KR20190063941A - Dry clean apparatus and method for removing polysilicon seletively - Google Patents

Abstract

The present invention relates to a dry cleaning apparatus and method for selectively removing polysilicon. The method according to the present invention comprises: a step of supplying a fluorine-containing gas in a plasma state and a hydrogen-containing gas in a non-plasma state to a substrate on which a silicon oxide, silicon nitride and polysilicon are formed, to change the surface of silicon oxide and silicon nitride into ammonium hexafluorosilicate, thereby forming a protective film; a step of stopping the supply of the hydrogen-containing gas and continuously supplying the fluorine-containing gas in the plasma state to selectively remove polysilicon by fluorine radicals; and finally, a protective film removal step of removing, through annealing, the protective film made of ammonium hexafluorosilicate. According to the present invention, the polysilicon can be selectively etched by changing the surface of silicon nitride and silicon oxide that are formed on a substrate, into an ammonium hexafluorosilicate ((NH_4)_2SiF_6) solid layer and using the ammonium hexafluorosilicate solid layer as a protective layer.

Description

[0001] DRY CLEAN APPARATUS AND METHOD FOR REMOVING POLYSILICON SELETIVELY [0002]

The present invention relates to a dry cleaning apparatus and method for selectively removing polysilicon. More specifically, the present invention relates to a method for producing a silicon nitride film by changing the surface of silicon nitride and silicon oxide formed on a substrate to an ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ) solid layer and using this ammonium hexafluorosilicate solid layer as a protective film To a dry cleaning apparatus and method capable of selectively etching polysilicon.

BACKGROUND ART As semiconductor device circuits become increasingly highly integrated and highly refined, etching and cleaning techniques that exhibit high selectivity characteristics between different types of patterns such as polysilicon, silicon oxide, silicon nitride, and the like are required.

On the other hand, wet etching and dry etching are techniques for etching polysilicon. The wet etching technique has an excellent ability to remove particles, but it has a problem that it is difficult to control the selection ratio for the micro-etching of the atomic level and the deterioration of the cleaning ability due to the surface tension in the high aspect ratio pattern. In the dry etching technique, a damage layer is generated after etching due to ion bombardment incident on the wafer. Further, there is a problem that a subsequent process for removing the damage layer is additionally required.

Recently, as an alternative technique to solve this problem, a hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ) solid layer is formed by a gas reaction or a radical reaction, and the solid layer thus produced is heated Dry cleaning techniques are being widely used to remove heterogeneous patterns depending on the reaction conditions, and can be selectively removed without damaging the substrate.

However, a technique for selectively etching polysilicon using such an ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ) solid layer is not known.

Korean Patent Laid-Open Publication No. 10-2009-0083857 (Published Date: August 04, 2009, titled: Method of removing polysilicon film and computer readable storage medium)

In the present invention, the surface of silicon nitride or silicon oxide formed on a substrate is changed to a solid layer of ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ), and the solid layer of ammonium hexafluorosilicate is used as a protective film to remove polysilicon And an object thereof is to provide a dry cleaning apparatus and method capable of selectively etching.

A dry cleaning method for selectively removing polysilicon to solve such a technical problem is a method of cleaning a substrate on which a silicon oxide, a silicon nitride, and a polysilicon are formed, the silicon oxide, and the silicon nitride A protective film is formed by supplying a fluorine-containing gas in a plasma state and a hydrogen-containing gas in a nonplasma state to change the surface of the silicon oxide and the nitride nitride to ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ) A polysilicon removing step of stopping supply of the hydrogen-containing gas and continuing supply of the fluorine-containing gas in the plasma state to selectively remove the polysilicon with fluorine radicals, and a step of removing the polysilicon by a heat treatment to form a protective film made of ammonium hexafluorosilicate To remove the protective film removing step The.

Wherein the RF power source for plasma-forming the fluorine-containing gas and the fluorine-containing gas is continuously supplied in the protective film forming step and the polysilicon removing step, And is supplied only at the protective film forming step.

In the dry cleaning method for selectively removing polysilicon, the time for supplying the hydrogen-containing gas is 1 to 10 seconds.

