Yttrium fluoride film as well as preparation method and application thereof

Abstract

The invention provides a preparation method of an yttrium fluoride film, which comprises the following steps: S1) placing a substrate in an atomic layer deposition device, introducing a precursor containing yttrium and fluorine at the same time, and forming a film layer on the surface of the substrate after reaction; the film layer is subjected to purging; and S2) introducing an oxygen source into the atomic layer deposition device to react with the film layer, and purging again to obtain the yttrium fluoride film. According to different reactant precursors, the invention further provides a preparation method of the yttrium fluoride film. The invention further provides application of the yttrium fluoride thin film. According to the preparation method of the yttrium fluoride thin film, an atomic layer deposition method is utilized to alternately introduce a metal organic source and an oxygen source into a reaction chamber, and a film is formed through a self-limiting reaction. The prepared yttrium fluoride film is uniform and compact, no toxic gas is introduced, and the yttrium fluoride film has high safety.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an yttrium fluoride film, a preparation method thereof and an application thereof. Background Art

[0002] Yttrium fluoride thin film has a low refractive index of only about 1.4, is non-toxic, and has a low absorption rate in a wide spectral range. The interference optical film stack composed of it and high refractive index materials is an important material for making optical components such as one-dimensional photonic crystals and infrared interference filters. At present, the commonly used preparation methods of yttrium fluoride thin films include evaporation deposition, magnetron sputtering, and chemical methods.

[0003] Magnetron sputtering technology is a low-temperature, high-speed thin film deposition technology that is widely used in industrial production and scientific research. When using magnetron sputtering technology to prepare thin films using yttrium fluoride targets, it is easy to cause the loss of anionic fluoride ions, increased absorption, refractive index distortion, and functional failure. At the same time, the internal stress of the film is unstable, which can easily cause the film to break, fall off, and crack, leading to structural failure. Therefore, in the process of preparing yttrium fluoride thin films by magnetron sputtering, reactive gas is generally used to supplement fluoride ions. If fluorine gas is used, it is highly toxic. If perfluorocarbon is used, impurity ions such as C will be introduced into the film, greatly reducing the protective effect. For samples with structures, the thin film deposited by physical vapor deposition (PVD) cannot guarantee the uniformity of the coating.

[0004] Therefore, it is of great significance to provide a non-toxic preparation method that ensures uniform and dense yttrium fluoride film. Summary of the invention

[0005] The technical problem solved by the present invention is to provide a method for preparing yttrium fluoride film. In the process of preparing yttrium fluoride film, no toxic gas containing fluorine is used, and the prepared yttrium fluoride film is uniform and dense. Furthermore, the yttrium fluoride film prepared by the present application has strong anti-corrosion performance and structural stability.

[0006] In view of this, the present application provides a method for preparing an yttrium fluoride thin film, comprising the following steps:

[0007] S1) placing a substrate in an atomic layer deposition device, introducing precursors containing both yttrium and fluorine, and forming a film layer on the surface of the substrate after reaction; and purging the film layer;

[0008] S2) introducing an oxygen source into the atomic layer deposition device to react with the film layer, and then purging again to obtain an yttrium fluoride film.

[0009] Preferably, step S2) further includes:

[0010] Taking step S1) and step S2) as a preparation cycle, repeating the preparation cycle n times, where n≥1;

[0011] And / or, in step S1), before introducing the precursor containing both yttrium and fluorine, the method further comprises: adjusting the temperature of the atomic layer deposition device to 200-500° C. and the pressure to 0.2-1.0 mbar;

[0012] And / or, in step S1), the flow rate of the precursor containing both yttrium and fluorine into the atomic layer deposition device is 100-500sccm, and the introduction time is 1-15s; the heating temperature of the source bottle of the precursor containing both yttrium and fluorine is 80-120°C, and the heating temperature of the source pipeline is 90-160°C.

[0013] Preferably, the precursor containing both yttrium and fluorine comprises yttrium hexafluoroacetylacetonate, and the oxygen source comprises ozone or oxygen plasma.

