Semiconductor processing apparatus and etching method

Abstract

The application provides a semiconductor process equipment and an etching method. The equipment comprises a plasma excitation device and a process chamber. The plasma excitation device comprises a first sub-cavity, a second sub-cavity and a first radio frequency component and a second radio frequency component connected with the first sub-cavity and the second sub-cavity respectively. The first sub-cavity is communicated with a first gas source capable of delivering a first process gas to the first sub-cavity. The first radio frequency component is used to excite the first gas source into a first plasma. The second sub-cavity is communicated with a second gas source capable of delivering a second process gas to the second sub-cavity. The second radio frequency component is used to excite the gas and / or the first plasma in the second sub-cavity, so that the reaction product containing free radicals is generated in the second sub-cavity. The free radicals can chemically react with the material on the wafer surface to realize the chemical dry etching of the wafer by the free radicals, thereby reducing the damage to the wafer surface.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, specifically relating to a semiconductor process equipment and an etching method. Background Technology

[0002] Etching equipment is used in integrated circuits to remove exposed materials on the wafer surface in a controlled manner, thereby creating patterned material layers, such as pattern transfer, mask stripping, feature layer thinning, or surface treatment. The use of denser three-dimensional structures and a wider variety of materials in memory and logic chips places higher demands on semiconductor etching equipment and processes, such as higher selectivity, lower damage, maintaining the integrity of high aspect ratio structures, and controlling the morphology of fine feature layers.

[0003] Current wafer etching technologies include wet etching based on chemical etching solutions and dry etching based on plasma. Wet etching is costly due to the expensive etching solutions and the management of process waste, and because chemical etching solutions have a certain surface tension, they can easily cause high aspect ratio structures to collapse or deform. Dry etching based on plasma can damage the structures that need to be preserved on the wafer due to the plasma bombardment effect. Summary of the Invention

[0004] This invention at least partially solves the problems of existing wet etching solutions causing damage to wafer surface structures and dry etching causing high damage, and provides a semiconductor process equipment and an etching method.

[0005] This invention provides a semiconductor process apparatus, which includes a plasma excitation device and a process chamber: wherein the plasma excitation device includes a first radio frequency component, a second radio frequency component, and a first sub-cavity and a second sub-cavity that are interconnected.

[0006] The first sub-cavity is connected to a first gas source, which can deliver a first process gas to the first sub-cavity; the first radio frequency component is connected to the first sub-cavity and is used to feed radio frequency power into the first sub-cavity when it is turned on, so as to excite the first process gas to form a first plasma.

[0007] The second sub-cavity is connected to a second gas source, which can supply a second process gas to the second sub-cavity so that the first plasma and the second process gas mix and react to generate reaction products containing free radicals; wherein, the free radicals can react with the wafer surface material;

[0008] The second sub-cavity is connected to the process chamber to allow the free radicals to be introduced into the process chamber;

[0009] The second radio frequency component is connected to the second sub-cavity and is used to feed radio frequency power into the second sub-cavity when turned on, so as to excite the gas and / or the first plasma inside the second sub-cavity.

[0010] Optionally, semiconductor process equipment may also include filter nozzles;

[0011] The filter nozzle is connected at both ends to the second sub-cavity and the process chamber, respectively, and is used to filter the gas delivered from the second sub-cavity to the process chamber to prevent charged particles from entering the process chamber.

[0012] Optionally, the first process gas is the main process gas; the second process gas is the auxiliary process gas.

[0013] Optionally, the air inlet of the first sub-cavity is located in the central region of the top of the first sub-cavity for communication with the first air source;

[0014] A central air inlet is provided in the central region of the top of the second sub-cavity; the first sub-cavity is stacked in the central region of the top of the second sub-cavity and communicates with the central air inlet of the second sub-cavity; the diameter of the first sub-cavity is smaller than the diameter of the second sub-cavity;

[0015] An edge air inlet is also provided in the edge region at the top of the second sub-cavity for communication with the second air source.

