JP2022500561A - Gas intake system, atomic layer deposition equipment and methods - Google Patents

Abstract

This disclosure is for a gas intake system comprising a gas intake pipeline configured to introduce a reaction precursor into the reaction chamber (8) through a gas distribution device (7) and equipped with a gas intake on / off valve. There; further disclosed a gas intake system including an exhaust pipeline (4) that communicates with both the gas distribution device (7) and the reaction chamber (8) and is equipped with an exhaust on / off valve (10). is doing. Further, this disclosure discloses an atomic layer deposition apparatus and an atomic layer deposition method.

Description

This disclosure relates to the field of semiconductor manufacturing technology, in particular gas intake systems, atomic layer deposition equipment, and atomic layer deposition methods.

Atomic layer deposition (ALD) refers to the method of plating a substance on the surface of a substrate in the form of a layer-by-layer monoatomic film, where the monoatomic film has a cyclical growth process and each preparation cycle is generally. Includes two self-restrictive reactions. By introducing the first reaction precursor into the reaction chamber at a specific temperature, the molecules of the first reaction precursor are adsorbed as an activator on the surface of the substrate (mainly through chemisorption). .. When the adsorption of the first reaction precursor reaches saturation, the chemical adsorption is completed and the reaction between the first reaction precursor and the surface of the substrate is self-limiting control (first self-limiting reaction). Is realized. After the first self-restricting reaction is complete, the first reaction precursor (generally, along with the by-products of the reaction between the first reaction precursor and the surface of the substrate) has a particular parsing method. It is purged from the reaction chamber using and then a second reaction precursor is introduced; this second reaction precursor reacts with the activator (first reaction precursor) and is adsorbed on the surface of the substrate. It forms a single layer of film to be prepared on the surface of the substrate and releases gaseous by-products.

_{Taking SiH 4} and WF ₆ as examples of the two reaction precursors, as shown in FIG. 1, the gas intake system is configured to introduce _{SiH 4} and WF ₆ into the reaction chamber through the shower head, respectively. Includes two gas intake pipelines (A, B), each of which has a mass flow controller (MFC) configured to control the gas flow. I have. In addition, each of the two gas intake pipelines (A, B) should be connected or disconnected from the gas intake pipeline so that alternate introduction of the two reaction precursors into the reaction chamber is achieved. It is equipped with a high-speed switching valve (hereinafter referred to as an ALD valve) configured to realize this. In addition, the gas intake system has two exhaust pipelines (C), each connecting the gas intake pipelines (A, B) to the foreline of the reaction chamber and communicating the gas intake pipeline with the foreline. , D), the foreline is configured to expel residual gas or by-products, and each of the two exhaust pipelines (C, D) has two reaction precursors into the reaction chamber. It is equipped with an ALD valve that discharges the reaction precursor that was not introduced into the reaction chamber through the foreline while being introduced alternately.

Using the gas intake system described above, the ALD valves are alternately opened and closed to allow rapid and alternating introduction of the two reaction precursors into the reaction chamber, completing the preparation of the ALD thin film. However, the above gas intake system inevitably has the following problems in practical applications.

First, closing the ALD valve can prevent reaction precursors from entering the reaction chamber, but causes an increase in pressure in the gas intake pipeline in which the ALD valve is installed. Therefore, when the ALD valve is reopened, the reaction precursor will enter and flow into the reaction chamber with extremely unstable pressure, making it difficult for the MFC to control its gas flow.

Second, over a period of time, reaction precursors are also introduced into the foreline, reducing the total amount of gas entering the reaction chamber and resulting in unstable process pressure inside the chamber. , It becomes difficult to accurately stabilize and control the total gas flow rate and the process pressure inside the chamber; in addition, the flow rate fluctuation in the gas intake pipeline affects the pressure fluctuation inside the chamber. It is sufficient to increase the particles in the chamber, thereby affecting the outcome of the process, especially the uniformity of the membrane.

In view of the above, embodiments of this disclosure provide gas intake systems and control methods that apply to the ALD process.

According to one aspect of an embodiment of this disclosure, it is configured to communicate with a gas distribution device and introduce a reaction precursor into the reaction chamber through the gas distribution device, and is provided with a gas intake on / off valve. A gas intake system including a gas intake pipeline is provided; and the gas intake system is further provided.
An exhaust pipeline that communicates with both the gas distribution device and the reaction chamber and is equipped with an exhaust on / off valve.
including.

