Semiconductor structure and method of forming the same

Abstract

The present application relates to the technical field of integrated circuit, and especially relates to a semiconductor structure and a forming method thereof. The forming method of the semiconductor structure comprises the following steps: forming a capacitor substrate, wherein the capacitor substrate comprises a plurality of capacitor switching structures and an isolation layer located between adjacent capacitor switching structures and covering top surfaces of the capacitor switching structures; removing the isolation layer covering the top surfaces of the capacitor switching structures to expose the capacitor switching structures; oxidizing surfaces of the capacitor substrate exposed with the capacitor switching structures to form an oxide layer; and removing the oxide layer to expose the capacitor switching structures. The present application reduces defects on surfaces of the capacitor switching structures and avoids short circuit between adjacent capacitor switching structures, thereby improving the electrical performance of the semiconductor structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of integrated circuits, and in particular to a semiconductor structure and a forming method thereof. BACKGROUND

[0002] Dynamic Random Access Memory (DRAM) is a commonly used semiconductor structure in electronic devices such as computers, which is composed of a plurality of memory cells, each of which usually includes a capacitor for storing electric charge and a transistor for accessing the capacitor. The gate of the transistor is electrically connected to a word line, the source is electrically connected to a bit line, and the drain is electrically connected to the capacitor. The word line voltage on the word line can control the opening and closing of the transistor, so that data information stored in the capacitor can be read through the bit line, or data information can be written into the capacitor.

[0003] The capacitor is connected to the drain through a capacitor adapter structure in the capacitor substrate. However, due to the limitations of current manufacturing processes, defects are prone to occur on the surface of the capacitor substrate, and short circuits are prone to occur between adjacent capacitor adapter structures.

[0004] Therefore, how to reduce the defects on the surface of the capacitor substrate and avoid short circuits between adjacent capacitor adapter structures to improve the electrical performance of the semiconductor structure is a technical problem to be solved at present. SUMMARY

[0005] The present application provides a semiconductor structure and a forming method thereof, which is used to solve the problem that the surface of the existing capacitor substrate is prone to defects and short circuits are prone to occur between adjacent capacitor adapter structures, so as to improve the electrical performance of the semiconductor structure.

[0006] In order to solve the above problems, the present application provides a forming method of a semiconductor structure, comprising the following steps:

[0007] forming a capacitor substrate, the capacitor substrate comprising a plurality of capacitor adapter structures and an isolation layer located between adjacent capacitor adapter structures and covering the top surface of the capacitor adapter structures;

[0008] removing the isolation layer covering the top surface of the capacitor adapter structures to expose the capacitor adapter structures;

[0009] oxidizing the surface of the capacitor substrate exposed with the capacitor adapter structures to form an oxide layer;

[0010] removing the oxide layer to expose the capacitor adapter structures.

[0011] Optionally, the specific steps of forming a capacitor substrate include:

[0012] providing a substrate, the substrate having a plurality of capacitor contact regions therein;

[0013] forming a plurality of capacitor transfer structures on the substrate surface, and each of the plurality of capacitor transfer structures is electrically connected to one of the plurality of capacitor contact regions;

[0014] forming an isolation layer filling the gaps between adjacent capacitor transfer structures and covering the top surfaces of the capacitor transfer structures.

[0015] Optionally, the specific step of removing the isolation layer covering the top surfaces of the capacitor transfer structures comprises:

[0016] using a dry etching process to etch the isolation layer.

[0017] Optionally, the material of the isolation layer is a nitride material; and the specific step of using a dry etching process to etch the isolation layer further comprises:

[0018] using a mixed gas of CF4, CHF3 and O2 as etching gas to etch the isolation layer.

[0019] Optionally, the specific step of oxidizing the capacitor substrate to expose the surfaces of the capacitor transfer structures comprises:

[0020] using O2 plasma to oxidize the capacitor substrate to expose the surfaces of the capacitor transfer structures.

[0021] Optionally, the reaction temperature when using O2 plasma to oxidize the capacitor substrate to expose the surfaces of the capacitor transfer structures is 25°C to 300°C.