[0016] Optionally, the filter nozzle includes at least one layer of grid plate; the grid plate has a plurality of filter holes distributed therein, all of which are used to allow gas to pass through and block charged particles from passing through.

[0017] Optionally, the diameter of the filter pores ranges from 1 to 3.8 mm; the number of filter pores ranges from 100 to 3000.

[0018] Optionally, the semiconductor process equipment also includes a base, radio frequency electrodes, and a third radio frequency component; wherein the base is disposed inside the process chamber and is used to support the wafer;

[0019] The radio frequency electrode is disposed at the bottom of the base; the third radio frequency component is electrically connected to the radio frequency electrode and is used to feed bias radio frequency power to the radio frequency electrode when it is turned on.

[0020] As another technical solution, embodiments of the present invention also provide an etching method, which is applied to the semiconductor process equipment described above, and includes the following steps:

[0021] S1. Introduce a first process gas and a second process gas into the first sub-cavity and the second sub-cavity respectively, and turn on at least one of the first radio frequency component and the second radio frequency component to form a reaction product containing free radicals in the second sub-cavity.

[0022] S2. Etching process is carried out in the process chamber.

[0023] Optionally, step S1 includes;

[0024] S11. Introduce the first process gas into the first sub-cavity;

[0025] S12. Turn on the first radio frequency component to excite the first process gas into the first plasma;

[0026] S13. Introduce a second process gas into the second sub-cavity to mix the second process gas with the first plasma and react to generate free radicals;

[0027] S14. The gas in the second sub-cavity is introduced into the process chamber so that the free radicals react with the wafer surface material to form an etching reaction.

[0028] Optionally, step S3 further includes:

[0029] The second radio frequency component is activated to excite the gas and / or the first plasma inside the second sub-cavity.

[0030] The present invention has the following beneficial effects:

[0031] The semiconductor process apparatus provided in this invention includes a process chamber and a plasma excitation device connected thereto. The plasma excitation device includes a first sub-cavity and a second sub-cavity connected to each other, as well as a first radio frequency (RF) component and a second RF component respectively connected to the first and second sub-cavities. Both the first and second RF components are capable of exciting the gas in their respective sub-cavities when activated. This allows the first process gas to be first excited into a first plasma in the first sub-cavity, which then enters the second sub-cavity and mixes with the second process gas to react and generate free radicals. Alternatively, the first plasma can be secondary excited in the second sub-cavity to increase the amount of free radicals generated.

[0032] Because free radicals are highly reactive and uncharged particles, the chemical reaction between free radicals and wafers is extremely efficient. Furthermore, since free radicals are only subject to their own gravity, they do not bombard the wafer surface, thus reducing damage. Moreover, the first and second sub-cavities provided in this embodiment have independent gas inlets, allowing for independent control of the intake amounts of the first and second process gases. This enables precise control of the ratio of the two process gases, and consequently, precise control of the process results. Attached Figure Description

[0033] Figure 1 A simplified structural diagram of a semiconductor process equipment provided in an embodiment of the present invention;

[0034] Figure 2 This is a top view schematic diagram of the filter nozzle provided in an embodiment of the present invention. Detailed Implementation

[0035] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] It is understood that the specific embodiments and accompanying drawings described herein are merely for explaining the invention and are not intended to limit the invention.

[0037] It is understood that, without conflict, the various embodiments of the present invention and the features thereof can be combined with each other.

[0038] It is understood that, for ease of description, the accompanying drawings of this invention only show the parts related to the embodiments of this invention, while the parts unrelated to the embodiments of this invention are not shown in the drawings.

[0039] It is understood that, without conflict, the functions and steps marked in the flowcharts and block diagrams of the embodiments of the present invention may occur in a different order than that marked in the accompanying drawings.

[0040] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

[0041] This embodiment provides a semiconductor process apparatus, which includes a plasma excitation device and a process chamber. Wherein, as... Figure 1 As shown, the plasma excitation device 1 includes a first sub-cavity 11 and a second sub-cavity 12 that are interconnected, as well as a first radio frequency component 13 and a second radio frequency component 14.

