WO2023279648A1

WO2023279648A1 - Manufacturing method for semiconductor structure, semiconductor structure, and memory

Info

Publication number: WO2023279648A1
Application number: PCT/CN2021/135726
Authority: WO
Inventors: 张春雷
Original assignee: 长鑫存储技术有限公司
Priority date: 2021-07-09
Filing date: 2021-12-06
Publication date: 2023-01-12
Also published as: CN113517170B; CN113517170A

Abstract

Provided in the present disclosure are a manufacturing method for a semiconductor structure, a semiconductor structure, and a memory. The manufacturing method for a semiconductor structure comprises: providing a substrate and a reaction chamber, the substrate being placed in the reaction chamber; forming a silicon nitride layer on the substrate; and forming a polysilicon layer on the silicon nitride layer; after forming the silicon nitride layer and before forming the polysilicon layer, the inner surface of the reaction chamber and the surface of the silicon nitride layer are treated with dissociated nitrogen gas to reduce nitrogen-hydrogen bonding on the surface of the silicon nitride layer.

Description

Manufacturing method of semiconductor structure, semiconductor structure and memory

This disclosure claims the priority of the Chinese patent application with the application number 202110778391.X and the invention title "Manufacturing method of semiconductor structure, semiconductor structure and memory" submitted to the China Patent Office on July 09, 2021, the entire contents of which are incorporated by reference incorporated in this disclosure.

technical field

The present disclosure includes but is not limited to a method of manufacturing a semiconductor structure, a semiconductor structure and a memory.

Background technique

A memory generally includes a capacitor and a transistor, wherein the capacitor is used to store data, and the transistor is used to control access to the data stored in the capacitor. Specifically, in the manufacturing process of the memory, the structure of the capacitor and the transistor can be formed by stacking multiple film layers on the wafer.

At present, in the process of silicon nitride and polysilicon double-layer film deposition, due to the poor adhesion of the contact surface of silicon nitride film and polysilicon, in the process of film deposition in the reaction chamber by vapor deposition method, due to the gravity The film adhered to the shower head and the wall of the reaction chamber will fall off and fall on the wafer to form defects.

It should be noted that the information disclosed in the above background section is only for enhancing the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to those skilled in the art.

Contents of the invention

The following is an overview of the subject matter described in detail in this disclosure. This summary is not intended to limit the scope of the claims.

According to one aspect of the present disclosure, there is provided a method of manufacturing a semiconductor structure, the method of manufacturing the semiconductor structure comprising:

providing a substrate and a reaction chamber, the substrate being placed in the reaction chamber;

forming a silicon nitride layer on the substrate;

forming a polysilicon layer on the silicon nitride layer;

Wherein, after forming the silicon nitride layer and before forming the polysilicon layer, the inner surface of the reaction chamber and the surface of the silicon nitride layer are treated with dissociated nitrogen gas to reduce the nitrogen Nitrogen-hydrogen bonding on the surface of the silicon oxide layer.

According to another aspect of the present disclosure, there is also provided a semiconductor structure formed by the above-mentioned manufacturing method.

According to still another aspect of the present disclosure, there is also provided a memory, which includes the above-mentioned semiconductor structure

Other aspects will be apparent to others upon reading and understanding the drawings and detailed description.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with the description, serve to explain principles of the embodiments of the disclosure. In the drawings, like reference numerals are used to denote like elements. The drawings in the following description are some, but not all, embodiments of the present disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without any creative work.

One or more embodiments are exemplified by the pictures in the corresponding drawings, and these exemplifications do not constitute a limitation to the embodiments. Elements with the same reference numerals in the drawings represent similar elements. Unless otherwise stated, the drawings in the drawings are not limited to scale.