[0022] Optionally, the specific step of using O2 plasma to oxidize the capacitor substrate to expose the surfaces of the capacitor transfer structures comprises:

[0023] transmitting a mixed gas plasma comprising at least O2 plasma and H2N2 plasma to the surfaces of the capacitor substrate exposed to the capacitor transfer structures.

[0024] Optionally, the flow rate of the mixed gas plasma is 100sccm to 15000sccm, and the pressure of the mixed gas plasma is 10mtorr to 10000mtoor.

[0025] Optionally, the specific step of transmitting a mixed gas plasma comprising at least O2 plasma and H2N2 plasma to the surfaces of the capacitor substrate exposed to the capacitor transfer structures comprises:

[0026] using a radio frequency power of 100W to 10000W to ionize a mixed gas comprising O2 and H2N2 to form a mixed gas plasma;

[0027] transferring the mixed gas plasma to the surface of the capacitive substrate exposed to the capacitive adapter structure.

[0028] Optionally, the step of removing the oxide layer comprises:

[0029] cleaning the capacitive substrate.

[0030] Optionally, the step of cleaning the capacitive substrate comprises:

[0031] cleaning the capacitive substrate with a DHF solution.

[0032] Optionally, the volume ratio of HF to H2O in the DHF solution is (10:1) to (1000:1).

[0033] Optionally, the step of removing the oxide layer comprises:

[0034] removing the oxide layer by a wet etching process.

[0035] Optionally, the step of removing the oxide layer by a wet etching process comprises:

[0036] selecting a wet etchant having an etching selectivity ratio to the oxide layer and the capacitive adapter structure greater than or equal to 10:1 to remove the oxide layer.

[0037] Optionally, the material of the capacitive adapter structure is a metal material; and the step of removing the oxide layer by a wet etching process comprises:

[0038] removing the oxide layer by using a basic solution as the wet etchant.

[0039] Optionally, the step of removing the oxide layer by using a basic solution as the wet etchant comprises:

[0040] removing the oxide layer by using a mixed solution of NH4OH and H2O as the wet etchant.

[0041] Optionally, the volume ratio of NH4OH to H2O in the wet etchant is (5:1) to (1000:1).

[0042] Optionally, after the step of removing the oxide layer, the method further comprises the following step:

[0043] drying the capacitive substrate.

[0044] Optionally, the step of drying the capacitive substrate comprises:

[0045] purging the capacitive substrate with a mixed gas of nitrogen and isopropyl alcohol.

[0046] To solve the above problems, the application further provides a semiconductor structure formed by the method.

[0047] The semiconductor structure and the forming method thereof provided by the application can make the surface of the capacitor switching structure and the conductive particles remaining on the surface of the capacitor switching structure be oxidized by oxidation, so that the surface material of the capacitor substrate is uniform. After the oxidation layer is removed, the defects on the surface of the capacitor switching structure and the particles remaining on the surface of the capacitor switching structure and the surface of the isolation layer can be removed. The defects on the surface of the capacitor switching structure are reduced, and the problem of short circuit between adjacent capacitor switching structures is avoided, so that the electrical performance of the semiconductor structure is improved. BRIEF DESCRIPTION OF DRAWINGS

[0048] FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application; Figure 1 FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application;

[0049] FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application; Figures 2A-2D FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application;

[0050] FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application; Figures 3A-3D FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application;

[0051] FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application; Figures 4A-4E FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application. DETAILED DESCRIPTION

[0052] The semiconductor structure and the forming method thereof provided by the application will be described in detail below with reference to the accompanying drawings.