In the dry cleaning method for selectively removing polysilicon, the protective film forming step, the polysilicon removing step, and the protective film removing step are continuously performed in an in-situ cleaning method in the same chamber .

In the dry cleaning method for selectively removing polysilicon, the protective film removing step evaporates and removes the protective film made of ammonium hexafluorosilicate by supplying only an inert gas in a state in which the plasma is shut off.

Wherein the temperature of the chuck is controlled to 80 to 120 degrees and the heating temperature of the showerhead providing the path for supplying the fluorine-containing gas in the plasma state and the hydrogen-containing gas is 100 - 200 degrees, and the heating temperature of the inner wall surface of the chamber is 80 to 100 degrees.

A dry cleaning method for selectively removing polysilicon, characterized in that the hydrogen containing gas comprises H ₂ or NH ₃ or H ₂ O.

A dry cleaning apparatus for selectively removing polysilicon according to the present invention includes a chuck provided in a chamber and having a substrate on which silicon oxide, silicon nitride, and polysilicon are formed, a chuck heating unit for heating the chuck, An RF electrode having a first supply path provided with a path for supplying a fluorine-containing gas to which an RF power for plasma generation is applied, and a RF electrode connected to a ground terminal of the RF power source, A second supply path for supplying a plasma-treated fluorine-containing gas in the plasma generation region to the substrate, and a path for supplying a hydrogen-containing gas to the substrate, And a third supply path which is divided into a first supply path and a second supply path, Containing gas which reacts with the silicon oxide and the silicon nitride is supplied to the substrate through the third supply path and a hydrogen-containing gas in a non-plasma state is supplied to the substrate through the third supply path to supply the silicon oxide, by changing the silicic acid ammonium _{((NH 4) 2 SiF 6} ) the surface of the nitride nitride hexafluoro produce a protective film, and the polyester in the silicon removal process, the hydrogen containing stop the supply of the gas and the fluorine-containing gas in the plasma state And the polysilicon is selectively removed with a fluorine radical. In the process of removing the protective film, the protective film made of ammonium hexafluorosilicate is removed through heat treatment.

Wherein a RF power source for plasma-forming the fluorine-containing gas and the fluorine-containing gas is continuously supplied during the protective film forming process and the polysilicon removing process, And is supplied only in the process of forming the protective film.

In the dry scrubber for selectively removing polysilicon, the time for supplying the hydrogen-containing gas is 1 to 10 seconds.

In the dry cleaning apparatus for selectively removing polysilicon, the protective film forming process, the polysilicon removing process, and the protecting film removing process are continuously performed in an in-situ cleaning method in the same chamber .

The dry scrubber for selectively removing polysilicon is characterized in that, in the process of removing the protective film, only the inert gas is supplied in a state in which the plasma is blocked, and the protective film made of ammonium hexafluorosilicate is evaporated and removed.

Wherein the temperature of the chuck is controlled to 80 to 120 degrees, the heating temperature of the showerhead is 100 to 200 degrees, and the heating temperature of the inner wall surface of the chamber is 80 to 100 degrees Celsius .

A dry scrubber for selectively removing polysilicon, characterized in that the hydrogen containing gas comprises H ₂ or NH ₃ or H ₂ O.

According to the invention, the silicon formed on the substrate a nitride, the surface of the silicon oxide hexafluoro silicic acid ammonium _{((NH 4) 2 SiF 6} ) is changed into a solid layer, a polyester by using a silicate ammonium solid layer as a hexafluoro with a protective film There is an effect that a dry cleaning apparatus and method capable of selectively etching silicon can be provided.

1 is a view illustrating a dry cleaning method for selectively removing polysilicon according to an embodiment of the present invention, and FIG.
FIG. 2 is a diagram exemplifying supply timings of an RF power source and a gas in an embodiment of the present invention,
FIG. 3 is a view showing a reaction mechanism of dry cleaning according to an embodiment of the present invention, and FIG.
4 illustrates a dry cleaning apparatus for selectively removing polysilicon according to an embodiment of the present invention.

