CN110396676B

CN110396676B - Atomic layer deposition equipment and method

Info

Publication number: CN110396676B
Application number: CN201810372755.2A
Authority: CN
Inventors: 赵雷超; 史小平; 李春雷; 秦海丰; 纪红; 张文强
Original assignee: Beijing Naura Microelectronics Equipment Co Ltd
Current assignee: Beijing Naura Microelectronics Equipment Co Ltd
Priority date: 2018-04-24
Filing date: 2018-04-24
Publication date: 2021-07-13
Anticipated expiration: 2038-04-24
Also published as: CN110396676A

Abstract

The invention discloses atomic layer deposition equipment and a method, and the equipment comprises a reaction chamber, a tail gas treatment device, a plurality of transmission pipelines, a plurality of tail gas treatment pipelines, a plurality of purging branches and a plurality of precursor source bottles, wherein each transmission pipeline is connected to the reaction chamber so as to selectively introduce corresponding precursors into the reaction chamber; each tail gas treatment pipeline is connected to a tail gas treatment device and is connected with one transmission pipeline through a corresponding purging branch; each tail gas treatment pipeline is selectively communicated with a tail gas treatment device or a transmission pipeline. According to the invention, the purging bypass is added, the flow of the purging gas is increased, the purging time can be effectively reduced, the equipment productivity is improved, and the cost is saved; and moreover, a purging mode of a gradient airflow field is adopted, so that the removal of residual precursors or particles is facilitated, process particles are avoided, and the quality of the film is improved.

Description

Atomic layer deposition equipment and method

Technical Field

The invention relates to the field of semiconductor integrated circuit manufacturing, in particular to atomic layer deposition equipment and an atomic layer deposition method.

Background

With the development of semiconductor technology, the feature size of devices is gradually reduced, and higher requirements are put on the performance of deposited films, especially on the aspects of film thickness control and uniformity indexes. The disadvantages of conventional thin film Deposition techniques, such as Physical Vapor Deposition (PVD) and Chemical Vapor Deposition (CVD), are more and more obvious in the aspect of controlling the thickness and uniformity of the thin film, especially in the application field with higher requirements for step coverage. The film prepared by the Atomic Layer Deposition (ALD) technology has highly controllable thickness and excellent uniformity, and completely makes up the defects of the traditional film process. In addition, the atomic layer deposition technique has many advantages such as low deposition temperature, diversified substrate types, and excellent step coverage. Therefore, the attention of people is increasingly paid.

The atomic layer deposition technology is a coating method which leads gas phase reaction precursors into a reaction chamber one by one in a pulse and alternative mode, and leads inert gas to sweep among the precursors so as to isolate different precursors and lead substances to be adsorbed on the surface of a substrate layer by layer in a monoatomic film mode. The atomic layer deposition is characterized by self-limitation, that is, after the active sites on the surface of the substrate are consumed, no adsorption or reaction occurs, and the excess reaction precursor is purged out of the reaction chamber by the inert gas, which also determines that the thin film prepared by the atomic layer deposition technology has the characteristics of excellent conformality, good uniformity, high purity and the like. In addition, the atomic layer deposition technology can also accurately control the thickness of the film by controlling the reaction cycle number.

Since the ald technique has many advantages as mentioned above, it is often applied to the situation with smaller feature size, and therefore, the number of particles will become one of the key parameters for measuring the quality of the ald film. During the atomic layer deposition process, particles mainly originate from two aspects: 1) the process particles are particles, namely, in the process, partial precursors cannot be completely purged due to factors such as short gas purging time or insufficient flow and the like, and the partial precursors remain in a transmission pipeline or a cavity and react with another precursor to generate particles; 2) mechanical particles, i.e. particles generated by the frequent action of the butterfly valve core or the corrosion of metal parts by partial precursor residues when the control valve is a pneumatic valve in the process. These particles will seriously affect the yield of the fabricated device and increase the production cost.

FIG. 1 is a flow chart of a conventional ALD process. A complete ALD cycle consists essentially of two half-reactions: the first half reaction is that the first precursor is introduced into the cavity in a gas phase mode, and after the substrate surface is saturated and adsorbed or reacts, the excess reaction precursor is swept out of the cavity by using inert gas; and the second half reaction is to introduce a second precursor into the chamber, and introduce inert gas to blow the excess second precursor out of the chamber after the second precursor and substrate surface groups are subjected to saturated adsorption or reaction. And finally, judging whether the set circulation times are reached through the controller, and determining whether to continue circulation or finish the process.