[0042] The first sub-cavity 11 is connected to the first gas source 3, which can supply a first process gas to the first sub-cavity 11. A first radio frequency (RF) component 13 is connected to the first sub-cavity 11 and is used to feed RF power into the first sub-cavity 11 when turned on, to excite the first process gas into a first plasma. It is readily understood that the first RF component 13 does not feed RF power into the first sub-cavity 11 when turned off.

[0043] The second sub-cavity 12 is connected to the second gas source 4, which supplies a second process gas to the second sub-cavity 12. This allows the first plasma to mix with the second process gas and react to generate free radicals. These free radicals can react with wafer surface materials, such as during etching. It should be noted that free radicals are highly reactive and uncharged particles, therefore they are not subject to the electric field force of an external electric field; that is, they are only subject to gravity.

[0044] The second radio frequency (RF) component 14 is connected to the second sub-cavity 12 and is used to feed RF power into the second sub-cavity 12 when it is turned on, so as to excite the gas inside the second sub-cavity 12. This allows RF power to be fed into the second sub-cavity 12 after the first plasma enters and mixes with the second process gas, thereby exciting the gas and / or the first plasma in the second sub-cavity 12. Specifically, the RF power fed into the second RF component 14 can excite at least one of the second process gas, the first process gas not excited in the first sub-cavity 11, and the first plasma in the second sub-cavity 12. By causing secondary excitation of the first plasma, secondary dissociation of the first plasma can be achieved, thereby increasing the generated plasma density and, consequently, the density of free radicals generated in the reaction, thus improving process efficiency. It is readily understood that the second RF component 14 does not feed RF power into the second sub-cavity 12 when it is turned off. Thus, by first turning on the first RF component 13 and then turning on the second RF component 14, or by not turning on the second RF component 14, reaction products containing free radicals can be formed in the second sub-cavity 12.

[0045] The second sub-cavity 12 is connected to the air inlet at the top of the process chamber 2 to introduce free radicals into the process chamber 2, thereby enabling the free radicals to react with the wafer surface material. As mentioned above, since the free radicals are only subject to their own gravity, they do not possess high kinetic energy and therefore do not bombard the wafer surface. Therefore, compared to existing dry etching equipment that uses electric field-driven plasma to bombard the wafer surface, the semiconductor process equipment proposed in this embodiment can significantly reduce damage to the wafer surface, thus ensuring that structures that need to be preserved, such as oxide sidewalls or masks, nitride sidewalls or masks, are not damaged. Moreover, compared to existing wet etching equipment that uses etching solutions to etch the wafer surface, the semiconductor process equipment proposed in this embodiment can utilize gaseous free radicals to chemically react with the wafer surface for etching. Therefore, this embodiment can avoid the collapse or deformation of high aspect ratio structures on the wafer surface due to the surface tension of the etching solution.

[0046] As described above, the semiconductor process equipment proposed in this embodiment mainly utilizes free radicals for semiconductor processing. This process primarily involves chemical reactions, with only a small amount or even none of physical etching using plasma bombardment. Taking the etching process as an example, the etching process occurring in process chamber 2 can be considered a dry chemical etching process. Therefore, the etching efficiency and etching amount can be controlled by controlling the types and ratios of the components involved in the chemical reaction. That is, the etching process results can be controlled by selecting the types of the first process gas and the second process gas, and by adjusting the ratio of the first process gas and the second process gas. Moreover, since the first sub-cavity 11 and the second sub-cavity 12 provided in this embodiment are respectively connected to the first gas source 3 and the second gas source 4, that is, the first sub-cavity 11 and the second sub-cavity 12 are independently inlet gas, the inlet amounts of the first process gas and the second process gas can be independently controlled to achieve precise control of the ratio of the two process gases, thereby achieving precise control of the etching process results.