FIG. 1 is a flowchart of a method for manufacturing a silicon nitride layer provided by an embodiment of the present disclosure;

Fig. 2 is the schematic diagram of the reaction chamber adopting the manufacturing method of the silicon nitride layer provided;

3 is a schematic diagram of a reaction chamber of a method for manufacturing a silicon nitride layer in the related art;

Fig. 4 is an enlarged view of area A in Fig. 3;

FIG. 5 is a schematic diagram of the comparison between the force between the molecules of the silicon nitride layer and the polysilicon layer and the force between the molecules of the silicon nitride layer and the polysilicon layer in the related art;

6-10 are schematic diagrams of the manufacturing process for forming a semiconductor structure including a silicon nitride layer and a polysilicon layer in the related art;

11-15 are schematic diagrams of the manufacturing process for forming a semiconductor structure including a silicon nitride layer and a polysilicon layer provided by the present disclosure;

FIG. 16 is a schematic diagram showing a comparison of gas and frequency parameters used in forming a silicon nitride layer in the related art and gas and frequency used in forming a silicon nitride layer in the present disclosure.

detailed description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed descriptions will be omitted.

An embodiment of the present disclosure provides a method for manufacturing a semiconductor structure. As shown in FIG. 1 , the method for manufacturing the semiconductor structure includes:

Step S100, providing a substrate and a reaction chamber, where the substrate is placed in the reaction chamber;

Step S200, forming a silicon nitride layer on the substrate;

Step S300, using dissociated nitrogen gas to treat the inner surface of the reaction chamber and the surface of the silicon nitride layer, so as to reduce nitrogen-hydrogen bonding on the surface of the silicon nitride layer;

Step S400, forming a polysilicon layer on the processed silicon nitride layer.

In the related technology, as shown in Fig. 3, Fig. 6-Fig. 10, during the formation process of the silicon nitride layer and the polysilicon layer, a silicon nitride layer (SiN) 510, a polysilicon layer are formed on the inner wall of the reaction chamber and the shower head. (A-Si) 520 and seasoning layer (Season film) 530, because the contact surface adhesiveness of silicon nitride layer 510 and polysilicon layer 520 is poor, cause under the action of gravity to stick on the shower head and reaction chamber inner wall Defects formed on a wafer by film shedding.

In the method for manufacturing a silicon nitride layer provided in the present disclosure, the surface of the silicon nitride layer is treated with nitrogen ions formed after dissociation of nitrogen gas, which reduces the nitrogen-hydrogen bonding on the surface of the silicon nitride layer, thereby improving the nitrogen The adhesiveness of silicon oxide layer and polysilicon layer, as shown in Figure 2, the film on shower head and reaction chamber inner wall can not come off the defect that forms on wafer (Wafer) 540,

Next, each step in the manufacturing method of the silicon nitride layer provided by the present disclosure will be described in detail.

In step S100, a substrate and a reaction chamber are provided, and the substrate is placed in the reaction chamber.

As shown in FIG. 2, a substrate and a reaction chamber are provided, and the substrate is placed in the reaction chamber. Wherein, the substrate may be the wafer 540 shown in FIG. 2 .

In step S200, a silicon nitride layer is formed on the substrate.

A silicon nitride layer 510 is formed on the wafer 540 , and the silicon nitride layer 510 is formed on the shower head and the inner wall of the reaction chamber at the same time. After the silicon nitride layer is formed, the surface has nitrogen-hydrogen bonding.

The main reaction of silicon nitride layer formation is:

SiH ₄ +NH ₃ +e-+N ₂ →Si-H ₃ +N-H+N+N ₂

N+SiH ₃ →NH+SiH _x

N-H+SiH _x →Si _x N _y +H ₂

The side reactions of silicon nitride layer formation are:

NH _x +Si-H _x →Si _x N _y -H _z +H ₂

The silicon nitride structure is:

The main reaction of polysilicon layer formation is:

SiH ₄ +H _e +e ^- → Si-H ₂ +H ₂ +H _e

Si-H ₂ +H _e +e ^- →Si-H+H ₂ +H _e

Si-H+H _e +e ^- → A-Si+H ₂ +H _e

The side reactions of polysilicon layer formation are:

SiH ₂ +H _e +e-→Si-H+H ₂ +H _e

The polysilicon structure is:

According to the reaction process and structure of the formation of the silicon nitride layer and the reaction process and structure of the formation of the polysilicon layer, it can be seen that in the deposition process of the silicon nitride layer, due to the existence of side reactions, the deposited silicon nitride layer contains a small amount of N-H bonding and Si-H bonding, and in the subsequent polysilicon layer deposition process, the existence of side reactions will lead to a small amount of Si-H in the resulting polysilicon film, according to the principle of similar miscibility, as shown in Figure 5 , two solids with similar structures, the intermolecular force (van der Waals force) will become larger; therefore, the silicon nitride layer containing more Si-H bonds is easy to adhere to the polysilicon containing Si-H bonds; on the contrary, nitrogen The silicon oxide layer contains more N-H bonds, which is not suitable for adhering to the polysilicon layer containing Si-H.