[0053] The embodiment provides a forming method of a semiconductor structure, and the forming method comprises the following steps: Figure 1 FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application; Figures 2A-2D FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application. As shown in FIG. 1, the forming method of the semiconductor structure comprises the following steps: Figure 1 Figures 2A-2D FIG. 1 is a flowchart of a forming method of a semiconductor structure in the embodiment of the application;

[0054] In step S11, a capacitor substrate 21 is formed, and the capacitor substrate 21 comprises a plurality of capacitor switching structures 211 and an isolation layer 212 located between adjacent capacitor switching structures 211 and covering the top surface of the capacitor switching structure 211, as shown in FIG. 1. Figure 2A

[0055] ​​Optionally, the specific steps of forming the capacitor substrate 21 include:

[0056] providing a substrate 20 having a plurality of capacitor contact regions therein;

[0057] forming a plurality of capacitor transfer structures 211 on the surface of the substrate 20, and the plurality of capacitor transfer structures 211 are electrically connected to the plurality of capacitor contact regions one by one;

[0058] forming an isolation layer 212 filling the gaps between adjacent capacitor transfer structures 211 and covering the top surface of the capacitor transfer structures 211.

[0059] Specifically, the substrate 20 can be, but is not limited to, a silicon substrate. In this embodiment, the substrate 20 is taken as a silicon substrate for illustration. In other examples, the substrate 20 can be a gallium nitride, gallium arsenide, gallium carbide, silicon carbide, or SOI semiconductor substrate. The substrate 20 has a plurality of active regions arranged in an array therein, and each active region includes a bit line contact region and a capacitor contact region. Before forming the plurality of capacitor transfer structures 211, a capacitor contact layer can be formed on the surface of the substrate 20, and the capacitor contact layer has a plurality of capacitor contact points electrically connected to the plurality of capacitor contact regions one by one. The material of the capacitor contact points can be polysilicon. Then, the plurality of capacitor transfer structures 211 are formed and electrically connected to the plurality of capacitor contact points one by one. The material of the capacitor transfer structures 211 can be a conductive metal material, such as tungsten. The plurality of capacitor transfer structures 211 are independent of each other, that is, there are gaps between adjacent capacitor transfer structures 211. In order to avoid the influence between adjacent capacitor transfer structures 211, after forming the plurality of capacitor transfer structures 211, an insulating material is deposited in the gaps between adjacent capacitor transfer structures 211 and covers the top surface of the capacitor transfer structures 211 to form an isolation layer 212 as shown in Figure 2A The material of the isolation layer 212 can be an oxide material (such as silicon dioxide) or a nitride material (such as silicon nitride).

[0060] Step S12, removing the isolation layer 212 covering the top surface of the capacitor transfer structures 211 to expose the capacitor transfer structures 211 as shown in Figure 2B

[0061] Optionally, the specific steps of removing the isolation layer 212 covering the top surface of the capacitor transfer structures 211 include:

[0062] The isolation layer 212 is etched by a dry etching process.

[0063] ​Optionally, the material of the isolation layer 212 is a nitride material; and the step of etching the isolation layer 212 by using a dry etching process further includes:

[0064] The mixed gas of CF4, CHF3 and O2 is used as the etching gas to etch the isolation layer 212.

[0065] Specifically, when the material of the isolation layer 212 is a nitride material such as silicon nitride, the mixed gas of CF4, CHF3 and O2 can be used as the etching gas to etch the isolation layer 212 downward along the direction of the arrow (i.e. the direction perpendicular to the surface of the capacitor substrate 21) to remove part of the isolation layer 212 and expose the top surface of the capacitor switch structure 211, as shown in FIG. 2D. Figure 2B During the etching process by using the mixed gas of CF4, CHF3 and O2 as the etching gas, the plasma formed by the mixed gas of CF4, CHF3 and O2 can damage the top surface of the capacitor switch structure 211, causing the material particles in the capacitor switch structure 211 to be bombarded out, and part of the material particles can be oxidized by O2 to form particulate matter 22 including the material particles and the material particle oxides, which adheres to the surface of the capacitor substrate 21, as shown in FIG. 2E. Figure 2B Figure 2B

[0066] Taking the material of the capacitor switch structure 211 as tungsten as an example, the plasma formed by the mixed gas of CF4, CHF3 and O2 can bombard the surface of the capacitor switch structure 211, causing tungsten particles and tungsten oxide particles to remain on the surface of the capacitor substrate 21.