Optionally, the gas intake pipeline comprises at least two gas intake pipelines configured to introduce different reaction precursors into the reaction chamber through the gas distribution device, said at least two gas intake pipelines. Each of the above is provided with the gas intake on / off valve.

Optionally, a buffer device capable of storing a predetermined volume of reaction precursor is located on the gas intake pipeline and upstream of the gas intake on / off valve.

Optionally, the buffer device is
A tubular cavity with an inner diameter greater than the inner diameter of the gas intake pipeline,
including.

Optionally, the gas intake pipeline is further equipped with a mass flow controller.

In the option, the gas intake on / off valve is a solenoid valve.

In the option, the exhaust on / off valve is a solenoid valve.

Optionally, the gas intake pipeline includes two gas intake pipelines configured to introduce _{SiH 4} and WF ₆ into the reaction chamber through the gas distribution device.

According to another aspect of this disclosure, an ALD method is provided in which the deposition process is carried out by utilizing the ALD apparatus provided by this disclosure.
At the deposition stage, opening the gas intake on / off valve and simultaneously closing the exhaust on / off valve so that the reaction precursor is introduced into the reaction chamber through the gas distribution device.
In the purging step, the gas intake is such that the reaction precursor left in the gas distribution device is discharged into the reaction chamber and then the reaction precursor is discharged from the reaction chamber through the foreline. Closing the on / off valve and opening the exhaust on / off valve at the same time
including.

Optionally, the gas intake pipeline includes two gas intake pipelines, each of which introduces a first reaction precursor into the reaction chamber through the gas distribution device. A first gas intake pipeline configured to introduce a second gas intake pipeline and a second gas intake pipeline configured to introduce a second reaction pioneer; and the gas intake on / off valve is the two gases. The two gas intake on / off valves, including the intake on / off valve, are the first gas intake on / off valve located on the first gas intake pipeline and the first gas intake on / off valve, respectively. A second gas intake on / off valve located on the second gas intake pipeline.
The ALD method is
In the first deposition stage, the first gas intake on / off valve is opened so that the first reaction precursor is introduced into the reaction chamber through the gas distribution device, and at the same time the second. With closing the gas intake on / off valve and the exhaust on / off valve;
In the first purging step, the first reaction precursor remaining in the gas distribution device is discharged into the reaction chamber, after which the first reaction precursor is discharged through the foreline into the reaction chamber. Closing the first gas intake on / off valve and simultaneously opening the exhaust on / off valve so that it is exhausted from.
In the second deposition stage, the second gas intake on / off valve is opened so that the second reaction precursor is introduced into the reaction chamber through the gas distribution device, and at the same time the first. With closing the gas intake on / off valve and the exhaust on / off valve;
In the second purging step, the second reaction precursor remaining in the gas distribution device is discharged into the reaction chamber, after which the second reaction precursor is discharged through the foreline into the reaction chamber. Closing the second gas intake on / off valve and opening the exhaust on / off valve at the same time so that it is discharged from the;
Performing the cycle consisting of the first deposition step, the first purge step, the second deposition step, and the second purge step at least once.
including.

In the technical solution of the gas intake system, the ALD apparatus and ALD method of the present disclosure provide an exhaust pipeline that communicates with the gas distribution device and the reaction chamber so that the reaction precursors left in the gas distribution device can be removed. It is possible to flow into the reaction chamber when the gas intake on / off valve on the gas intake pipeline is closed, and then drain through the foreline of the reaction chamber, but in the foreline. In light of the prior art of direct discharge of the reaction precursor into the gas intake pipeline, this can avoid an increase in pressure in the gas intake pipeline and ensure that the total amount of gas entering the reaction chamber remains unchanged. As a result, it is possible to improve the stability of the process pressure inside the chamber, and it is possible to facilitate the control of the total gas flow rate and the process pressure inside the chamber, thereby the fact. In addition, the particles produced due to pressure fluctuations or flow rate fluctuations during the process are reduced, improving membrane uniformity and membrane yield.

Additional aspects and benefits of embodiments of this disclosure will be apparent from those descriptions described below or will be learned from the practical application of this disclosure.

In order to more clearly illustrate the technical solution in the embodiments of this disclosure, or that in the prior art, the drawings used in the description of the embodiments or prior art are briefly introduced below. It is clear that the drawings described below are used only for illustration of some embodiments of this disclosure, and one of ordinary skill in the art, without any creative work. It is possible to draw other drawings from the following drawings.