Therefore, the main reason for the poor adhesion between the silicon nitride layer and the polysilicon layer is that the silicon nitride layer contains more N-H bonds, as shown in Figure 4, the existence of these N-H bonds makes the silicon nitride layer and the polysilicon layer The adhesion between the polysilicon layer subsequently formed on its surface becomes poor. Due to the poor adhesion of the interface between the silicon nitride layer and the polysilicon layer, during the process of film deposition in the reaction chamber by vapor deposition In the process, due to the action of gravity, the film adhered to the shower head and the wall of the reaction chamber will fall off, thus falling on the wafer to form defects.

In one embodiment of the present disclosure, the silicon nitride layer is formed by chemical vapor deposition process according to silane (SiH ₄ ), ammonia (NH ₃ ) and nitrogen (N ₂ ); wherein, the flow ratio of silane and ammonia is: 1.3-10, such as 1.3, 1.33, 1.5, 2, 5, 8, or 10, etc., are not listed here; of course, the flow ratio of silane to ammonia can also be less than 1.3 or greater than 10, and this disclosure does not limit. By adjusting the flow ratio of silane and ammonia to 1.3-10, the deposition process of the silicon nitride layer is optimized, and the NH bond in the silicon nitride layer can be reduced.

Wherein, the flow rate of silane can be 200 sccm-500 sccm, such as 200 sccm, 300 sccm, 400 sccm or 500 sccm, etc., which are not listed here; of course, the flow rate of silane can also be less than 200 sccm or greater than 500 sccm, which is not limited in the present disclosure.

Wherein, the flow rate of ammonia gas is 50 sccm-250 sccm, such as 50 sccm, 100 sccm, 150 sccm, 200 sccm or 250 sccm, etc., which are not listed one by one here; of course, the flow rate of ammonia gas can also be less than 50 sccm or greater than 250 sccm, which is not disclosed in the present disclosure. Do limit.

Wherein, the flow rate of nitrogen can be 15000sccm-25000sccm, such as 15000sccm, 18000sccm, 20000sccm, 22000sccm or 25000sccm, etc., which are not listed here; of course, the flow rate of nitrogen gas can also be less than 15000sccm or greater than 25000sccm, and this disclosure does not limit.

Among them, through the radio frequency chemical vapor deposition method, various reaction gases for forming the silicon nitride layer are ejected, and the radio frequency power during the reaction process can be 400W-1000W, such as 400W, 500W, 600W, 700W, 800W, 900W or 1000W etc. are not listed here; of course, the radio frequency power may also be less than 400W or greater than 1000W, which is not limited in this disclosure.

The present disclosure improves the formation process of the silicon nitride layer by adjusting the ratio of _SiH4 and _NH3 , and improving the deposition process to adjust the radio frequency power, and the double-layer film adhesion of the silicon nitride layer and the polysilicon layer is relatively better, During the deposition process of the polysilicon layer, the thin film will not fall off, so the surface flaky defects of the double-layer thin film of the silicon nitride layer and the polysilicon layer are obviously reduced, and the process reliability is improved.

In step S300, the inner surface of the reaction chamber and the surface of the silicon nitride layer are treated with dissociated nitrogen gas to reduce nitrogen-hydrogen bonding on the surface of the silicon nitride layer.

The nitrogen is dissociated by the inert gas, and the use of the inert gas can avoid other side reactions after the inert gas dissociates the nitrogen, and improves the reliability of dissociation of the nitrogen. Wherein, the inert gas may be at least one of argon and helium, for example.