[0067] In step S13, the surface of the capacitor substrate 21 exposed to the capacitor switch structure 211 is oxidized to form an oxide layer 23, as shown in FIG. 2F. Figure 2C

[0068] After the top surface of the capacitor switch structure 211 is exposed, the material particles remaining on the surface of the capacitor substrate 21 and the top surface of the capacitor switch structure 211 are both oxidized to form the oxide layer 23 with the same composition as the material particle oxides in the present embodiment. The unification of the materials on the top surface of the capacitor substrate 21 facilitates the subsequent complete removal of the particulate matter 22 on the surface of the capacitor substrate 21, avoiding the problem of short circuit between adjacent capacitor switch structures 211; and part or all of the damaged areas on the surface of the capacitor switch structure 211 are removed, reducing or completely eliminating the defects on the surface of the capacitor switch structure 211.

[0069] Optionally, the step of oxidizing the surface of the capacitor substrate 21 exposed to the capacitor switch structure 211 includes:​​​

[0070] The capacitor substrate 21 exposed with the capacitor adapter structure 211 is oxidized by O2 plasma.

[0071] Optionally, the reaction temperature when the capacitor substrate 21 exposed with the capacitor adapter structure 211 is oxidized by O2 plasma is 25°C-300°C. For example, the reaction temperature when the capacitor substrate 21 exposed with the capacitor adapter structure 211 is oxidized by O2 plasma is 25°C-100°C, 150°C-200°C, or 200°C-250°C, and the preferable reaction temperature is 200°C-250°C.

[0072] Optionally, the specific steps of oxidizing the capacitor substrate 21 exposed with the capacitor adapter structure 211 by O2 plasma include:

[0073] The mixed gas plasma including at least O2 plasma and H2N2 plasma is transmitted to the surface of the capacitor substrate 21 exposed with the capacitor adapter structure 211.

[0074] Optionally, the flow rate of the mixed gas plasma is 100sccm-15000sccm. For example, the flow rate of the mixed gas plasma is 100sccm-500sccm, 400sccm-1000sccm, 1000sccm-5000sccm, 8000sccm-12000sccm, or 10000sccm-15000sccm, and the preferable flow rate is 8000sccm-12000sccm. In the initial stage of oxidizing the surface of the capacitor substrate 21 exposed with the capacitor adapter structure 211 by O2 plasma, the flow rate of the mixed gas plasma can be in a relatively high state; in the stage of approaching saturation of oxidation, the flow rate of the mixed gas plasma can be adjusted to a relatively low state. This is because, when the flow rate of the mixed gas plasma is in a relatively high state, the oxidation reaction on the surface of the capacitor adapter structure 211 is mainly performed; when the flow rate of the mixed gas plasma is in a relatively low state, the cleaning of the reaction residues is mainly performed.

[0075] Optionally, the pressure of the mixed gas plasma is 10mtorr-10000mtorr. For example, the pressure of the mixed gas plasma is 10mtorr-100mtorr, 50mtorr-500mtorr, 500mtorr-1200mtorr, or 2000mtorr-10000mtorr, and the preferable pressure is 500mtorr-1200mtorr.

[0076] Optionally, the specific steps of transmitting a mixed gas plasma, including at least O2 plasma and H2N2 plasma, to the surface of the capacitor substrate 21 exposed by the capacitor transfer structure 211 include:

[0077] A mixed gas including O2 and H2N2 is ionized using a radio frequency power of 100W to 10000W to form a mixed gas plasma; for example, the radio frequency power can be 100W to 500W, 500W to 1000W, 2500W to 5000W, or 5000W to 10000W, with a preferred radio frequency power of 2500W to 5000W.

[0078] The mixed gas plasma is transmitted to the surface of the capacitor substrate 21 exposed by the capacitor transfer structure 211.