[0014] Preferably, in step S2), the oxygen source is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s;

[0015] And / or, in step S1), the gas used for purging is nitrogen or argon, and the purging time is 5 to 50 seconds; in step S2), the gas used for re-purging is nitrogen or argon, and the purging time is 5 to 50 seconds.

[0016] The present application also provides a method for preparing an yttrium fluoride thin film, comprising the following steps:

[0017] S1) placing a substrate in an atomic layer deposition device, introducing a first precursor, and forming a film layer on the surface of the substrate after reaction; and performing a first purge on the film layer;

[0018] S2) introducing an oxygen source into the atomic layer deposition device to react with the film layer, and performing a second purge after the reaction;

[0019] S3) introducing a second precursor into the atomic layer deposition device, reacting with the film layer obtained by the reaction in step S2), and then performing a third purge;

[0020] S4) introducing an oxygen source into the atomic layer deposition device to react with the film layer obtained by the reaction in step S3) and then performing a fourth purge to obtain an yttrium fluoride film;

[0021] The first precursor is selected from a yttrium-containing precursor or a fluorine-containing precursor, and correspondingly, the second precursor is selected from a fluorine-containing precursor or a yttrium-containing precursor.

[0022] Preferably, step S4) further includes:

[0023] Taking step S1), step S2), step S3) and step S4) as a preparation cycle, repeating the preparation cycle n times, where n≥1;

[0024] And / or, in step S1), before the first precursor is introduced, the method further comprises: adjusting the temperature of the atomic layer deposition device to 200-400° C. and the pressure to 0.2-10 mbar;

[0025] And / or, the flow rate of the fluorine-containing precursor or the yttrium-containing precursor into the atomic layer deposition device is independently 100-500sccm, and the introduction time is independently 1-15s; the heating temperature of the source bottle of the yttrium-containing precursor is 120-170°C, and the heating temperature of the source pipeline is 150-200°C.

[0026] Preferably, the yttrium-containing precursor includes yttrium trisdiketonate, the fluorine-containing precursor includes hexafluoroacetylacetone, and the oxygen source includes ozone or oxygen plasma.

[0027] Preferably, in step S2), the oxygen source is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s; in step S4), the oxygen source is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s;

[0028] And / or, in step S1), the gas used for the first purge is argon or nitrogen, and the time of the first purge is 5 to 50 s; in step S2), the gas used for the second purge is argon or nitrogen, and the time of the second purge is 5 to 50 s; in step S3), the gas used for the third purge is argon or nitrogen, and the time of the third purge is 5 to 50 s; in step S4), the gas used for the fourth purge is argon or nitrogen, and the time of the fourth purge is 5 to 50 s.

[0029] Preferably, the substrate is a hydroxylation-treated substrate.

[0030] The present application also provides an yttrium fluoride film, which is prepared by the preparation method.

[0031] The present application also provides a reaction chamber, comprising a structural component, a yttrium fluoride film is formed on the surface of the structural component, and the yttrium fluoride film is the yttrium fluoride film prepared by the preparation method or the yttrium fluoride film.

[0032] Preferably, the structural component is a spray structure.

[0033] The present application also provides the use of yttrium fluoride film as an anti-corrosion coating on the surface of a structural component, wherein the yttrium fluoride film is the yttrium fluoride film prepared by the preparation method or the yttrium fluoride film.

[0034] The present application provides a method for preparing an yttrium fluoride film, specifically, the substrate is exposed alternately and sequentially to a precursor containing both yttrium and fluorine and an oxygen source reactant, and the yttrium fluoride film is prepared by atomic layer deposition. At the same time, the present application also provides a method for preparing an yttrium fluoride film, specifically, the substrate is exposed alternately and sequentially to a first precursor, an oxygen source, a second precursor and an oxygen source reactant, and the yttrium fluoride film is prepared by atomic layer deposition, wherein the first precursor is selected from a yttrium-containing precursor or a fluorine-containing precursor, and correspondingly, the second precursor The precursor is selected from a fluorine-containing precursor or an yttrium-containing precursor; in the above-mentioned process of preparing the yttrium fluoride film, the precursors of the two paths and the oxygen source are used as reactants, and no toxic fluorine-containing gas is used, thereby ensuring the safety of the deposition of the yttrium fluoride film; the yttrium fluoride film is prepared by atomic layer deposition, so that the film layer is uniform, the surface is dense, and has strong anti-corrosion performance; further, the thickness of the yttrium fluoride film prepared in the present application decreases or decreases slowly in a corrosive environment, and the experimental results show that the thickness of the yttrium fluoride film is reduced by only 1% after 1 hour in a corrosive environment. This shows that the yttrium fluoride film has good structural stability.