Wherein, the flow ratio of the inert gas to the nitrogen is 0.2-1, and the dissociation of the nitrogen can be better achieved by making the flow ratio of the inert gas to the nitrogen 0.2-1. For example, the flow ratio can be 0.20, 0.3, 0.5, 0.7, 0.8, 1, etc., which are not listed here; of course, the flow ratio of inert gas to nitrogen can also be less than 0.2 or greater than 1, which is not limited in the present disclosure.

Wherein, the flow rate of the inert gas is 5000 sccm-15000 sccm, and the flow rate of the nitrogen gas is 15000 sccm-25000 sccm. The flow rate of the inert gas can be, for example, 5000 sccm, 8000 sccm, 1000 sccm, 12000 sccm or 15000 sccm, etc., which are not listed here; of course, the flow rate of the inert gas can also be less than 5000 sccm or greater than 15000 sccm, and the present disclosure is not limited here. The flow rate of nitrogen gas can be, for example, 15000 sccm, 18000 sccm, 20000 sccm, 22000 sccm or 25000 sccm, etc., which are not listed here; of course, the flow rate of nitrogen gas can also be less than 15000 sccm or greater than 25000 sccm, which is not limited in this disclosure.

Wherein, the flow rate of inert gas is 5000sccm-15000sccm, and when the inert gas is argon or helium, the flow rate of argon or helium is 5000sccm-15000sccm; when the inert gas is a mixed gas of argon and helium, The flow rate of the mixed gas of argon and helium is 5000sccm-15000sccm; in the mixed gas of argon and helium, the flow ratio of argon and helium can be determined according to specific conditions, which is not limited in the present disclosure.

Among them, when the nitrogen gas is dissociated by the inert gas, the plasma generating device bombards the nitrogen gas with the inert gas, and the radio frequency power of the plasma generating device is 400W-1000W during the processing, so as to ensure the dissociation of the nitrogen gas by the inert gas Effect. Wherein, the radio frequency power can be, for example, 400W, 500W, 600W, 700W, 800W, 900W, or 1000W, etc., which are not listed here; of course, the radio frequency power can also be less than 400W or greater than 1000W, which is not limited in this disclosure.

After nitrogen is dissociated by inert gas, multiple nitrogen ions are formed, and the nitrogen ions react with N-H bonds, thereby reducing the number of N-H bonds and avoiding the existence of N-H bonds. The adhesion between the polysilicon layer on the surface becomes poor, thereby avoiding the adhesion on the shower head and the inner wall of the reaction chamber under the action of gravity due to the poor adhesion of the contact surface of the silicon nitride layer and the polysilicon layer The thin film comes off the defect formed on the wafer.

In one embodiment of the present disclosure, as shown in FIG. 16 , forming the silicon nitride layer includes: continuously feeding silane, ammonia gas and nitrogen gas into the reaction chamber _; The radio frequency power of the body generating device is adjusted to the first preset radio frequency power; after the _second preset time T2, the silane and ammonia gas are suspended to form a silicon nitride layer; nitrogen and inert gas are continued to be introduced into the reaction chamber Gas, adjust the radio frequency power of the plasma generator to the second preset radio frequency power, and use the plasma generator to bombard the nitrogen with the inert gas to dissociate the nitrogen; use the dissociated nitrogen to treat the inner surface of the reaction chamber and The surface of the silicon nitride layer; after the _third preset time T3, stop feeding nitrogen and inert gas, and the radio frequency power of the plasma generating device is adjusted to zero

Wherein, the first preset radio frequency power can be the radio frequency power in the process of ejecting various reaction gases for forming the silicon nitride layer by the radio frequency chemical vapor deposition method, and the second preset radio frequency power can be the radio frequency power used by the above plasma generation device. Moderate RF power in the process of bombarding nitrogen with inert gas; as shown in Figure 16, since the RF power is 400W-1000W from the Dep1 stage to the plasma purge stage, the first preset RF power and the second preset RF power are The same can be used to reduce the number of adjustments to the radio frequency power of the plasma generating device and improve the efficiency of the manufacturing process.

Wherein, the first preset time T ₁ , the second preset time T ₂ and the third preset time T ₃ are the time required for the respective corresponding reaction processes, and the specific time depends on the specific circumstances, and this disclosure does not make any limit.