[0079] Appendix Figures 3A-3D This is a schematic cross-sectional view of the main process in forming the oxide layer according to a specific embodiment of the present invention. For example, the specific steps for forming the oxide layer 23 include: first, providing a reaction chamber 30, which has a support platform 31 and a spray head 32 located on the upper part of the reaction chamber 30. The spray head is connected to the air inlet channel 33. Before placing the capacitor substrate 21 into the reaction chamber 30, the support platform 31 used to support the capacitor substrate 21 is preheated to 25°C to 300°C. Figure 3A As shown. Then, the capacitor substrate 21 is placed on the surface of the support stage 31, and a mixed gas of O2, H2N2, and N2, or a mixed gas of O2, H2N2, and Ar, is introduced into the reaction chamber 30 through the air inlet channel 33. The dry etching gas is uniformly dispersed by the spray head 32 and then ionized by a radio frequency power of 100W to 10000W to form a mixed gas plasma including O2 plasma, H2N2 plasma, and N2 plasma, or a mixed gas plasma including O2 plasma, H2N2 plasma, and Ar plasma. This mixed gas plasma oxidizes the surface of the capacitor substrate 21, forming the oxide layer 23, as shown. Figure 3B As shown. In this step, the flow rate of the mixed gas plasma is 100 sccm to 15000 sccm, and the pressure of the mixed gas plasma is 10 mtorr to 10000 mtorr. By using the low-flow-rate, low-pressure dry etching gas, it is easier to control the oxidation endpoint and avoid over-oxidation of the capacitor transfer structure 211. Next, the reaction chamber 30 is continuously purged with N2 to bring the capacitor substrate 21 to room temperature, as shown. Figure 3C As shown. Then, the capacitor substrate 21 is removed from the reaction chamber 30.

[0080] Step S14: Remove the oxide layer 23 to expose the capacitor transfer structure 211, as shown below. Figure 2D As shown.

[0081] Optionally, the specific steps for removing the oxide layer 23 include:

[0082] Clean the capacitor substrate 21.

[0083] Optionally, the specific steps for cleaning the capacitor substrate 21 include:

[0084] The capacitor substrate 21 was cleaned using a DHF solution.

[0085] Optionally, the volume ratio of HF to H2O in the DHF solution is (10:1) to (1000:1). For example, the volume ratio of HF to H2O in the DHF solution is (10:1) to (50:1), (20:1) to (100:1), (200:1) to (800:1), or (500:1) to (1000:1), with a preferred volume ratio being (200:1) to (800:1).

[0086] Appendix Figures 4A-4E This is a schematic cross-sectional view of the main process in removing the oxide layer according to a specific embodiment of the present invention. For example, the specific steps of washing the capacitor substrate 21 include: firstly, spraying deionized water onto the oxide layer 23 on the capacitor substrate 21 through the first spray pipe 40 to wet the oxide layer 23, such as... Figure 4A As shown. Then, DHF (HF diluted with deionized water) solution is continuously sprayed onto the surface of the oxide layer 23 of the capacitor substrate 21 through the first spray nozzle 40, as... Figure 4B As shown, particulate contaminants and native oxides on the surface of the oxide layer 23 are removed, exposing the oxide layer 23.

[0087] Optionally, the specific steps for removing the oxide layer 23 include:

[0088] The oxide layer 23 was removed using a wet etching process.

[0089] Optionally, the specific steps for removing the oxide layer 23 using a wet etching process include:

[0090] A wet etchant with an etching selectivity of 10:1 or greater than or equal to that of the oxide layer 23 and the capacitor transfer structure 211 is used to remove the oxide layer 23.

[0091] Since the present embodiment unifies the components of the surface residual particles of the capacitor substrate 21 by oxidation, and the components of the oxidation layer 23 are different from the components of the capacitor adapter structure 211, the oxidation layer 23 can be removed sufficiently by selecting an etchant with a high etching selectivity for the oxidation layer 23 and the capacitor adapter structure 211, and no damage is caused to the capacitor adapter structure 211.

[0092] Optionally, the material of the capacitor adapter structure 211 is a metal material; and the specific steps of removing the oxidation layer 23 by using a wet etching process include:

[0093] An alkaline solution is used as the wet etchant to remove the oxidation layer 23.