It is to be understood that the specific structural or functional description of embodiments of the present invention disclosed herein is for illustrative purposes only and is not intended to limit the scope of the inventive concept But may be embodied in many different forms and is not limited to the embodiments set forth herein.

The embodiments according to the concept of the present invention can make various changes and can take various forms, so that the embodiments are illustrated in the drawings and described in detail herein. It should be understood, however, that it is not intended to limit the embodiments according to the concepts of the present invention to the particular forms disclosed, but includes all modifications, equivalents, or alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms may be named for the purpose of distinguishing one element from another, for example, without departing from the scope of the right according to the concept of the present invention, the first element may be referred to as a second element, The component may also be referred to as a first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Other expressions that describe the relationship between components, such as "between" and "between" or "neighboring to" and "directly adjacent to" should be interpreted as well.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like are used to specify that there are features, numbers, steps, operations, elements, parts or combinations thereof described herein, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning of the context in the relevant art and, unless explicitly defined herein, are to be interpreted as ideal or overly formal Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating a dry cleaning method for selectively removing polysilicon according to an embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating an example of timing of supplying RF power and gas in an embodiment of the present invention. FIG. 3 is a view showing a reaction mechanism of dry cleaning according to an embodiment of the present invention, and FIG. 4 is a view illustrating a dry cleaning apparatus for selectively removing polysilicon according to an embodiment of the present invention.

Referring to FIGS. 1 to 4, a dry cleaning method for selectively removing polysilicon according to an embodiment of the present invention includes forming a protective film (S100), removing polysilicon (S200), and removing a protective film (S300) .

A fluorine-containing gas, a hydrogen-containing gas, and an inert gas are defined before describing a specific configuration of the dry cleaning method for selectively removing polysilicon according to an embodiment of the present invention. For example, the fluorine-containing gas may be, but is not limited to, NF ₃ . For example, the hydrogen containing gas may include, but is not limited to, H ₂ or NH ₃ or H ₂ O. For example, the inert gas may include, but is not limited to, N ₂ , Ar, and He.

In addition, the substrate 40 may have a silicon material, and the substrate 40 is essentially formed with heterogeneous patterns of at least one of silicon oxide and silicon nitride and polysilicon.

In the protective film forming step S100, the substrate 40, which is disposed on the chuck 20 inside the chamber 10 and on which the silicon oxide, the silicon nitride, and the polysilicon are formed, A process is performed in which a fluorine-containing gas and a hydrogen-containing gas in a non-plasma state are supplied to change the surface of silicon oxide and nitride nitride to ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ) to form a protective film.

An exemplary configuration of the protective film forming step S100 will be described below.

First, a process of disposing the substrate 40 on the chuck 20 inside the chamber 10 is performed. For example, the substrate 40 can be transported and placed in the chuck 20 inside the chamber 10 by a transporting device (not shown). The substrate 40 may be in a heated state and a chuck heating unit 30 may be used to control the chuck 20 on which the substrate 40 is disposed to have a temperature of 80 to 120 degrees. have. Since the substrate 40 is placed in contact with the chuck 20, the substrate 40 is heated to a temperature corresponding to the heating temperature of the chuck 20. [

Next, a process of injecting the fluorine-containing gas into the plasma generating region is performed. For example, the fluorine-containing gas can be injected from the top of the chamber 10 into the plasma generation region, and the RF electrode 60 disposed in the upper region of the chamber 10 is supplied with the fluorine- The first supply path 62 may be provided.

Next, a process of generating a plasma in the plasma generating region by applying the RF power source 50 is performed. For example, the RF electrode 60 may be disposed on the upper side of the chamber 10, and the showerhead 70 may be disposed on the lower side of the chamber 10 with the plasma generation region interposed therebetween. May be electrically connected to the RF electrode 60 and the cathode may be electrically connected to the showerhead 70. When the RF power source 50 is applied, the fluorine-containing gas injected into the RF electrode 60 and the showerhead 70 is radiated by the plasma reaction and is supplied to the second supply path 72 provided in the showerhead 70, To the substrate (40).