As shown in FIGS. 11-15 , the first carbon wafer 620 is located on the base substrate 610, the silicon nitride layer 510 is formed on the first carbon wafer 620, the polysilicon layer 520 is formed on the silicon nitride layer 510, and the second The second carbon wafer 630 is located on the polysilicon layer 520, the silicon oxide layer 640 is located on the second carbon wafer 630, and the photoresist layer 650 is formed on the silicon oxide layer 640, through the etching material 660 and the patterned photoresist Layer 650 etches the underlying film layers. As shown in Figures 6-10, in the formation process of the related technology, there is a peeling film on the polysilicon layer 520, which affects the subsequent film deposition; as shown in Figures 11-15, the nitriding provided by the present disclosure After the manufacturing method of the silicon layer, there is no shedding film on the polysilicon layer 520, which will not affect the subsequent film deposition, which improves the reliability of the process, improves the product yield, reduces the production cost, and improves the production efficiency.

Step S400, forming a polysilicon layer on the processed silicon nitride layer.

The polysilicon layer may be formed by a chemical vapor deposition process based on silane ( _SiH ₄ ) and helium (He ). Those skilled in the art may also use other methods to form the polysilicon layer, which is not limited in the present disclosure.

In the method for manufacturing a silicon nitride layer provided in the present disclosure, on the one hand, the surface of the silicon nitride layer is treated with nitrogen ions formed after dissociation of nitrogen gas, and the surface of the silicon nitride layer is passivated. The nitrogen-hydrogen bonding on the surface of the silicon nitride layer is reduced, so that the adhesion with the subsequently formed polysilicon layer can be improved, and the adhesion caused by the poor contact surface of the silicon nitride layer and the polysilicon layer is avoided. Under the action, the thin film adhered to the shower head and the inner wall of the reaction chamber falls off to form defects on the wafer; on the other hand, by adjusting the ratio of SiH ₄ and NH ₃ and improving the deposition process to adjust the RF power, the silicon nitride layer The improvement of the formation process further improves the reliability of the process.

The implementation of the present disclosure also provides a semiconductor structure formed by the above-mentioned manufacturing method of the semiconductor structure. The semiconductor structure provided by the present disclosure reduces the nitrogen-hydrogen bonding in the silicon nitride layer, thereby improving the adhesion with the polysilicon layer, avoiding the poor adhesion between the silicon nitride layer and the polysilicon layer. It is a defect formed on the wafer that causes the thin film adhered to the shower head and the inner wall of the reaction chamber to fall off under the action of gravity. For more details and beneficial effects, please refer to the above related descriptions about the embodiment of the manufacturing method of the semiconductor structure, which will not be repeated here.

The implementation of the present disclosure also provides a memory, which includes the above-mentioned semiconductor structure. The semiconductor structure can be applied to various memories, such as computing memory (for example, DRAM, SRAM, DDR3SDRAM, DDR2SDRAM, DDRSDRAM, etc.), consumer memory (for example, DDR3SDRAM, DDR2SDRAM, DDRSDRAM, SDRSDRAM, etc.), graphics memory (For example, DDR3SDRAM, GDDR3SDMRA, GDDR4SDRAM, GDDR5SDRAM, etc.), mobile memory, etc., the beneficial effects of which can refer to the above-mentioned narration about the manufacturing method of the semiconductor structure, and will not be repeated here.

It should be noted that although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that these steps must be performed in this specific order, or that all shown steps must be performed to achieve achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step for execution, and/or one step may be decomposed into multiple steps for execution, etc.

In the description of this specification, descriptions with reference to the terms "embodiments", "exemplary embodiments", "some implementations", "exemplary implementations", "examples" and the like mean that the descriptions are described in conjunction with the implementations or examples. A specific feature, structure, material, or characteristic is included in at least one embodiment or example of the present disclosure.

In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

In the description of the present disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation are therefore not to be construed as limitations on the present disclosure.

The terms 'first', 'second', etc. used in the present disclosure may be used to describe various structures in the present disclosure, but the structures are not limited by these terms. These terms are only used to distinguish one structure from another.