Fig. 2 is a schematic diagram of a typical atomic layer deposition apparatus in the prior art, and fig. 3 is a graph showing the trend of chamber pressure over time during thin film deposition based on the atomic layer deposition apparatus shown in fig. 2. As can be seen from fig. 3, the chamber pressure is constant during the film deposition process, and a stable gas flow field is formed in the transfer line and the chamber, which is not favorable for purging the residual precursor or particles. In addition, the low flow rate of the purge gas is not conducive to clean removal of the residual precursor or particles, and the chemical reaction between a portion of the residual precursor and another precursor will generate a large amount of process particles to affect the film performance. In addition, the control valve in the prior art usually adopts a butterfly valve working in a constant pressure process mode, the opening of the control valve is controlled by means of constant pressure, and the control valve is easily influenced by the change of gas purging flow in the film deposition process, so that the valve core acts frequently, and mechanical particles are easily generated.

Therefore, there is a need for an atomic layer deposition apparatus and method that reduces process particles and mechanical particles.

The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Disclosure of Invention

The invention aims to provide atomic layer deposition equipment and a method, which are used for solving the problems that a stable airflow field is formed due to constant chamber pressure and the flow of purge gas is low in the film deposition process in the prior art.

According to an aspect of the present invention, an atomic layer deposition apparatus is provided, which includes a reaction chamber, an exhaust gas treatment device, a plurality of transmission lines, a plurality of exhaust gas treatment lines, a plurality of purge branches, and a plurality of precursor source bottles,

each precursor source bottle is correspondingly connected into one transmission pipeline, and each transmission pipeline is connected to the reaction chamber so as to selectively introduce the corresponding precursor into the reaction chamber;

each tail gas treatment pipeline is connected to the tail gas treatment device, and each tail gas treatment pipeline is connected with one transmission pipeline through the corresponding purging branch;

each tail gas treatment pipeline is selectively communicated with the tail gas treatment device or the corresponding transmission pipeline.

Preferably, each of the exhaust gas treatment lines is in selective communication with the exhaust gas treatment device or the transfer line through a first valve assembly;

the first valve assembly includes:

the first control valve is arranged on the purging branch;

and the second control valve is arranged on the tail gas treatment pipeline and is positioned between the inlet of the first control valve and the tail gas treatment device.

Preferably, each of the delivery lines selectively passes the corresponding precursor into the reaction chamber through a second valve assembly;

the second valve assembly includes:

a third control valve provided on the transfer line;

the fourth control valve is arranged on a connecting pipeline between the inlet of the third control valve and the inlet of the precursor source bottle;

and the fifth control valve is arranged on a connecting pipeline between the outlet of the third control valve and the outlet of the precursor source bottle.

Preferably, each inlet of the transmission pipeline is provided with a first mass flow controller, and each inlet of the tail gas treatment pipeline is provided with a second mass flow controller.

Preferably, the atomic layer deposition equipment further comprises a vacuum pump, the vacuum pump is connected with the reaction chamber through a butterfly valve, and a valve core of the butterfly valve is in a constant angle mode.

According to another aspect of the present invention, there is provided an atomic layer deposition method for atomic layer deposition using the atomic layer deposition apparatus as described above, including the steps of:

step 1, inert gas entering from one of the transmission pipelines carries precursors and then enters a reaction chamber, the inert gas entering from each tail gas treatment pipeline is discharged into a tail gas treatment device, and the inert gas entering from other transmission pipelines directly enters the reaction chamber;

step 2, the inert gas entering from each transmission pipeline is converged with the inert gas entering from the corresponding purging branch into the transmission pipeline, and enters the reaction chamber together for primary purging;

step 3, directly feeding the inert gas fed from each transmission pipeline into the reaction chamber for secondary purging, and discharging the inert gas fed from each tail gas treatment pipeline into the tail gas treatment device;

step 4, repeating the steps 1to 3 for a plurality of times;