[0094] Optionally, the specific steps of removing the oxidation layer 23 by using an alkaline solution as the wet etchant include:

[0095] An NH4OH and H2O mixed solution is used as the wet etchant to remove the oxidation layer 23.

[0096] Optionally, the volume ratio of NH4OH to H2O in the wet etchant is (5:1) to (1000:1). For example, the volume ratio of NH4OH to H2O in the wet etchant is (5:1) to (100:1), (20:1) to (200:1), (50:1) to (500:1), or (100:1) to (1000:1), and the preferable volume ratio is (50:1) to (500:1).

[0097] Optionally, after removing the oxidation layer 23, the method further includes the following steps:

[0098] The capacitor substrate 21 is dried.

[0099] Optionally, the specific steps of drying the capacitor substrate 21 include:

[0100] A mixed gas of nitrogen and isopropyl alcohol is used to purge the capacitor substrate 21.

[0101] The following is described by taking the material of the capacitor adapter structure 211 as tungsten and the material of the oxidation layer 23 as tungsten oxide as an example. First, the first spray pipe 40 is used to spray an ADM solution including NH4OH and H2O to the surface of the oxidation layer 23, as shown in FIG. 4A. Figure 4C The ADM solution can react with tungsten oxide but not with tungsten, and the etching selectivity of the ADM solution for tungsten oxide and tungsten is 50:1, so that the tungsten oxide can be removed sufficiently and no damage is caused to the tungsten. Then, the first spray pipe 40 is used to spray deionized water to the surface of the capacitor substrate 21 again, as shown in FIG. 4B. Figure 4DThe residual ADM solution is removed as shown. Next, a mixed gas of nitrogen and isopropyl alcohol is sprayed toward the surface of the capacitor substrate 21 by tilting the second spray pipe 41 in the arrow direction as shown in FIG. 4B. Figure 4E Figure 4E The residual water vapor is prevented from re-oxidizing the tungsten as shown.

[0102] Furthermore, the present embodiment also provides a semiconductor structure formed by the method for forming a semiconductor structure according to any one of the above.

[0103] The semiconductor structure and the method for forming a semiconductor structure provided by the present embodiment can oxidize the surface of the capacitor transfer structure and the conductive particles remaining on the surface of the capacitor transfer structure after the isolation layer is removed and the top surface of the capacitor transfer structure is exposed, so that the surface material of the capacitor substrate is uniform. After the oxidation layer is removed, the defects on the surface of the capacitor transfer structure and the particles remaining on the surface of the capacitor transfer structure and the surface of the isolation layer can be removed. The defects on the surface of the capacitor transfer structure are reduced, and the problem of short circuit between adjacent capacitor transfer structures is avoided, thereby improving the electrical performance of the semiconductor structure.

[0104] The above merely describes the preferred embodiments of the present application. It should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered within the protection scope of the present application.​

Claims

1. A method for forming a semiconductor structure, characterized in that, Includes the following steps: A capacitor substrate is formed, the capacitor substrate including a plurality of capacitor transfer structures and an isolation layer located between adjacent capacitor transfer structures and covering the top surface of the capacitor transfer structures; Remove the isolation layer covering the top surface of the capacitor transfer structure to expose the capacitor transfer structure; The material of the capacitor transfer structure is tungsten; The specific steps for removing the isolation layer covering the top surface of the capacitor transfer structure include: etching the isolation layer using a dry etching process; the material of the isolation layer is a nitride material; the specific steps for etching the isolation layer using a dry etching process further include: using a mixed gas of CF4, CHF3 and O2 as the etching gas to etch the isolation layer; after exposing the capacitor transfer structure, the tungsten material of the capacitor transfer structure is bombarded, and tungsten particles and tungsten oxide particles remain on the surface of the capacitor substrate; Oxidize the surface of the capacitor substrate that exposes the capacitor transfer structure to form an oxide layer; The specific steps of oxidizing the surface of the capacitor substrate that exposes the capacitor transfer structure include: The capacitor substrate is oxidized using O2 plasma to expose the surface of the capacitor transfer structure and the tungsten particle residue on the capacitor substrate. The residue remaining on the surface of the capacitor substrate and the top surface of the capacitor transfer structure both form the same oxide layer; Remove the oxide layer to expose the capacitor transfer structure.