[0047] Taking the etching process of silicon oxide wafers (SiO2) in the semiconductor process equipment provided in this embodiment, using nitrogen fluoride (NF3) as the first process gas and ammonia (NH3) as the second process gas as an example, the process flow includes: firstly, introducing NF3 gas into the first sub-cavity 11 and exciting the NF3 gas to form a first plasma, which contains F free radicals (F*); after the first plasma enters the second sub-cavity 12, introducing H2 gas into the second sub-cavity 12, so that F* and H2 react to generate HF and Finally HF and They react with SiO2 to produce volatile reaction byproducts, namely SiF. X and H X SiF XThis completes the etching of the wafer.

[0048] In some embodiments, such as Figure 1 As shown, the air inlet of the first sub-cavity 11 is located in the central region of its top, for communication with the first gas source 3 to achieve central air intake. A central air inlet is provided in the central region of the top of the second sub-cavity 12, and an edge air inlet is also provided in the edge region of its top. The first sub-cavity 11 is stacked in the central region of the top of the second sub-cavity 12, with the diameter of the first sub-cavity 11 being smaller than the diameter of the second sub-cavity 12 to avoid obstructing the edge air inlets. The central air inlet of the top of the second sub-cavity 12 is used to communicate with the first sub-cavity 11; the edge air inlet of the top of the second sub-cavity 12 is used to communicate with the second gas source 4. In this way, gas containing the first plasma can be introduced from the central region of the second sub-cavity 12, and a second process gas can be introduced from the edge region, so that the first plasma and the second process gas can be mixed by the flow of the gas and the diffusion of the gas, and react to generate free radicals.

[0049] Furthermore, in some embodiments, the first radio frequency component 13 includes a first radio frequency source 131, a first radio frequency coil 132, and a first matching unit 133; the first radio frequency coil 132 is wound around the outer periphery of the first sub-cavity 11; the first radio frequency source 131 and the first radio frequency coil 132 are connected through the first matching unit 133, which is used to match the radio frequency power output by the first radio frequency source 131 to the first radio frequency coil 132, so as to form a radio frequency electric field in the first sub-cavity 11, so that it can be excited into a first plasma after the first process gas enters the first sub-cavity 11. In this way, an inductively coupled plasma source (i.e., inductively coupled plasma, hereinafter referred to as ICP) can be formed on the outer periphery of the first sub-cavity 11. The ICP source has the advantage of being able to generate plasma with a high concentration.

[0050] Furthermore, in some embodiments, the second radio frequency component 14 includes a second radio frequency source 141, a second radio frequency coil 142, and a second matching unit 143; the second radio frequency coil 142 is wound around the outer periphery of the second sub-cavity 12; the second radio frequency source 141 and the second radio frequency coil 142 are connected through the second matching unit 143, which is used to match the radio frequency power output by the second radio frequency source 141 to the second radio frequency coil 142. In this way, an ICP source can be formed on the outer periphery of the second sub-cavity 12; and the ICP source is used to form a radio frequency electric field in the second sub-cavity 12 so that it can reignite after the first plasma enters the interior of the second sub-cavity 12 and mixes with the second process gas.

[0051] Furthermore, the plasma density in the edge region and the plasma density in the center region of the second sub-cavity 12 can be adjusted by changing the power ratio of the first RF source 131 and the second RF source 141, thereby adjusting the edge reaction rate and the center reaction rate. Taking the etching process as an example, if the etching result of the wafer shows that the edge etching rate is greater than the center etching rate, the power ratio of the first RF source 131 and the second RF source 141 can be appropriately reduced to improve the uniformity of the plasma density distribution, thereby reducing the difference in etching rate between the wafer center and the edge, and thus improving the uniformity of the etching process.

[0052] For example, the ratio of the first radio frequency source 131 to the second radio frequency source 141 is, for example, 3:1 to 1:3.

[0053] For example, the frequency of the first radio frequency source 131 and the second radio frequency source 141 can both be 13.56MHz, and the power range can both be 2000~5000W.

[0054] It should be noted that in some etching processes, the second radio frequency source 141 can also be kept off, so that only the electrons and ions in the first plasma collide with the gas molecules contained in the second process gas, which can promote the dissociation of the second process gas molecules, thereby promoting the reaction between the first plasma and the second process gas.