It is a schematic structural diagram of the gas intake system used in the prior art. It is a schematic structural diagram of the gas intake system according to this disclosure. It is a flowchart of the ALD process performed by utilizing the gas intake system provided by this disclosure.

Hereinafter, the disclosure will be described more fully with reference to the drawings, illustrating exemplary embodiments of the disclosure. In the following, with reference to the drawings, the technical solutions in the embodiments of this disclosure will be described clearly and completely. It is clear that the embodiments described herein are not all of the embodiments of this disclosure, but rather only some of them. Based on the embodiments described in this disclosure, all other embodiments drawn by one of ordinary skill in the art without creative work are within the protection of this disclosure. The technical solution of this disclosure will be described from multiple aspects with reference to the drawings and embodiments.

For convenience of explanation, the terms "left", "right", "top", and "bottom" used hereafter are consistent with the left, right, top, and bottom in the drawing. The terms "first", "second", and these kinds of terms used hereafter are merely for the purpose of distinguishing between the elements in the description and have no other special meaning. Not.

As shown in FIG. 2, this disclosure provides a gas intake system configured to provide process gas for the reaction chamber 8 and applicable to the ALD process. Specifically, the gas intake system includes a gas intake pipeline configured to communicate with the gas distribution device 7 and to introduce the reaction precursor into the reaction chamber 8 through the gas distribution device 7. The pipeline comprises a gas intake on / off valve configured to connect or disconnect the gas intake pipeline. The gas distribution device 7 is configured to distribute the gas and allows the gas to flow uniformly into the reaction chamber 8. For the ALD process, the gas distribution device 7 has the ability to separate at least two reaction precursors from each other. Specifically, the gas distribution device 7 can include at least two independent gas intake channels and a scattering chamber, with at least two gas intake channels in a one-to-one correspondence and at least two gas intake pipes. It is configured to communicate with the line and uniformly deliver the reaction precursor material from the gas intake pipeline into the reaction chamber 8.

In this embodiment, as shown in FIG. 2, two gas intake pipelines, namely the first gas intake pipeline 1 and the second gas intake pipeline 2, react with two different reaction precursors. It is arranged to be introduced into the chamber 8 through the gas distribution device 7, for example, the first gas intake pipeline 1 _{to deliver SiH 4} and the second gas intake pipeline 2 to deliver _{WF 6.} Each is configured. In addition, the first gas intake pipeline 1 is provided with a first gas intake on / off valve 3; the second gas intake pipeline 2 is provided with a second gas intake on / off valve 3. A valve 5 is provided. By alternately opening the first gas intake on / off valve 3 and the second gas intake on / off valve 5, it is possible to alternately introduce the two reaction precursors into the reaction chamber 8. .. Preferably, both the first gas intake on / off valve 3 and the second gas intake on / off valve 5 are high-speed switching valves such as solenoid valves. In this method, the two reaction precursors can enter the reaction chamber alternately and quickly to complete the preparation of the ALD thin film.

Optionally, the gas intake pipeline is equipped with a mass flow controller (MFC) configured to control the gas flow within the gas intake pipeline.

The gas intake system further includes an exhaust pipeline 4 that communicates with both the gas distribution device 7 and the reaction chamber 8. Specifically, the exhaust pipeline 4 is configured to communicate the scattering chamber of the gas distribution device 7 with the reaction chamber 8. The exhaust pipeline 4 includes an exhaust on / off valve 10 configured to connect or disconnect the exhaust pipeline 4.

The residual reaction precursor in the gas distribution device 7 can flow into the reaction chamber 8 through the exhaust pipeline 4 when the gas intake on / off valve on the gas intake pipeline is closed. After that, it is discharged through the foreline 9 of the reaction chamber 8, which reacts from the gas intake pipeline into the foreline in light of the prior art in which the reaction precursor is directly discharged into the foreline 9. It is possible to avoid the diversion caused by the direct entry of the precursor, thereby avoiding the increase in pressure in the gas intake pipeline. On the other hand, it can be guaranteed that the total amount of gas entering the reaction chamber 8 does not change, and as a result, the stability of the process pressure inside the reaction chamber 8 can be improved, and the total flow rate of gas and the chamber It is possible to facilitate control of the inner process pressure, which effectively reduces the particles produced due to pressure or flow rate fluctuations between processes and film uniformity. And the yield of the membrane is improved.

