edge area surrounding the gas spraying area, the edge area is provided with a plurality of windows evenly distributed along the circumference, and each of the windows is closed by an insulating member; Wherein, coils are arranged on each of the insulating members in a one-to-one correspondence, or coils are arranged on the edge region and extend along the circumference of the edge region and pass over all the insulating members.

2. The plasma etching device according to claim 1, characterized in that: The insulating member includes a filling portion, which includes a first transverse plate and a boss extending longitudinally from the first transverse plate. The first transverse plate is abutted and fixed to the surface of the upper electrode, and the boss is filled in the corresponding window to seal the corresponding window.

3. The plasma etching device according to claim 2, characterized in that: The insulating member also includes a card slot, which includes a second transverse plate and a card slot extending longitudinally from the second transverse plate. The second transverse plate and the first transverse plate are abutted and fixed on the opposite surface of the upper electrode. The card slot is installed in the corresponding window so that the boss can be clamped in the card slot.

4. The plasma etching device according to claim 1, characterized in that: The device also includes an electrostatic chuck disposed above the lower electrode for fixing the substrate to be processed; The bottom surface of the electrostatic chuck is also provided with a heat regulating element, and the heat regulating element is divided into a plurality of temperature regulating areas distributed radially; Each of the temperature adjustment areas is provided with a temperature sensor and a circumferentially extending flow channel, and each of the flow channels is connected to a cooling fluid source through a first valve and is connected to a heating fluid source through a second valve; Each of the first valve, the second valve and the temperature sensor is connected to a controller, and the controller is used to adjust the opening of the corresponding first valve and the second valve according to the difference between the measurement value of each temperature sensor and the target temperature of the corresponding temperature adjustment area.

5. The plasma etching device according to claim 1, characterized in that: The coil is connected to a first radio frequency power source, the upper electrode is grounded, and the lower electrode is connected to a second radio frequency power source and a bias power source.

6. The plasma etching device according to claim 5, characterized in that: The frequencies of the first RF power source, the second RF power source and the bias power source are 400KHz-100MHz.

7. The plasma etching device according to claim 1, characterized in that: The area of ​​the gas spraying zone is greater than 80% of the substrate to be processed.

8. The plasma etching device according to claim 1, characterized in that: The insulating member is made of ceramic or glass material.

9. The plasma etching device according to claim 1, characterized in that: The window is circular or approximately square.

10. A plasma etching method, characterized in that: include: obtaining a substrate to be processed; The substrate to be processed is fixed above the lower electrode in the plasma etching device as described in any one of claims 1 to 9, so as to etch the substrate to be processed by the plasma etching device. During the etching process, the coil is connected to a first RF power source, one of the upper electrode and the lower electrode is grounded, and the other is connected to a second RF power source.

11. A method for preparing a plasma etching device, characterized in that: include: Providing a plasma vacuum reaction chamber; Providing an upper electrode and a lower electrode, wherein the upper electrode comprises a gas spraying area for spraying gas downward and an edge area surrounding the gas spraying area; A plurality of windows evenly distributed along the circumference are provided in the edge area; An insulating member is arranged in each of the windows to seal each of the windows; The upper electrode and the lower electrode are arranged oppositely at the top and the bottom of the plasma vacuum reaction chamber; Coils are arranged on the insulating members in a one-to-one correspondence, or coils are arranged on the edge region to extend along the circumference of the edge region and pass over all the insulating members.

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