and 5, judging whether the repetition times in the step 4 reach the set cycle times, if so, ending the process, otherwise, returning to the step 1. Preferably, in the step 1, the third control valve on one of the transmission pipelines is closed, the fourth control valve and the fifth control valve are opened, the third control valves on the other transmission pipelines are opened, the second control valve on each tail gas treatment pipeline is opened, and all the other control valves are closed; in the step 2, the third control valve on each transmission pipeline is opened, the first control valve on each purging branch is opened, and all the other control valves are closed; in the step 3, the third control valve on each transmission pipeline is opened, the second control valve on each tail gas treatment pipeline is opened, and all the other control valves are closed. Preferably, the butterfly valve operates in a constant angle mode. Preferably, before said step 4, the following steps are performed: and 3.1, repeatedly executing the step 2 and the step 3 for multiple times. Preferably, in the step 4, each time the steps 1to 3 are performed, an inert gas is used to carry a different precursor into the reaction chamber.

The invention has the following beneficial technical effects: by increasing the purging bypass, the flow of the purging gas is increased, the purging time can be effectively reduced, the equipment capacity is improved, and the cost is saved; and moreover, a purging mode of a gradient airflow field is adopted, so that the removal of residual precursors or particles is facilitated, process particles are avoided, and the quality of the film is improved. The method of the present invention has other features and advantages which will be apparent from or are set forth in detail in the accompanying drawings and the following detailed description, which are incorporated herein, and which together serve to explain certain principles of the invention.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings, in which like reference numerals generally represent like parts.

FIG. 1 shows a flow diagram of a prior art atomic layer deposition process;

FIG. 2 shows a schematic diagram of a typical prior art atomic layer deposition apparatus;

FIG. 3 is a graph showing a trend of chamber pressure during an atomic layer deposition process using the apparatus of FIG. 2;

FIG. 4 shows a schematic view of an atomic layer deposition apparatus according to an exemplary embodiment of the invention;

FIG. 5 shows a flow diagram of an atomic layer deposition process employed by the apparatus of FIG. 4;

FIG. 6 is a graph showing a trend of chamber pressure during an atomic layer deposition process using the apparatus of FIG. 4.

Description of the main reference numerals:

1-a reaction chamber, 2-a spray header, 3-a base, 4-a substrate, 5, 6-a precursor source bottle, 7-a control valve and 8-a vacuum pump;

11. 12-inert gas, 21, 22-first mass flow controller, 33, 36-third control valve, 31, 34-fourth control valve, 32, 35-fifth control valve, 41, 42-transmission line, 51, 52-second valve assembly;

13. 14-inert gas, 23, 24-second mass flow controller, 37, 38-first control valve, 39, 40-second control valve, 45, 46-purging branch, 47, 48-tail gas treatment line, 53, 54-first valve component, 10-tail gas treatment device.

Detailed Description

The invention provides a novel atomic layer deposition process realization method, which is characterized in that the pressure gradual change process in the purging step is generated by increasing the gas flow of the purging pipeline so as to realize the removal of residual precursors and reduce the generation of process particles, thereby ensuring the quality of deposited films.

The invention will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be 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 scope of the disclosure to those skilled in the art.

Fig. 4 shows a schematic view of an atomic layer deposition apparatus according to an exemplary embodiment of the invention. As shown in fig. 4, the atomic layer deposition apparatus includes a reaction chamber 1, a tail gas treatment device 10, two transmission lines, two corresponding purging branches, two tail gas treatment lines, and two precursor source bottles.

Specifically, the two transmission lines are respectively a transmission line 41 and a transmission line 42, the two purging branches are respectively a purging branch 45 and a purging branch 46, the two tail gas treatment lines are respectively a tail gas treatment line 47 and a tail gas treatment line 48, and the two precursor source bottles are respectively a precursor source bottle 5 and a precursor source bottle 6.

One end of the transfer lines 41, 42 is an inlet for inert gas, and the other end is connected to the reaction chamber 1. The same inert gas, which may be nitrogen, argon, etc., is supplied to the transfer line 41 and the transfer line 42.

The precursor source bottles 5 and 6 are respectively connected to the

transfer lines

41 and 42, and the

transfer lines

41 and 42 are respectively connected to the reaction chamber 1, so as to selectively introduce the corresponding precursors into the reaction chamber 1.