[0055] For example, such as Figure 1 As shown, the first radio frequency component 13 and the second radio frequency component 14 also include a Faraday shielding device 15. Specifically, the two Faraday shielding devices 15 are respectively disposed between the outer wall of the first sub-cavity 11 and the first radio frequency coil 132 and between the outer wall of the second sub-cavity 12 and the second radio frequency coil 142. Both Faraday shielding devices 15 are used to reduce the sputtering damage of charged particles to the sidewall of the cavity and improve the service life of the equipment.

[0056] In some embodiments, under the conditions for etching reaction inside the aforementioned process chamber 2, the first process gas is the main etching gas participating in the etching reaction, i.e., a gas containing components that perform the main etching function; the second etching gas is the auxiliary etching gas participating in the etching reaction, i.e., a gas containing components that perform protective and catalytic functions; correspondingly, the aforementioned free radicals can undergo the etching reaction with the wafer surface material. Thus, the main etching gas can be first excited into a first plasma in the first sub-cavity 11, and can be re-excited after entering the second sub-cavity 12, thereby increasing the density of the components performing the main etching function and improving the utilization rate of the main etching gas.

[0057] In some embodiments, the semiconductor process equipment further includes a filter nozzle 5. The filter nozzle 5 is located between the second sub-cavity 12 and the process chamber 2, and its inlet and outlet ends are respectively connected to the second sub-cavity 12 and the process chamber 2. It is used to filter the gas supplied from the second sub-cavity 12 to the process chamber 2, preventing charged particles in the gas from entering the process chamber 2. Specifically, the charged particles include positive ions, negative ions, and electrons. Since the gas supplied from the second sub-cavity 12 to the process chamber 2 contains charged particles, free radicals, and neutral particles, filtering out charged particles can significantly reduce the possibility of physical bombardment participating in the etching process, thereby minimizing wafer surface damage. Furthermore, filtering out charged particles can increase the concentration of free radicals in the process chamber 2, thereby increasing the efficiency of the chemical reaction between free radicals and the wafer material, and thus improving the efficiency of the etching process.

[0058] Furthermore, in some embodiments, the filter nozzle 5 includes at least one layer of slats; such as Figure 2 As shown, the grid plate has multiple filter holes 51 distributed throughout, each designed to allow gas to pass through while blocking charged particles. Specifically, charged particles collide with the inner surface of the filter holes 51, dissolving their charge on the inner surface of the filter holes 51. Neutral particles and free radicals, however, can pass through the filter holes 51 and reach the wafer surface. Therefore, the filtration rate of the filter nozzle 5 for charged particles can be adjusted by modifying the area and shape of the inner surface of the filter holes 51.

[0059] For example, the filtration efficiency of the filter nozzle 5 for charged particles is greater than 95%.

[0060] For example, the shape of the filter aperture 51 may be cylindrical, conical, or a combination of both.

[0061] For example, the diameter of the filter through-hole 51 ranges from 1 to 3.8 mm; the number of filter through-holes 51 ranges from 100 to 3000.

[0062] In some embodiments, the semiconductor process equipment further includes a base 21, a radio frequency (RF) electrode 22, and a third RF component 23; wherein the base 21 is disposed inside the process chamber 2 and is used to support the wafer. The RF electrode 22 is disposed inside the base 21; the third RF component 23 is electrically connected to the RF electrode 22 and is used to feed bias RF power to the RF electrode 22 when turned on, so as to dissociate the gas entering the process chamber 2 again with a small power, exciting a small number of low-energy charged particles. Therefore, a small number of low-energy charged particles can be used to bombard the wafer surface; and because the charged particles have low energy, even if the charged particles are driven to physically bombard the wafer, damage to the wafer surface can be reduced. It is readily understood that the third RF component 23 does not feed bias RF power to the RF electrode 22 when turned off.