[0035] Furthermore, in the process of preparing yttrium fluoride film, the specific selection of precursors and oxygen sources combined with atomic layer deposition are more conducive to obtaining a uniform and dense yttrium fluoride film; and the temperature is low, the environment is good, the film thickness is controllable, and the method is easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of the reaction route of the first method for preparing yttrium fluoride thin film according to the present invention;

[0037] Figure 2 A schematic diagram of the reaction route of the second method for preparing yttrium fluoride thin film according to the present invention;

[0038] Figure 3 This is the XPS spectrum of the yttrium fluoride film prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0039] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0040] In view of the problem that toxic gases are used as reactants in the preparation process of yttrium fluoride thin films in the prior art and the uniformity of the film layer cannot be guaranteed, the present application provides a method for preparing yttrium fluoride thin films, which introduces atomic layer deposition technology and combines specific precursors and oxygen sources to make the preparation method of yttrium fluoride thin films safer, and the film layer is dense, uniform and has strong anti-corrosion performance. Specifically, the present application first provides a method for preparing yttrium fluoride thin films, comprising the following steps:

[0041] S1) placing a substrate in an atomic layer deposition device, introducing precursors containing both yttrium and fluorine, and forming a film layer on the surface of the substrate after reaction; and purging the film layer;

[0042] S2) introducing an oxygen source into the atomic layer deposition device to react with the film layer, and then purging again to obtain an yttrium fluoride film.

[0043] In the present application, the preparation of the yttrium fluoride film includes two technical routes according to the difference of the precursors. The above preparation method is a technical route. In this technical route, the precursor containing both yttrium and fluorine includes yttrium hexafluoroacetylacetonate, and the oxygen source includes ozone or oxygen plasma; in a specific embodiment, the precursor is selected from yttrium hexafluoroacetylacetonate, and the oxygen source is selected from ozone. On this basis, the preparation method of the yttrium fluoride film includes exposing the substrate to yttrium hexafluoroacetylacetonate Y(hfac)3 and ozone alternately and sequentially, thereby preparing the yttrium fluoride film; the chemical reaction formula is as follows: Y(hfac)3+O3→YF3.

[0044] Specifically, in the preparation process of yttrium fluoride thin film, the present application first places a substrate in an atomic layer deposition device, introduces yttrium hexafluoroacetylacetonate, forms a film layer on the surface of the substrate after the reaction, and then purges the film layer; in this process, before introducing yttrium hexafluoroacetylacetonate, adjust the temperature and pressure of the atomic layer deposition device, the temperature is 200-500°C, and the pressure is 0.2-10mbar, specifically, the temperature is 250-450°C, the pressure is 1-8mbar, more specifically, the temperature is 300-400°C, and the pressure is 3-6mbar. The substrate is a substrate capable of realizing film deposition using atomic layer deposition technology, and is a substrate well known to those skilled in the art. Specifically, the substrate may be a semiconductor substrate, including a silicon wafer, a stainless steel substrate, a PVC substrate, an aluminum alloy substrate, and the like; in order to further improve the bonding strength between the film layer and the substrate, the substrate is a substrate that has been treated with hydroxylation, and the hydroxylation treatment is a treatment process well known to those skilled in the art, and this application does not impose any special restrictions on this. The flow rate of the yttrium hexafluoroacetylacetonate introduced is 100 to 500 sccm, and the introduction time is 1 to 15 s. Specifically, the flow rate of the yttrium hexafluoroacetylacetonate introduced is 300 to 400 sccm, and the introduction time is 5 to 10 s. The purging is specifically carried out using an inert gas, nitrogen or argon, to purge residual chemical sources, and the purging time is 5 to 50 s. Specifically, the purging time is 15 to 45 s, and more specifically, the purging time is 20 to 40 s.