Next, a process of directly injecting the hydrogen-containing gas into the showerhead 70 without plasma processing and supplying the hydrogen-containing gas to the substrate 40 is performed. For example, in addition to the second supply path 72 for providing the path through which the radicalized fluorine-containing gas passes, the showerhead 70 disposed under the plasma generation region is further provided with a passage through which the hydrogen- And the second supply path 72 and the third supply path 74 may be configured to have physically distinct paths.

Next, the plasma-treated fluorine-containing gas and the hydrogen-containing gas that have not been subjected to the plasma treatment react only with silicon oxide and silicon nitride among the silicon oxide, silicon nitride, and polysilicon formed on the substrate 40, and hexafluorosilicic acid The process of producing ammonium is carried out. For example, ammonium hexafluorosilicate can be produced as a solid layer, and the silicon oxide and silicon nitride present on the surface of the substrate 40 can be replaced with an ammonium hexafluorosilicate solid layer.

The process by which the silicon oxide is changed to ammonium hexafluorosilicate is described as follows.

2 NH ₄ F (g) + ₄ HF (g) + SiO ₂ = (NH ₄ ) ₂ SiF ₆ (g) + 2H ₂ O

For example, the RF power source for plasma-forming the fluorine-containing gas and the fluorine-containing gas is continuously supplied in the protective film forming step S100 and the polysilicon removing step S200, and the hydrogen- And may be configured to be supplied in a time range of 1 to 10 seconds. According to this structure, it is possible to minimize the thickness of the (NH ₄ ) ₂ SiF ₆ solid layer serving as a protective film for protecting silicon oxide and silicon nitride in the process of selectively etching the polysilicon, and more preferably, The supply time T1 of the gas may be 6 seconds or less.

In the polysilicon removal step (S200), the supply of the hydrogen-containing gas is stopped, and the fluorine-containing gas in the plasma state is continuously supplied to perform the process of selectively removing the polysilicon with the fluorine radical.

In the protective film removing step (S300), a process of removing the protective film made of ammonium hexafluorosilicate is performed through heat treatment. In this process, the inert gas may be supplied and the non-sulfur gas may be continuously supplied during the entire process, that is, the protective film forming step (S100), the polysilicon removing step (S200), and the protective film removing step (S300).

The process of vaporization and removal of ammonium hexafluorosilicate by heat treatment will be described as follows.

_{(NH 4) 2 SiF 6 (} g) = SiF 4 (g) + 2NH 3 (g) + 2HF (g)

For example, the protective film forming step S100, the polysilicon removing step S200, and the protecting film removing step S300 may be successively performed in an in-situ cleaning method in the same chamber.

For example, in the step of removing the protective film (S300), only the inert gas may be supplied in a state in which the plasma is shut off to evaporate and remove the protective film made of ammonium hexafluorosilicate.

For example, the temperature of the chuck 20 is controlled at 80 to 120 degrees, and the heating temperature of the shower head providing the path for supplying the fluorine-containing gas and the hydrogen-containing gas in the plasma state is 100 to 200 degrees, The heating temperature of the wall surface may be 80-100 degrees.

4, a dry cleaning apparatus for selectively removing polysilicon according to an embodiment of the present invention includes a chamber 10, a chuck 20, a chuck heating unit 30, an RF electrode 60, and a shower And a head 70. It should be noted that other components than those shown in FIG. 4 may be included in the dry scrubber, but components that are less relevant to the features of the present invention are omitted from FIG.

The description of the method described above may be applied to a device, and redundant descriptions are omitted as much as possible.

The chamber 10 provides a space in which the entire process of selectively removing only polysilicon from among silicon oxide, silicon nitride, and polysilicon formed on the substrate 40 is performed.

The chuck 20 is a component that is provided inside the chamber 10 and on which the substrate 40 to be processed is disposed.

The chuck heating section 30 is a component that heats the chuck 20.

The RF electrode 60 is disposed in an upper region inside the chamber 10 and is provided with a first supply path 62 through which an RF power source 50 for plasma generation is applied and which is a path of a fluorine containing gas or an inert gas .