[0063] Since free radicals are driven solely by gravity, they struggle to penetrate high aspect ratio structures in some etching processes. In such cases, the third radio frequency (RF) component 23 can be activated to attract a small number of low-energy charged particles to bombard the wafer surface. This utilizes the highly directional nature of physical bombardment to achieve anisotropic etching of the wafer. However, in etching processes requiring low aspect ratio and low damage, the third RF component 23 can remain off, allowing isotropic chemical etching of the wafer to be performed solely using free radicals. Therefore, the RF electrode 22 and the third RF component 23 proposed in this embodiment enable the semiconductor process chamber to perform both isotropic and anisotropic etching, thereby expanding the application range of the semiconductor process chamber.

[0064] For example, the third radio frequency component 23 includes a third radio frequency source 231 and a third matching unit 232; the third matching unit 232 is connected to the third radio frequency source 231 and the radio frequency electrode 22 respectively, and is used to match the bias radio frequency power output by the third radio frequency source 231 into the radio frequency electrode 22.

[0065] For example, the frequency of the third radio frequency source 231 can be 13.56MHz, and the power range can be 200 to 2000W.

[0066] Based on the semiconductor process equipment described above, this embodiment also provides an etching method, which includes the following steps:

[0067] S1. Introduce a first process gas and a second process gas into the first sub-cavity 11 and the second sub-cavity 12 respectively, and turn on at least one of the first radio frequency component 13 and the second radio frequency component 14 to form a reaction product containing free radicals in the second sub-cavity 12.

[0068] S2. An etching process is performed in the process chamber to chemically etch the wafer surface using free radicals.

[0069] The etching method proposed in this embodiment utilizes the high reactivity of free radicals, which can reduce the damage to the wafer caused by plasma bombardment and avoid the collapse or deformation of the wafer surface structure caused by the surface tension of the etching solution.

[0070] Furthermore, step S1 specifically includes the following steps:

[0071] S11. Introduce the first process gas into the first sub-cavity 11;

[0072] S12. Turn on the first radio frequency component 13 and feed radio frequency power into the first sub-cavity 11 to excite the first process gas into the first plasma;

[0073] S13. Introduce a second process gas into the second sub-cavity 12 to mix the second process gas with the first plasma and react to generate free radicals;

[0074] S14. The gas in the second sub-cavity 12 is introduced into the process chamber 2 so that the free radicals react with the wafer surface material to form an etching reaction.

[0075] In some embodiments, step S13 above further includes:

[0076] The second radio frequency component 14 is turned on, and radio frequency power is fed into the second sub-cavity 12 to excite the gas and / or the first plasma inside the second sub-cavity. This excites the second process gas into plasma, excites the first process gas that was not excited in the first sub-cavity 11 into the first plasma, and excites the first plasma a second time, thereby increasing the amount of free radicals generated by the reaction occurring in the second sub-cavity 12, and thus improving the etching efficiency.

[0077] Alternatively, in some other embodiments, step S1 specifically includes the following steps:

[0078] S11. Introduce the first process gas into the first sub-cavity 11 and keep the first radio frequency component 13 off;

[0079] S12, allowing the first process gas to enter the second sub-cavity 12;

[0080] S13. Introduce a second process gas into the second sub-cavity 12 to mix the second process gas with the first process gas.

[0081] S14. Turn on the second radio frequency component 14 to excite the mixture of the first process gas and the second process gas in the second sub-cavity 12 to generate reaction products.

[0082] It should be noted that, since the above implementation method involves exciting the first and second process gases in a non-plasmic state, the excitation efficiency and reaction efficiency are both low, resulting in the reaction products containing only a small amount of free radicals.

[0083] In some embodiments, when a third RF component 23 for feeding bias RF power to the RF electrode 22 is provided in the process chamber 2, the above step S4 further includes:

[0084] The third radio frequency component 23 is turned on to excite the gas entering the process chamber 2 again and generate a small number of low-energy charged particles. The charged particles bombard the wafer surface, thereby using a small number of charged particles to physically etch the wafer to improve the aspect ratio of the etching process.