[0045] The present application then introduces ozone into the atomic layer deposition device to react with the film layer after the above reaction, and then purges again to obtain an yttrium fluoride film; in this process, the ozone is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s. Specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 800 to 1200 sccm, and the introduction time is 5 to 12 s. More specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 900 to 1000 sccm, and the introduction time is 8 to 10 s. The purge specifically uses inert gas nitrogen or argon to purge residual chemical sources, and the purge time is 5 to 50 s. Specifically, the purge time is 15 to 45 s, and more specifically, the purge time is 20 to 40 s.

[0046] The above process completes an atomic layer deposition process of yttrium fluoride film, and the deposition rate is Specifically, the deposition rate is During the deposition process, the source bottle of yttrium hexafluoroacetylacetonate is heated to 80-120°C, and the source pipeline is heated to 90-160°C. Specifically, the source bottle of yttrium hexafluoroacetylacetonate is heated to 90-100°C, and the source pipeline is heated to 105-150°C; the oxygen source and the delivery pipeline are at room temperature and do not need to be heated.

[0047] The technical route of the above process of this application is as follows: Figure 1 As shown, taking the substrate as a silicon substrate, the yttrium-containing and fluorine-containing precursors as yttrium hexafluoroacetylacetonate Y(hfac)3, and the oxygen source as ozone as an example, the preparation mechanism of the yttrium fluoride film is specifically as follows:

[0048] Step 1: Y(hfac)3 is brought into the reaction chamber of the atomic layer deposition device by an inert gas through a delivery pipeline, and adsorbed on the substrate to form a surface containing hfac - The film layer;

[0049] After purging with inert gas, the excess, unreacted precursor Y(hfac)3 is purged away;

[0050] Step 2: Pass O3 into the membrane layer to react with hfac - Reaction to form Y-CO3 - and some free F - , F - Further replacement of CO3 - With Y + Combined to form YF3, which is deposited on the substrate;

[0051] After purging with inert gas, the by-products after the reaction are purged to obtain a stable YF3 film.

[0052] In the present application, the above-mentioned atomic layer deposition process can be repeated multiple times according to the thickness of the yttrium fluoride film, which can be ≥1 times, ≥10 times, or ≥100 times. The number of repeated cycles is adjusted according to the thickness requirement of the yttrium fluoride film. In a specific embodiment, the above-mentioned atomic layer deposition process is repeated 600 times, thereby obtaining a 30nm yttrium fluoride film.

[0053] The present application also provides a method for preparing an yttrium fluoride thin film, comprising the following steps:

[0054] S1) placing a substrate in an atomic layer deposition device, introducing a first precursor, and forming a film layer on the surface of the substrate after reaction; and performing a first purge on the film layer;

[0055] S2) introducing an oxygen source into the atomic layer deposition device to react with the film layer, and performing a second purge after the reaction;

[0056] S3) introducing a second precursor into the atomic layer deposition device, reacting with the film layer obtained by the reaction in step S2), and then performing a third purge;

[0057] S4) introducing an oxygen source into the atomic layer deposition device to react with the film layer obtained by the reaction in step S3) and then performing a fourth purge to obtain an yttrium fluoride film;

[0058] The first precursor is selected from a yttrium-containing precursor or a fluorine-containing precursor, and correspondingly, the second precursor is selected from a fluorine-containing precursor or a yttrium-containing precursor.