One end of the tail

gas treatment pipelines

47 and 48 is an inert gas inlet, the other end of the tail

gas treatment pipelines

47 and 48 is connected to the tail gas treatment device 10, and the tail

gas treatment pipelines

47 and 48 are respectively connected with the

transmission pipelines

41 and 42 through the purging

branches

45 and 46. The exhaust

gas treatment lines

47, 48 are optionally in communication with the exhaust gas treatment device 10 or the

corresponding transfer lines

41, 42.

The exhaust gas treatment line 47 is selectively communicated with the exhaust gas treatment device 10 or the transmission line 41 through a first valve assembly 53; the exhaust treatment line 48 is in selective communication with the exhaust treatment device 10 or the transfer line 42 via a first valve assembly 54.

The first valve assembly 53 comprises a first control valve 37 and a second control valve 39, wherein the first control valve 37 is arranged on the purge branch 45, and the second control valve 39 is arranged on the exhaust gas treatment line 47 and is located between the inlet side of the first control valve 37 and the exhaust gas treatment device 10; the first valve assembly 54 includes a first control valve 38 and a second control valve 40, wherein the first control valve 38 is disposed on the purge branch 46 and the second control valve 40 is disposed on the exhaust treatment line 48 between an inlet side of the first control valve 38 and the exhaust treatment device 10.

The delivery line 41 selectively passes the corresponding precursor into the reaction chamber 1 through the second valve assembly 51; the delivery line 42 selectively passes the corresponding precursor into the reaction chamber 1 through the second valve assembly 52.

The second valve assembly 51 comprises a third control valve 33, a fourth control valve 31 and a fifth control valve 32, wherein the third control valve 33 is arranged on the transfer line 41, the fourth control valve 31 is arranged on the connection line between the inlet of the third control valve 33 and the precursor source bottle 5, and the fifth control valve 32 is arranged on the connection line between the outlet of the third control valve 33 and the precursor source bottle 5. The second valve assembly 52 comprises a third control valve 36, a fourth control valve 34 and a fifth control valve 35, wherein the third control valve 36 is arranged on the transfer line 42, the fourth control valve 34 is arranged on the connection line between the inlet of the third control valve 36 and the precursor source bottle 6, and the fifth control valve 35 is arranged on the connection line between the outlet of the third control valve 36 and the precursor source bottle 6.

A first mass flow controller 21 is arranged at the inlet of the transmission pipeline 41, and a second mass flow controller 23 is arranged at the inlet of the tail gas treatment pipeline 47; a first mass flow controller 22 is provided at the inlet of the transfer line 42 and a second mass flow controller 24 is provided at the inlet of the tail gas treatment line 48.

The atomic layer deposition apparatus further comprises a vacuum pump 8, the vacuum pump 8 being connected to the reaction chamber 1 via a control valve 7. The upper part of the reaction chamber 1 is provided with a spray header 2, the lower part is provided with a base 3 and a substrate 4, and the substrate 4 is arranged on the base 3. Wherein, the control valve 7 is preferably a butterfly valve, and further, the valve core of the butterfly valve is preferably in a constant angle mode, that is, the valve core is kept at a fixed angle when the butterfly valve is opened, so that the frequent action of the butterfly valve is avoided to generate mechanical particles.

It will be appreciated by those skilled in the art that the atomic layer deposition apparatus may also comprise other lines of transfer lines, purge branches, off-gas treatment lines and corresponding precursors, and that how this may be arranged is known based on the above disclosure.

The process of entering the thin film deposition of the atomic layer deposition equipment according to the invention is shown in FIG. 5 and comprises the following steps:

firstly, a first precursor enters a reaction chamber:

the inert gas 11 with a certain flow rate, which enters from the transmission pipeline 41 and is controlled by the first mass flow controller 21, carries the first precursor in the precursor source bottle 5 into the reaction chamber 1, and performs adsorption or reaction on the substrate 4; the

inert gases

13 and 14 with larger flow rate which are controlled by the second

mass flow controllers

23 and 24 and enter from the tail

gas treatment pipelines

47 and 48 are discharged into the tail gas treatment device 10; a certain flow of inert gas 12, which enters from the transfer line 42 via the control of the first mass flow controller 22, enters directly into the reaction chamber 1.

In this step, the first control valve 37 corresponding to the delivery line 41 is closed, the second control valve 39 is opened, the third control valve 33 is closed, and the fourth control valve 31 and the fifth control valve 32 are opened; the first control valve 38 corresponding to the transfer line 42 is closed, the second control valve 40 is opened, the third control valve 36 is opened, and the fourth control valve 34 and the fifth control valve 35 are closed.