[0085] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A semiconductor process apparatus, characterized in that, It includes a plasma excitation device and a process chamber: the process chamber is used for etching reactions; the plasma excitation device includes a first radio frequency component, a second radio frequency component, and a first sub-cavity and a second sub-cavity that are interconnected. The first sub-cavity is connected to a first gas source, which can deliver a first process gas to the first sub-cavity; the first radio frequency component is connected to the first sub-cavity and is used to feed radio frequency power into the first sub-cavity when it is turned on, so as to excite the first process gas to form a first plasma. The second sub-cavity is connected to a second gas source, which can supply a second process gas to the second sub-cavity so that the first plasma and the second process gas mix and react to generate reaction products containing free radicals; wherein, the first process gas is the main etching gas participating in the etching reaction; the second process gas is the auxiliary etching gas participating in the etching reaction; the free radicals can react with the wafer surface material to undergo the etching reaction; The second sub-cavity is connected to the process chamber to allow the free radicals to be introduced into the process chamber; The second radio frequency component is connected to the second sub-cavity and is used to feed radio frequency power into the second sub-cavity when turned on, so as to excite the gas and / or the first plasma inside the second sub-cavity.

2. The semiconductor process equipment according to claim 1, characterized in that, It also includes filter nozzles; The filter nozzle is located between the second sub-cavity and the process chamber, and is used to block charged particles in the gas delivered from the second sub-cavity to the process chamber from entering the process chamber.

3. The semiconductor process equipment according to claim 1, characterized in that, The air inlet of the first sub-cavity is located in the central region of the top of the first sub-cavity and is used to communicate with the first air source; A central air inlet is provided in the central region of the top of the second sub-cavity; the first sub-cavity is stacked in the central region of the top of the second sub-cavity and communicates with the central air inlet of the second sub-cavity; the diameter of the first sub-cavity is smaller than the diameter of the second sub-cavity; An edge air inlet is also provided in the edge region at the top of the second sub-cavity for communication with the second air source.

4. The semiconductor process equipment according to claim 2, characterized in that, The filter nozzle includes at least one layer of grid plate; the grid plate has multiple filter holes distributed therein, each of which is used to allow gas to pass through and block charged particles from passing through.

5. The semiconductor process equipment according to claim 4, characterized in that, The diameter of the filter pores ranges from 1 to 3.8 mm; the number of filter pores ranges from 100 to 3000.

6. The semiconductor process equipment according to any one of claims 1-5, characterized in that, The semiconductor process equipment further includes a base, radio frequency electrodes, and a third radio frequency component; wherein the base is disposed inside the process chamber and is used to support the wafer; The radio frequency electrode is disposed inside the base; the third radio frequency component is electrically connected to the radio frequency electrode and is used to feed bias radio frequency power to the radio frequency electrode when it is turned on.

7. An etching method, applied to the semiconductor process equipment as described in any one of claims 1-6, comprising: S1. A first process gas and a second process gas are respectively introduced into the first sub-cavity and the second sub-cavity, and at least one of the first radio frequency component and the second radio frequency component is turned on to form a reaction product containing free radicals in the second sub-cavity; wherein, the first process gas is the main etching gas participating in the etching reaction; the second process gas is the auxiliary etching gas participating in the etching reaction; the free radicals are capable of reacting with the wafer surface material in the etching reaction; S2. The etching process is carried out in the process chamber.

8. The etching method according to claim 7, characterized in that, Step S1 includes: S11. Introduce the first process gas into the first sub-cavity; S12. Turn on the first radio frequency component to excite the first process gas into the first plasma; S13. Introduce a second process gas into the second sub-cavity to mix the second process gas with the first plasma and react to generate the reaction product. S14. The reaction products in the second sub-cavity are introduced into the process chamber so that the free radicals react with the wafer surface material to form an etching reaction.

9. The etching method according to claim 8, characterized in that, Step S13 also includes: The second radio frequency component is activated to excite the gas and / or the first plasma inside the second sub-cavity.

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