[0059] The above preparation method is another technical route for yttrium fluoride film, which also realizes the preparation of yttrium fluoride film by atomic layer deposition; in the above method, the yttrium-containing precursor includes yttrium tris-diketonate Y(thd)3, the fluorine-containing precursor includes hexafluoroacetylacetone Hhfac, and the oxygen source includes ozone or oxygen plasma. In a specific embodiment, the yttrium-containing precursor is selected from yttrium tris-diketonate Y(thd)3, the fluorine-containing precursor is selected from hexafluoroacetylacetone Hhfac, and the oxygen source is selected from ozone; the fluorine-containing precursor used in this application does not use toxic fluorine sources well known to technicians in this field, such as: TiF4, HF, etc. On this basis, the preparation method of yttrium fluoride film includes alternately and sequentially exposing the substrate to yttrium precursor yttrium trisdiketonate Y(thd)3 (or fluorine precursor hexafluoroacetylacetone (Hhfac)), ozone, fluorine precursor hexafluoroacetylacetone (Hhfac) (or yttrium precursor yttrium trisdiketonate Y(thd)3) ​​and ozone reactants, and the specific chemical reaction formula is: Y(thd)3+O3+Hhfac+O3→YF3 or Hhfac+O3+Y(thd)3+O3→YF3.

[0060] Specifically, in the preparation process of yttrium fluoride film, taking the reactants as yttrium tris(di-ketonate) Y(thd)3, ozone, hexafluoroacetylacetone (Hhfac) and ozone introduced into an atomic layer deposition device in sequence as an example, the present application first places a substrate in an atomic layer deposition device, introduces yttrium tris(di-ketonate), forms a film layer on the surface of the substrate after the reaction, and then performs a first purge on the film layer; in this process, before introducing yttrium tris(di-ketonate), adjust the temperature and pressure of the atomic layer deposition device, the temperature is 200-400°C, and the pressure is 0.2-10mbar, specifically, the temperature is 250-350°C, and the pressure is 1-8mbar. The substrate is a substrate capable of realizing film deposition using atomic layer deposition technology, and is a substrate well known to those skilled in the art. Specifically, the substrate may be a semiconductor substrate, including a silicon wafer, a stainless steel substrate, a PVC substrate, an aluminum alloy substrate, and the like; in order to further improve the bonding strength between the film layer and the substrate, the substrate is a substrate that has been treated with hydroxylation, and the hydroxylation treatment is a treatment process well known to those skilled in the art, and this application does not impose any special restrictions on this. The flow rate of the yttrium tris-diketonate is 100-500sccm, and the time of introduction is 1-15s. Specifically, the flow rate of the yttrium tris-diketonate is 300-400sccm, and the time of introduction is 5-10s. The first purge is specifically carried out using an inert gas, nitrogen or argon, to purge residual chemical sources. The time of the first purge is 5-50s. Specifically, the time of the first purge is 15-45s, and more specifically, the time of the first purge is 20-40s.

[0061] The present application further introduces ozone into the atomic layer deposition device to react with the film layer after the above reaction, and performs a second purge after the reaction; in this process, the ozone is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s. Specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 800 to 1200 sccm, and the introduction time is 5 to 12 s. More specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 900 to 1000 sccm, and the introduction time is 8 to 10 s. The second purge specifically uses inert gas nitrogen or argon to purge residual chemical sources. The second purge time is 5 to 50 s. Specifically, the second purge time is 15 to 45 s. More specifically, the second purge time is 20 to 40 s.

[0062] According to the present invention, hexafluoroacetylacetone is then introduced into the atomic layer deposition device, and a third purge is performed after reacting with the film layer obtained by the above reaction; in this process, the flow rate of the hexafluoroacetylacetone introduced is 100-500sccm, and the introduction time is 1-20s. Specifically, the flow rate of the hexafluoroacetylacetone introduced is 300-400sccm, and the introduction time is 5-15s; the hexafluoroacetylacetone is introduced and reacts with the film layer. The third purge specifically uses inert gas nitrogen or argon to purge residual chemical sources, and the third purge time is 5-50s. Specifically, the third purge time is 15-45s, and more specifically, the third purge time is 20-40s.

[0063] Finally, ozone is introduced into the atomic layer deposition device to react with the film layer after the above reaction, and a fourth purge is performed after the reaction; in this process, the ozone is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s. Specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 800 to 1200 sccm, and the introduction time is 5 to 12 s. More specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 900 to 1000 sccm, and the introduction time is 8 to 10 s. The fourth purge is specifically carried out using an inert gas nitrogen or argon to purge residual chemical sources. The fourth purge time is 5 to 50 s. Specifically, the fourth purge time is 15 to 45 s. More specifically, the fourth purge time is 20 to 40 s.