In one or more drawings, like elements are indicated with like reference numerals. For the sake of clarity, various parts in the drawings are not drawn to scale. Also, some well-known parts may not be shown. For simplicity, the structure obtained after several steps can be described in one figure. In the following, many specific details of the present disclosure, such as structures, materials, dimensions, processing techniques and techniques of devices, are described for a clearer understanding of the present disclosure. However, as will be understood by those skilled in the art, the present disclosure may be practiced without these specific details.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present disclosure, not to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some or all of the technical features; these modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present disclosure.

Industrial Applicability

In the manufacturing method of the semiconductor structure provided by the embodiments of the present disclosure, the nitrogen ions formed after the dissociation of nitrogen gas are used to treat the surface of the silicon nitride layer, which reduces the nitrogen-hydrogen bonding on the surface of the silicon nitride layer, thereby improving The adhesion to the polysilicon layer avoids the defect that the thin film adhered to the nozzle and the inner wall of the reaction chamber under the action of gravity falls off on the wafer due to the poor adhesion of the contact surface between the silicon nitride layer and the polysilicon layer .

Claims

A manufacturing method of a semiconductor structure, the manufacturing method comprising:

providing a substrate and a reaction chamber, the substrate being placed in the reaction chamber;

forming a silicon nitride layer on the substrate;

forming a polysilicon layer on the silicon nitride layer;

Wherein, after forming the silicon nitride layer and before forming the polysilicon layer, the inner surface of the reaction chamber and the surface of the silicon nitride layer are treated with dissociated nitrogen gas to reduce the nitrogen Nitrogen-hydrogen bonding on the surface of the silicon oxide layer.
The manufacturing method according to claim 1, wherein the treating the inner surface of the reaction chamber and the surface of the silicon nitride layer with dissociated nitrogen gas further comprises:

The nitrogen is bombarded with an inert gas to dissociate the nitrogen.
The manufacturing method according to claim 2, wherein the inert gas comprises: at least one of argon and helium.
The manufacturing method according to claim 2 or 3, wherein the flow ratio of the inert gas to the nitrogen gas is 0.2-1.
The manufacturing method according to claim 2 or 3, wherein the flow rate of the inert gas is 5000 sccm-15000 sccm, and the flow rate of the nitrogen gas is 15000 sccm-25000 sccm.
The manufacturing method according to claim 2, wherein the nitrogen gas is bombarded by the inert gas through a plasma generating device, and the radio frequency power is 400W-1000W.
The manufacturing method according to claim 1, wherein said forming a silicon nitride layer comprises:

The silicon nitride layer is formed by chemical vapor deposition process according to silane, ammonia gas and nitrogen gas; wherein, the flow ratio of the silane gas to the ammonia gas is 1.3-10.
The manufacturing method according to claim 7, wherein the flow rate of the silane is 200 sccm-500 sccm, and the flow rate of the ammonia gas is 50 sccm-250 sccm.
The manufacturing method according to claim 7, wherein the flow rate of the nitrogen gas is 15000 sccm-25000 sccm.
The manufacturing method according to claim 1, wherein said forming a silicon nitride layer comprises:

Introducing silane, ammonia and nitrogen into the reaction chamber;

After the first preset time, the radio frequency power of the plasma generating device is adjusted to the first preset radio frequency power;

After a second preset time, suspending the introduction of the silane and the ammonia gas to form a silicon nitride layer;

Continue to feed the nitrogen gas and the inert gas into the reaction chamber at the same time, adjust the radio frequency power of the plasma generator to the second preset radio frequency power, and make the inert gas react to the reaction chamber through the plasma generator. The nitrogen is bombarded to dissociate the nitrogen;

The inner surface of the reaction chamber and the surface of the silicon nitride layer are treated with the dissociated nitrogen gas.
The manufacturing method according to claim 10, wherein said forming a silicon nitride layer further comprises:

After the third preset time, stop feeding the nitrogen gas and the inert gas, and adjust the radio frequency power of the plasma generating device to zero.
The manufacturing method according to claim 10, wherein the first preset radio frequency power is the same as the second preset radio frequency power.
The manufacturing method according to claim 10, wherein the flow ratio of the silane to the ammonia is 1.3-10.
A semiconductor structure formed by the manufacturing method according to any one of claims 1-13.
A memory comprising the semiconductor structure of claim 14.