2. The method for forming a semiconductor structure according to claim 1, characterized in that, The specific steps for forming a capacitor substrate include: A substrate is provided, wherein the substrate has a plurality of capacitive contact regions; Multiple capacitor transfer structures are formed on the surface of the substrate, and the multiple capacitor transfer structures are electrically connected to the multiple capacitor contact areas one by one. An isolation layer is formed to fill the gap between adjacent capacitor transfer structures and cover the top surface of the capacitor transfer structure.

3. The method for forming a semiconductor structure according to claim 1, characterized in that, The reaction temperature for oxidizing the surface of the capacitor substrate exposed by the capacitor transfer structure using O2 plasma is 25℃~300℃.

4. The method for forming a semiconductor structure according to claim 1, characterized in that, The specific steps of oxidizing the surface of the capacitor substrate exposing the capacitor transfer structure using O2 plasma include: A mixed gas plasma, comprising at least O2 plasma and H2N2 plasma, is transmitted to the surface of the capacitor substrate on which the capacitor transfer structure is exposed.

5. The method for forming a semiconductor structure according to claim 4, characterized in that, The flow rate of the mixed gas plasma is 100 sccm to 15000 sccm, and the pressure of the mixed gas plasma is 10 mtorr to 10000 mtorr.

6. The method for forming a semiconductor structure according to claim 4, characterized in that, The specific steps for transmitting a mixed gas plasma, comprising at least O2 plasma and H2N2 plasma, to the surface of the capacitor substrate on which the capacitor transfer structure is exposed include: A mixed gas containing O2 and H2N2 is ionized using radio frequency power ranging from 100W to 10000W to form a mixed gas plasma. The mixed gas plasma is transmitted to the surface of the capacitor substrate on which the capacitor transfer structure is exposed.

7. The method for forming a semiconductor structure according to claim 1, characterized in that, The specific steps for removing the oxide layer include: Clean the capacitor substrate.

8. The method for forming a semiconductor structure according to claim 7, characterized in that, The specific steps for cleaning the capacitor substrate include: The capacitor substrate was cleaned using a DHF solution.

9. The method for forming a semiconductor structure according to claim 8, characterized in that, The volume ratio of HF to H2O in the DHF solution is (10:1) to (1000:1).

10. The method for forming a semiconductor structure according to claim 1, characterized in that, The specific steps for removing the oxide layer include: The oxide layer was removed using a wet etching process.

11. The method for forming a semiconductor structure according to claim 10, characterized in that, The specific steps for removing the oxide layer using a wet etching process include: A wet etchant with an etching selectivity greater than or equal to 10:1 is used to remove the oxide layer and the capacitor transfer structure.

12. The method for forming a semiconductor structure according to claim 10, characterized in that, The capacitor transfer structure is made of a metallic material; The specific steps for removing the oxide layer using a wet etching process include: The oxide layer was removed using an alkaline solution as a wet etching agent.

13. The method for forming a semiconductor structure according to claim 12, characterized in that, The specific steps for removing the oxide layer using an alkaline solution as a wet etching agent include: The oxide layer was removed using a mixed solution of NH4OH and H2O as a wet etching agent.

14. The method for forming a semiconductor structure according to claim 13, characterized in that, The volume ratio of NH4OH to H2O in the wet etching agent is (5:1) to (1000:1).

15. The method for forming a semiconductor structure according to claim 1, characterized in that, After removing the oxide layer, the process further includes the following steps: Dry the capacitor substrate.

16. The method for forming a semiconductor structure according to claim 15, characterized in that, The specific steps for drying the capacitor substrate include: The capacitor substrate is purged with a mixture of nitrogen and isopropanol.

17. A semiconductor structure, characterized in that, The semiconductor structure is formed using the method described in any one of claims 1-16.

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