Large-flow gas purging pipeline and chamber:

the

inert gases

11, 12 of a certain flow rate controlled by the first

mass flow controllers

21, 22 entering from the transfer lines 41, 42 join the

inert gases

13, 14 of a larger flow rate controlled by the second

mass flow controllers

23, 24 entering from the

corresponding purge branches

45, 46, and enter the reaction chamber 1 together for a purge.

In this step, the

first control valves

37, 38 are opened, the

second control valves

39, 40 are closed, the third control valves 33, 36 are opened, the

fourth control valves

31, 34 and the

fifth control valves

32, 35 are closed.

③ purging pipelines and chambers with small flow gas:

the

inert gases

11 and 12 with certain flow rate controlled by the first

mass flow controllers

21 and 22 and entering from the

transmission pipelines

41 and 42 directly enter the reaction chamber 1to enter the secondary purging, and the

inert gases

13 and 14 with larger flow rate controlled by the second

mass flow controllers

23 and 24 and entering from the tail

gas treatment pipelines

47 and 48 are discharged into the tail gas treatment device 10.

In this step, the

first control valves

37, 38 are closed, the

second control valves

39, 40 are opened, the third control valves 33, 36 are opened, the

fourth control valves

31, 34 and the

fifth control valves

32, 35 are closed.

And fourthly, the second precursor enters a reaction chamber:

a certain flow of inert gas 12 entering from the transfer line 42 and controlled by the first mass flow controller 22 carries the second precursor in the precursor source bottle 6 into the reaction chamber 1to be adsorbed or reacted on the substrate 4; the

inert gases

13 and 14 with larger flow rate which are controlled by the second

mass flow controllers

23 and 24 and enter from the tail

gas treatment pipelines

47 and 48 are discharged into the tail gas treatment device 10; the inert gas 11 of a certain flow rate which is fed from the transfer line 41 and controlled by the first mass flow controller 21 is directly fed into the reaction chamber 1.

In this step, the first control valve 38 corresponding to the delivery line 42 is closed, the second control valve 40 is opened, the third control valve 36 is closed, and the fourth control valve 34 and the fifth control valve 35 are opened; the first control valve 37 corresponding to the transfer line 41 is closed, the second control valve 39 is opened, the third control valve 33 is opened, and the fourth control valve 31 and the fifth control valve 32 are closed.

Large-flow gas purging pipeline and chamber:

the fifth step is the same as the second step.

Sixthly, purging the pipeline and the cavity by small-flow gas:

step sixthly, the same as the step III.

In the process operation, the step (c) and the step (v) can be repeated for a plurality of times.

And (6) judging whether the repetition times of the steps (I) to (II) reach the set cycle times, if so, finishing the process, otherwise, returning to the step (I).

In the film deposition process, the control valve 7 adopts a butterfly valve working in a constant angle mode, namely, a valve core is kept at a fixed angle when the butterfly valve is opened, and mechanical particles generated by frequent actions of the butterfly valve are avoided. The fixed angle is obtained by combining process pressure and total flow of introduced precursor, and specifically can be determined by the following method: the total air inlet flow in the process is calculated, after the air is introduced into the reaction chamber 1, the opening angle of the butterfly valve is manually adjusted to change the air inlet flow from large to small, the pressure change of the reaction chamber 1 is observed, and after the required pressure is reached, the angle can be used as a fixed angle in the process in the case of 1 torr.

In the above case that the atomic layer deposition apparatus includes two transmission pipelines, a tail gas treatment pipeline, and a purging branch pipeline, those skilled in the art can understand that the atomic layer deposition apparatus may further include a multi-transmission pipeline, a tail gas treatment pipeline, and a purging branch pipeline. When the atomic layer deposition equipment comprises a plurality of pipelines, different pipelines can be selected to operate based on a similar method, so that the inert gas carries different precursors into the reaction chamber to perform adsorption or reaction.