The shower head 70 is electrically connected to the ground terminal of the RF power source 50 and is spaced apart from the RF electrode 60 with the plasma generation region therebetween. The second supply path 72 and the second supply path 72 are physically separated from each other. Since the showerhead 70 is connected to the ground terminal of the RF power source 50 and is grounded, only the reactive radical components can pass through while suppressing the ion component injected into the substrate 40 to the utmost. The second supply path 72 is plasma-treated in the plasma generating region to provide a path through which the radicalized fluorine-containing gas is supplied to the substrate 40, and a third supply path 72, which is physically separated from the second supply path 72, (74) provides a path through which a non-plasma-treated hydrogen-containing gas is supplied to the substrate (40). The second supply path 72 may be used as a supply path of the inert gas.

Under such a configuration, the substrate 40 is heated in response to the heating temperature of the chuck 20 heated by the chuck heating section 30. [

The fluorine-containing gas containing at least NF ₃ that has passed through the first supply path 62 is plasma-treated by the RF power source 50 and supplied to the substrate 40 via the second supply path 72, NH ₃ is supplied to the substrate 40 in a state that the hydrogen-containing gas is not subjected to the plasma treatment through the third supply path 74 so that the surface of the silicon oxide and the silicon nitride selectively etch the polysilicon, silicate ammonium hexafluorophosphate to the function is changed to _{((NH 4) 2 SiF 6} ).

Here, in the dry cleaning apparatus for selectively removing polysilicon according to an embodiment of the present invention, in the process of forming the protective film, silicon oxide (SiO 2) is added to the substrate 40 through the first supply path 62 and the second supply path 72, Containing gas in a non-plasma state is supplied to the substrate 40 through the third supply path 74 so that the surface of the silicon oxide and the nitride nitride is supplied to the substrate 40 through a hexafluoro (NH ₄ ) ₂ SiF ₆ ) to produce a protective film. In the polysilicon removal process, the supply of the hydrogen-containing gas is stopped and the fluorine-containing gas in the plasma state is continuously supplied to remove the polysilicon from the fluorine radical In the process of removing the protective film, the protective film made of ammonium hexafluorosilicate can be removed by evaporation through heat treatment.

For example, the RF power source 50 for plasma-forming the fluorine-containing gas and the fluorine-containing gas is continuously supplied in the process of forming the protective film and the process of removing polysilicon, and the hydrogen- Lt; / RTI > According to this structure, it is possible to minimize the thickness of the (NH4) 2SiF6 solid layer serving as a protective film for protecting the silicon oxide and the silicon nitride in the process of selectively etching the polysilicon, and more preferably, The time T1 may be less than or equal to 6 seconds.

The process by which the silicon oxide is changed to ammonium hexafluorosilicate is described as follows.

2 NH ₄ F (g) + ₄ HF (g) + SiO ₂ = (NH ₄ ) ₂ SiF ₆ (g) + 2H ₂ O

The process of vaporization and removal of ammonium hexafluorosilicate by heat treatment will be described as follows.

_{(NH 4) 2 SiF 6 (} g) = SiF 4 (g) + 2NH 3 (g) + 2HF (g)

For example, the protective film forming process, the polysilicon removing process, and the protective film removing process can be successively performed in an in-situ cleaning method in the same chamber.

For example, the temperature of the chuck 20 is controlled at 80 to 120 degrees, and the heating temperature of the shower head providing the path for supplying the fluorine-containing gas and the hydrogen-containing gas in the plasma state is 100 to 200 degrees, The heating temperature of the wall surface may be 80-100 degrees.

As described in detail above, according to the present invention, the surface of silicon nitride and silicon oxide formed on the substrate is changed to a solid layer of ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ), and the ammonium hexafluorosilicate solid layer Is used as a protective film, polysilicon can be selectively etched.