[0064] The above process completes an atomic layer deposition process of yttrium fluoride film, and the deposition rate is Specifically, the deposition rate is During the deposition process, the heating temperature of the source bottle of the yttrium precursor is 120-170°C, and the heating temperature of the source pipeline is 150-200°C. The source bottle and source pipeline of the fluorine precursor are not heated. Specifically, the heating temperature of the source bottle of the yttrium precursor is 140-150°C, and the heating temperature of the source pipeline is 155-180°C. The oxygen source and the delivery pipeline are at room temperature and do not need to be heated.

[0065] The technical route of the above process of this application is as follows: Figure 2 As shown, taking the substrate as a silicon substrate, the yttrium precursor as yttrium tridiketonate Y(thd)3, the oxygen source as ozone, and the fluorine precursor as hexafluoroacetylacetone (Hhfac) as an example, the preparation mechanism of the yttrium fluoride film is specifically as follows:

[0066] Step 1: Y(thd)3 is brought into the reaction chamber of the atomic layer deposition device by an inert gas through a delivery pipeline, and adsorbed on the substrate to form a surface containing thd - The film layer;

[0067] After purging with inert gas, the excess, unreacted precursor Y(thd)3 is purged away;

[0068] Step 2: Pass O3 into the membrane layer to react with thd - Reaction to form Y-CO3 - ;

[0069] After purging with inert gas, the excess reaction by-products are purged away;

[0070] Step 3: introduce Hhfac and physically adsorb it on the membrane surface;

[0071] After purging with inert gas, the excess precursor Hhfac is purged away;

[0072] Step 4: Add O3 to form Y-CO3 - and F - , F - Further replacement of CO3 - , forming a YF3 thin film, which is deposited on the substrate surface;

[0073] After purging with inert gas, the excess reaction by-products are purged to obtain a stable YF3 film.

[0074] In the present application, the above atomic layer deposition process can be repeated multiple times according to the thickness of the yttrium fluoride film, which can be ≥1 time, ≥10 times, or ≥100 times, and is adjusted according to the thickness requirement of the yttrium fluoride film; in a specific embodiment, the above atomic layer deposition process is repeated 600 times, thereby obtaining a 30nm yttrium fluoride film.

[0075] In the above technical route, the reactants are sequentially introduced into an atomic layer deposition device in the order of yttrium tris-diketonate-ozone-hexafluoroacetylacetone-ozone to prepare an yttrium fluoride film. Similarly, the reactants can also be sequentially introduced into an atomic layer deposition device in the order of hexafluoroacetylacetone-ozone-yttrium tris-diketonate-ozone to prepare an yttrium fluoride film. The specific preparation method is as follows:

[0076] The present application first places a substrate in an atomic layer deposition device, introduces hexafluoroacetylacetone, forms a film layer on the surface of the substrate after the reaction, and then performs a first purge on the film layer; in this process, before introducing hexafluoroacetylacetone, adjust the temperature and pressure of the atomic layer deposition device, the temperature is 200-400°C, the pressure is 0.2-10mbar, specifically, the temperature is 250-350°C, and the pressure is 1-8mbar. The substrate is a substrate capable of film deposition using atomic layer deposition technology, and is a substrate well known to those skilled in the art. Specifically, the substrate can be a semiconductor substrate, including a silicon wafer, a stainless steel substrate, a PVC substrate, an aluminum alloy substrate, and the like; in order to further improve the bonding strength between the film layer and the substrate, the substrate is a hydroxylated substrate, and the hydroxylation treatment is a treatment process well known to those skilled in the art, and the present application does not impose any special restrictions on this. The flow rate of the hexafluoroacetylacetone is 100-500 sccm, and the time of the hexafluoroacetylacetone is 1-15 s. Specifically, the flow rate of the hexafluoroacetylacetone is 300-400 sccm, and the time of the hexafluoroacetylacetone is 5-10 s. The first purge is performed by using an inert gas, nitrogen or argon, to purge the residual chemical source. The time of the first purge is 5-50 s. Specifically, the time of the first purge is 15-45 s. More specifically, the time of the first purge is 20-40 s.