FIG. 6 is a graph illustrating the pressure of a process chamber as a function of time during an atomic layer deposition process according to the present invention. As can be seen from the figure, the first and the fourth are the stages of introducing the precursor into the chamber, and the pressure of the chamber is the process pressure; the second, third, fifth and sixth are purging pipeline and chamber stages, wherein the second and fifth are large flow purging stages with pressure gradient process, the third and sixth are small flow purging stages with chamber pressure process pressure, also called pressure stabilizing stage. The purging stage can also be divided into two stages II and III, namely II is a large-flow gas and carrier gas converging purging pipeline and a chamber, the pressure of the chamber is gradually increased to the peak pressure, the pressure does not need to be increased to the peak pressure, a gradual change airflow field is formed, and the purging effect can be determined visually; III, introducing the large-flow gas into a tail gas treatment device, and gradually reducing the pressure of the chamber from the peak pressure to the process pressure and stabilizing for a certain time. Through the purging process, a gradual change airflow field is formed in the pipeline and the cavity, so that residual precursors or particles can be purged completely, process particles are prevented from being generated, and the quality of the film is improved.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen in order to best explain the principles of the embodiments, the practical application, or improvements made to the technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. An atomic layer deposition device is characterized by comprising a reaction chamber, a tail gas treatment device, a plurality of transmission pipelines, a plurality of tail gas treatment pipelines, a plurality of purging branch pipelines and a plurality of precursor source bottles, wherein,

each precursor source bottle is correspondingly connected into one transmission pipeline, each transmission pipeline is connected to the reaction chamber, and the corresponding precursor is selectively introduced into the reaction chamber through inert gas introduced into the transmission pipeline;

each tail gas treatment pipeline is connected to the tail gas treatment device, and each tail gas treatment pipeline is connected with one transmission pipeline through the corresponding purging branch so as to introduce inert gas with a large flow into the transmission pipeline;

each tail gas treatment pipeline is selectively communicated with the tail gas treatment device or the corresponding transmission pipeline and is used for forming a gradual change airflow field in the transmission pipeline and the reaction chamber.

2. The atomic layer deposition apparatus according to claim 1, wherein each of the exhaust treatment lines is selectively in communication with the exhaust treatment device or the transfer line via a first valve assembly;

the first valve assembly includes:

the first control valve is arranged on the purging branch;

3. The atomic layer deposition apparatus according to claim 1, wherein each of the delivery lines selectively passes the corresponding precursor into the reaction chamber through a second valve assembly;

the second valve assembly includes:

a third control valve provided on the transfer line;

4. The atomic layer deposition apparatus according to claim 1, wherein a first mass flow controller is provided at an inlet of each of the transport lines and a second mass flow controller is provided at an inlet of each of the off-gas treatment lines.

5. The atomic layer deposition apparatus according to claim 1, further comprising a vacuum pump connected to the reaction chamber via a butterfly valve having a spool in a constant angle mode.

6. An atomic layer deposition method for atomic layer deposition using the atomic layer deposition apparatus according to any of claims 1to 5, comprising the steps of:

step 2, the inert gas entering from each transmission pipeline is converged with the inert gas with larger flow entering from the corresponding purging branch into the transmission pipeline, and enters the reaction chamber together for primary purging;

step 4, repeating the steps 1to 3 for a plurality of times;

step 5, judging whether the repetition times in the step 4 reach the set cycle times, if so, ending the process, otherwise, returning to the step 1;

wherein, the gradual change gas flow field is formed in the transmission pipeline and the reaction chamber through the steps 2 and 3.

7. The atomic layer deposition method according to claim 6,

in the step 1, a third control valve on one of the transmission pipelines is closed, fourth and fifth control valves are opened, third control valves on the other transmission pipelines are opened, a second control valve on each tail gas treatment pipeline is opened, and all the other control valves are closed;

in the step 2, the third control valve on each transmission pipeline is opened, the first control valve on each purging branch is opened, and all the other control valves are closed;

in the step 3, the third control valve on each transmission pipeline is opened, the second control valve on each tail gas treatment pipeline is opened, and all the other control valves are closed.

8. The atomic layer deposition method according to claim 6, wherein the butterfly valve operates in a constant angle mode.

9. The atomic layer deposition method according to claim 8, characterized in that, before step 4, the following steps are performed:

and 3.1, repeatedly executing the step 2 and the step 3 for multiple times.

10. The atomic layer deposition method according to claim 9, wherein in step 4, an inert gas is used to carry a different precursor into the reaction chamber each time steps 1to 3 are performed.