10: chamber
20: chuck
30: chuck heating section
40: substrate
50: RF power
60: RF electrode
62: first supply path
70: Shower head
72: second supply path
74: Third supply path
S100:
S200: Polysilicon removal step
S300: Step of removing the protective film

Claims (14)

A plasma-state fluorine-containing gas reacting with the silicon oxide, the silicon nitride, and a hydrogen-containing gas in a non-plasma state are supplied to a substrate on which a silicon oxide, a silicon nitride, and a polysilicon are formed, Silicon oxide, a protective film forming step of changing the surface of the nitride nitride to ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ) to form a protective film;
A polysilicon removing step of stopping supply of the hydrogen-containing gas and continuously supplying the fluorine-containing gas in the plasma state to selectively remove the polysilicon with a fluorine radical; And
And a protective film removing step of removing the protective film made of ammonium hexafluorosilicate through heat treatment. The method according to claim 1,
The RF power source for converting the fluorine-containing gas and the fluorine-containing gas into plasma is continuously supplied in the protective film forming step and the polysilicon removing step,
Wherein the hydrogen-containing gas is supplied only in the protective film forming step. 3. The method of claim 2,
Wherein the time for supplying the hydrogen-containing gas is 1 to 10 seconds. The method according to claim 1,
Wherein the step of forming the protective film, the step of removing the polysilicon, and the step of removing the protective film are continuously performed in an in-situ cleaning method in the same chamber. The method according to claim 1,
Wherein the protective film is removed by evaporating a protective film made of ammonium hexafluorosilicate by supplying only an inert gas in a state in which the plasma is blocked, thereby selectively removing the polysilicon. The method according to claim 1,
Wherein the temperature of the chuck is controlled to 80 to 120 degrees and the heating temperature of the showerhead providing the path for supplying the fluorine-containing gas and the hydrogen-containing gas in the plasma state is 100 to 200 degrees, Is 80 to < RTI ID = 0.0 > 100. ≪ / RTI > The method according to claim 1,
Wherein the hydrogen containing gas comprises H ₂ or NH ₃ or H ₂ O. A chuck provided in the chamber and having a substrate on which silicon oxide, silicon nitride, and polysilicon are formed;
A chuck heating section for heating the chuck;
An RF electrode having a first supply path to which a RF power source for plasma generation is applied and which provides a path through which a fluorine-containing gas is supplied; And
A second supply path for supplying a path for supplying a plasma-treated fluorine-containing gas from the plasma generation region to the substrate, the plasma generation region being connected to a ground terminal of the RF power source, And a showerhead having a third supply path physically separated from the second supply path, the shower head having a path for supplying a hydrogen-containing gas to the substrate,
Supplying a fluorine-containing gas in a plasma state, which reacts with the silicon oxide and the silicon nitride, to the substrate through the first supply path and the second supply path in the process of forming the protective film, Containing gas is supplied to the surface of the silicon nitride and the nitride nitride to change the surface of the silicon nitride and the nitride nitride to ammonium hexafluorosilicate ((NH ₄ ) ₂ SiF ₆ ) to form a protective film,
The supply of the hydrogen-containing gas is stopped and the fluorine-containing gas in the plasma state is continuously supplied to selectively remove the polysilicon with the fluorine radical,
And removing the protective film made of ammonium hexafluorosilicate through heat treatment in the process of removing the protective film, wherein the polysilicon is selectively removed. 9. The method of claim 8,
The RF power source for converting the fluorine-containing gas and the fluorine-containing gas into plasma is continuously supplied in the protective film forming process and the polysilicon removing process,
Wherein the hydrogen-containing gas is supplied only during the process of forming the protective film. 10. The method of claim 9,
Wherein the time for supplying the hydrogen-containing gas is from 1 to 10 seconds. 8. The method of claim 7,
Wherein the polysilicon removal process and the protective film removal process are continuously performed in an in-situ cleaning process in the same chamber. The method according to claim 1,
Wherein the protective film is selectively removed by evaporating a protective film made of ammonium hexafluorosilicate by supplying only an inert gas in a state where the plasma is blocked. 9. The method of claim 8,
Wherein the temperature of the chuck is controlled to 80 to 120 degrees, the heating temperature of the showerhead is 100 to 200 degrees, and the heating temperature of the inner wall surface of the chamber is 80 to 100 degrees. Cleaning device. 9. The method of claim 8,
Characterized in that the hydrogen containing gas comprises H ₂ or NH ₃ or H ₂ O.

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