[0077] The present application further introduces ozone into the atomic layer deposition device to react with the film layer after the above reaction, and performs a second purge after the reaction; in this process, the ozone is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s. Specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 800 to 1200 sccm, and the introduction time is 5 to 12 s. More specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 900 to 1000 sccm, and the introduction time is 8 to 10 s. The second purge specifically uses inert gas nitrogen or argon to purge residual chemical sources. The second purge time is 5 to 50 s. Specifically, the second purge time is 15 to 45 s. More specifically, the second purge time is 20 to 40 s.

[0078] According to the present invention, yttrium tris-diketonate is then introduced into the atomic layer deposition device, and the third purge is performed after reacting with the film layer obtained by the above reaction; in this process, the flow rate of the yttrium tris-diketonate is 100-500sccm, and the introduction time is 1-20s, specifically, the flow rate of the yttrium tris-diketonate is 300-400sccm, and the introduction time is 5-15s; the yttrium tris-diketonate is introduced and reacts with the film layer. The third purge specifically uses inert gas nitrogen or argon to purge residual chemical sources, and the time of the third purge is 5-50s, specifically, the time of the third purge is 15-45s, and more specifically, the time of the third purge is 20-40s.

[0079] Finally, ozone is introduced into the atomic layer deposition device to react with the film layer after the above reaction, and a fourth purge is performed after the reaction; in this process, the ozone is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s. Specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 800 to 1200 sccm, and the introduction time is 5 to 12 s. More specifically, the ozone is introduced into the atomic layer deposition device at a flow rate of 900 to 1000 sccm, and the introduction time is 8 to 10 s. The fourth purge is specifically carried out using an inert gas nitrogen or argon to purge residual chemical sources. The fourth purge time is 5 to 50 s. Specifically, the fourth purge time is 15 to 45 s. More specifically, the fourth purge time is 20 to 40 s.

[0080] The above process completes an atomic layer deposition process of yttrium fluoride film, and the deposition rate is Specifically, the deposition rate is During the deposition process, the heating temperature of the source bottle of the yttrium precursor is 120-170°C, and the heating temperature of the source pipeline is 150-200°C. The source bottle and source pipeline of the fluorine precursor are not heated. Specifically, the heating temperature of the source bottle of the yttrium precursor is 140-150°C, and the heating temperature of the source pipeline is 155-180°C. The oxygen source and the delivery pipeline are at room temperature and do not need to be heated.

[0081] In the above process of the present application, taking the substrate as a silicon substrate, the yttrium precursor as yttrium tridiketonate Y(thd)3, the oxygen source as ozone, and the fluorine precursor as hexafluoroacetylacetone (Hhfac) as an example, the preparation mechanism of the yttrium fluoride film is specifically as follows:

[0082] Step 1: Hhfac is brought into the reaction chamber of the atomic layer deposition device by an inert gas through a delivery pipeline, and adsorbed on the substrate to form a surface containing hfac - The film layer;

[0083] After purging with inert gas, the excess, unreacted precursor Hhfac is purged away;

[0084] Step 2: Pass O3 into the membrane layer to react with hfac - Reaction to form Y-CO3 - ;

[0085] After purging with inert gas, the excess reaction by-products are purged away;

[0086] Step 3: Y(thd)3 is introduced and physically adsorbed on the surface of the membrane layer;

[0087] After purging with inert gas, the excess precursor Y(thd)3 is purged away;

[0088] Step 4: Add O3 to form Y-CO3 - and F - , F - Further replacement of CO3 - , forming a YF3 thin film, which is deposited on the substrate surface;

[0089] After purging with inert gas, the excess reaction by-products are purged to obtain a stable YF3 film.