In the option, the exhaust on / off valve 10 is a high speed switching valve such as a solenoid valve, and as a result, it becomes possible to realize high speed switching between the exhaust pipeline and the intake pipeline.

Taking as an example a gas intake system that delivers the _{two reaction precursors SiH 4} and WF ₆ shown in FIG. 2, as shown in FIG. 3, this ALD process is:
The first gas intake on / off valve 3 is opened and at the same time the second gas intake on so that the first reaction precursor (SiH _{4) is introduced into the reaction chamber 8 through the gas distribution device 7.} With the first deposition stage in which the off valve 5 and the exhaust on / off valve 10 are closed;
A first gas intake on / off valve so that the first reaction precursor remaining in the gas distribution device 7 is discharged into the reaction chamber 8 and then discharged from the reaction chamber 8 through the foreline 9. With the first purge stage where 3 is closed and the exhaust on / off valve 10 is opened at the same time;
The second gas intake on / off valve 5 is opened and at the same time the first gas intake on / off so that the second reaction precursor (WF _{6) is introduced into the reaction chamber through the gas distribution device 7.} With the second deposition stage in which the off valve 3 and the exhaust on / off valve 10 are closed;
A second gas intake on / off valve so that the second reaction precursor remaining in the gas distribution device 7 is discharged into the reaction chamber 8 and then discharged from the reaction chamber 8 through the foreline 9. A second purge step in which 5 is closed and the exhaust on / off valve 10 is opened at the same time.
including.

A cycle consisting of these first deposition step, first purge step, second deposition step, and second purge step is performed at least once to complete the ALD process.

Optionally, a buffer device capable of storing a predetermined volume of reaction precursor is placed on the gas intake pipeline upstream of the gas intake on / off valve. In this embodiment, as shown in FIG. 2, the first gas intake pipeline 1 has a first buffer device 11 and the second gas intake pipeline 2 has a second buffer device 12. However, each is prepared. In the gas intake pipeline when the gas intake on / off valve is reopened by storing a specific volume of reaction precursor in the buffer device when the gas intake on / off valve is closed. It is possible to avoid large flow rate fluctuations and large pressure fluctuations in. Since the different gas intake on / off valves are switched to each other at very short intervals, the buffer device can effectively stabilize the pressure and flow rate of the reaction precursor, with respect to the control of the MFC. It has no effect.

Optionally, the buffer device includes a tubular cavity with an inner diameter greater than the inner diameter of the gas intake pipeline. Indeed, in practical applications, buffer devices are implemented as other structures or in other embodiments as long as it is possible to effectively stabilize the pressure and flow rate of the reaction precursor. Sometimes.

As another technical solution, this disclosure further provides an ALD device. As shown in FIG. 2, the ALD apparatus includes a reaction chamber 8, a gas distribution device 7 located at the top of the reaction chamber 8, a gas intake system as described above, and a foreline 9. ..

By utilizing the gas intake system described above, the ALD apparatus provided by this disclosure improves the stability of the process pressure inside the chamber and facilitates the control of the total gas flow rate and the process pressure inside the chamber. It is possible, which effectively reduces the particles produced due to pressure fluctuations or flow rate fluctuations between processes, improving membrane uniformity and membrane yield.

As yet another technical solution, the disclosure further provides an ALD method in which the deposition process is performed by utilizing the ALD apparatus provided by this disclosure described above. This ALD method is:
At the deposition stage, opening the gas intake on / off valve and simultaneously closing the exhaust on / off valve so that the reaction precursor is introduced into the reaction chamber through the gas distribution device;
During the purging phase, the gas intake on / off valve is closed and simultaneously exhausted so that the reaction precursors left in the gas distribution device are discharged into the reaction chamber and then discharged from the reaction chamber through the foreline. Opening the on / off valve and
including.

By performing the deposition process utilizing the ALD apparatus described above, the ALD method provided by this disclosure improves the stability of the process pressure inside the reaction chamber, as well as the total gas flow rate and inside the reaction chamber. It is possible to facilitate the control of process pressure, which effectively reduces the particles produced due to pressure fluctuations or flow rate fluctuations between processes, membrane uniformity and membrane. Yield is improved.

Specifically, taking the gas intake system utilized by the ALD apparatus shown in FIG. 2 as an example, two gas intake pipelines, namely the first gas intake pipeline 1 and the second gas intake. The pipeline 2 is arranged to introduce the first reaction precursor and the second reaction precursor into the reaction chamber 8 through the gas distribution device 7; and two gas intake on / off valves, ie. A first gas intake on / off valve 3 and a second gas intake on / off valve 5 are arranged on the first gas intake pipeline 1 and the second gas intake pipeline 2, respectively. ..

This ALD method is:
In the first deposition stage, the first gas intake on / off valve 3 is opened and simultaneously so that the first _{reaction precursor (SiH 4) is introduced into the reaction chamber 8 through the gas distribution device 7.} Closing the second gas intake on / off valve 5 and exhaust on / off valve 10;
In the first purging step, the first reaction precursor remaining in the gas distribution device 7 is discharged into the reaction chamber 8 and then discharged from the reaction chamber 8 through the foreline 9. Closing the gas intake on / off valve 3 and opening the exhaust on / off valve 10 at the same time;
In the second deposition stage, the second gas intake on / off valve 5 is opened and simultaneously the second so that _{the second reaction precursor (WF 6) is introduced into the reaction chamber through the gas distribution device 7.} Closing the gas intake on / off valve 3 and the exhaust on / off valve 10 of 1;
In the second purging step, the second reaction precursor remaining in the gas distribution device 7 is discharged into the reaction chamber 8 and then discharged from the reaction chamber 8 through the foreline 9. Closing the gas intake on / off valve 5 and opening the exhaust on / off valve 10 at the same time;
A cycle consisting of a first deposition step, a first purge step, a second deposition step, and a second purge step is performed at least once to complete the ALD process.
including.

In summary, in the technical solution of the gas intake system, the ALD apparatus and ALD method of this disclosure are the reactions left in the gas distribution device by providing an exhaust pipeline that communicates with the gas distribution device and reaction chamber. Pioneer material can flow into the reaction chamber when the gas intake on / off valve on the gas intake pipeline is closed, and is then discharged through the foreline of the reaction chamber. However, in light of the prior art in which the reaction precursor is discharged directly into the foreline, this avoids an increase in pressure in the gas intake pipeline and does not change the total amount of gas entering the reaction chamber. As a result, it is possible to improve the stability of the process pressure inside the chamber, and it is possible to facilitate the control of the total gas flow rate and the process pressure inside the chamber. This effectively reduces the particles produced due to pressure or flow rate fluctuations between processes, improving membrane uniformity and membrane yield.

Unless otherwise stated, where any of the technical solutions in this disclosure above disclose a numerical range, the disclosed numerical range is the preferred numerical range. Those skilled in the art will appreciate that the preferred numerical range merely covers values that lead to obvious technical effects, or representative values among many implementable values. And. Since there are many implementable values and it is not possible to list all of them, some of those values are disclosed here in the illustration of the technical solution in this disclosure. As such, the values listed above should not be considered to limit the scope of protection of this disclosure.

On the other hand, unless otherwise stated, this disclosure discloses or, where it is related, a component or structural member that is fixedly connected to each other, the fixed connection is removably fixed. It can be interpreted as a connection (such as through bolts or screws) or a non-removably fixed connection (such as by riveting or welding). Alternatively, the fixed connections to each other can be replaced by an integral structure (eg, integrally formed by the casting process) (unless it is clear that the integral formation process is not feasible).

In addition, unless otherwise stated, the terms used to indicate a particular positional relationship or shape in any of the technical solutions of this disclosure above are similar, similar, or similar. It also shows an approximate state or shape. Any of the parts provided by this disclosure may be assembled by multiple independent components or may be independent parts manufactured by an integral formation process.

The above embodiments are intended only to illustrate the technical solutions of this disclosure and do not limit those technical solutions. Although this disclosure has been described in detail with reference to preferred embodiments, those skilled in the art will be able to modify certain embodiments of this disclosure or create equivalent substitutes for parts of technical feature. Need to be understood that is possible. Those modifications and equivalent substitutions made without deviation from the spirit of the technical solution of this disclosure shall be deemed to fall within the scope of protection of the technical solution of this disclosure.

The description of this disclosure is given for purposes of illustration and is not intended to be exhaustive or to limit this disclosure. Many modifications and variations are apparent to those skilled in the art in this area. Embodiments better illustrate the principles and practical applications of this disclosure, and those skilled in the art will understand this disclosure to provide embodiments for a variety of specific purposes, including various modifications. Selected and described to be able to be designed.

1 1st gas intake pipeline 2 2nd gas intake pipeline 3 1st gas intake on / off valve 4 Exhaust pipeline 5 2nd gas intake on / off valve 7 Gas distribution device 8 Reaction chamber 9 Foreline 10 Exhaust on / off valve 11 First buffer device 12 Second buffer device

Claims (11)

A gas intake system that includes a gas intake pipeline that communicates with a gas distribution device, is configured to introduce a reaction precursor into the reaction chamber through the gas distribution device, and is equipped with a gas intake on / off valve. hand,
An exhaust pipeline that communicates with both the gas distribution device and the reaction chamber and is equipped with an exhaust on / off valve.
Including gas intake system. The gas intake pipeline includes at least two gas intake pipelines configured to introduce different reaction precursors into the reaction chamber through the gas distribution device, and into each of the at least two gas intake pipelines. 1 is the gas intake system according to claim 1, wherein the gas intake on / off valve is provided. Claim 1 or 2 a buffer device capable of storing a predetermined volume of reaction precursor is located on the gas intake pipeline and upstream of the gas intake on / off valve. The gas intake system described in. The buffer device is
A tubular cavity with an inner diameter greater than the inner diameter of the gas intake pipeline,
3. The gas intake system according to claim 3. The gas intake system according to claim 1 or 2, further comprising a mass flow controller in the gas intake pipeline. The gas intake system according to claim 1 or 2, wherein the gas intake on / off valve is an electromagnetic valve. The gas intake system according to claim 1, wherein the exhaust on / off valve is a solenoid valve. The gas intake system according to claim 2, wherein the gas intake pipeline includes two gas intake pipelines configured to introduce _{SiH 4} and WF ₆ into the reaction chamber through the gas distribution device. A reaction chamber, a gas distribution device located at the top of the reaction chamber, a gas intake system, and a foreline, wherein the gas intake system is described in any one of claims 1-8. The atomic layer depositor, which is the gas intake system of the above. A atomic layer deposition method for carrying out an atomic layer deposition process by using the atomic layer deposition apparatus according to claim 9.
At the deposition stage, the gas intake on / off valve is opened and at the same time the exhaust on / off valve is closed so that the reaction precursor is introduced into the reaction chamber through the gas distribution device.
In the purging step, the gas intake is such that the reaction precursor left in the gas distribution device is discharged into the reaction chamber and then the reaction precursor is discharged from the reaction chamber through the foreline. Closing the on / off valve and opening the exhaust on / off valve at the same time
Atomic layer deposition method, including. The gas intake pipeline includes two gas intake pipelines, each of which is configured to introduce a first reaction precursor into the reaction chamber through the gas distribution device. A second gas intake pipeline configured to introduce a first gas intake pipeline and a second reaction precursor; and the gas intake on / off valve is two gas intake on / off valves. Including the off valve, the two gas intake on / off valves are a first gas intake on / off valve located on the first gas intake pipeline and a second gas intake on / off valve, respectively. A second gas intake on / off valve located on the gas intake pipeline.
The atomic layer deposition method is:
In the first deposition stage, the first gas intake on / off valve is opened so that the first reaction precursor is introduced into the reaction chamber through the gas distribution device, and at the same time the second. With closing the gas intake on / off valve and the exhaust on / off valve;
In the first purging step, the first reaction precursor remaining in the gas distribution device is discharged into the reaction chamber, after which the first reaction precursor is discharged through the foreline into the reaction chamber. Closing the first gas intake on / off valve and simultaneously opening the exhaust on / off valve so that it is exhausted from.
In the second deposition stage, the second gas intake on / off valve is opened so that the second reaction precursor is introduced into the reaction chamber through the gas distribution device, and at the same time the first. With closing the gas intake on / off valve and the exhaust on / off valve;
In the second purging step, the second reaction precursor remaining in the gas distribution device is discharged into the reaction chamber, after which the second reaction precursor is discharged through the foreline into the reaction chamber. Closing the second gas intake on / off valve and opening the exhaust on / off valve at the same time so that it is discharged from the;
Performing the cycle consisting of the first deposition step, the first purge step, the second deposition step, and the second purge step at least once.
10. The atomic layer deposition method according to claim 10.

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