[0090] In the present application, the above atomic layer deposition process can be repeated multiple times according to the thickness of the yttrium fluoride film, which can be ≥1 time, ≥10 times, or ≥100 times, and is adjusted according to the thickness requirement of the yttrium fluoride film; in a specific embodiment, the above atomic layer deposition process is repeated 600 times, thereby obtaining a 30nm yttrium fluoride film.

[0091] In the present application, the atomic layer deposition device is an atomic layer deposition device well known to those skilled in the art, that is, the atomic layer deposition device can realize atomic layer deposition, and the present application does not impose any special restrictions on its specific structure.

[0092] The present application also provides an yttrium fluoride film, which is prepared by the above method.

[0093] The surface of the yttrium fluoride film prepared in the present application is dense and uniform, and the thickness uniformity is less than 3%. The thickness uniformity is the property that the thickness of the film remains relatively consistent. The lower the value, the better the thickness uniformity. Thickness uniformity is a film property that cannot be ignored. The yttrium fluoride film prepared by the atomic layer deposition method in the present application has good thickness uniformity, which also makes the structural stability of the film good.

[0094] The present application also provides a reaction chamber, comprising a structural component, a yttrium fluoride film is formed on the surface of the structural component, and the yttrium fluoride film is the yttrium fluoride film prepared by the above scheme.

[0095] In the present application, there is no special restriction on the structural components in the reaction chamber, as long as the structural components need anti-corrosion protection, a yttrium fluoride film can be formed on the surface thereof; for example, the structural component can be a spray device, specifically a shower plate, and the yttrium fluoride film can be uniformly deposited on the surface of the shower head and in the spray holes. The yttrium fluoride film has high thickness uniformity and good density, and will not affect the spraying effect of the spray holes of the shower head, further achieving environmental protection, and can effectively protect against the erosion of halogen-containing plasma and fluorine-containing gas.

[0096] Furthermore, the present application also provides the use of yttrium fluoride film as an anti-corrosion coating on the surface of a structural component.

[0097] The yttrium fluoride film prepared in the present application has good anti-corrosion effect and can be applied to the surfaces of various structural components in the chamber of the semiconductor process technology. The structural components can be structural components made of stainless steel materials, pure metal materials, aluminum alloy materials, etc. The yttrium fluoride film is formed on the surface of all or part of the above-mentioned structural components by atomic layer deposition method to achieve corrosion resistance.

[0098] The present application provides a method for preparing an yttrium fluoride thin film, which essentially utilizes an atomic layer deposition method (ALD deposition method) to achieve the preparation of the yttrium fluoride thin film, adopts two paths of metal organic source precursors and an oxygen source as reaction sources, does not use toxic fluorine-containing gases, and ensures the safety of thin film deposition; and the preparation process has low temperature, is environmentally friendly, and has controllable film thickness, and the process method is easy to implement; the yttrium fluoride thin film prepared by ALD has a uniform film layer, a dense surface, and strong anti-corrosion performance, especially for structured samples, the atomic layer deposition technology can ensure that the positions that need to be protected are evenly covered with the yttrium fluoride thin film.

[0099] In order to further understand the present invention, the preparation method of the yttrium fluoride film provided by the present invention is described in detail below in conjunction with examples, and the protection scope of the present invention is not limited by the following examples.

[0100] Example 1

[0101] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0102] The wafer was sent into the reaction chamber, and then the chamber was evacuated. The pressure was adjusted at 1 mbar by a butterfly valve, and the temperature was controlled at 300 °C. Yttrium hexafluoroacetylacetonate was introduced, and the carrier gas flow rate was set to 300 sccm for 5 seconds, and then nitrogen was introduced for 15 seconds. Ozone was then introduced for 2 seconds with a flow rate of 1000 sccm, and finally nitrogen was introduced for 10 seconds. Thus, a sub-cycle of yttrium fluoride deposition was completed, and the deposition rate was During the deposition process, the source bottle of the yttrium hexafluoroacetylacetonate precursor is heated to 100°C, and the source pipeline is heated to 120°C; the oxygen source and the delivery pipeline are at room temperature and do not need to be heated;

[0103] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0104] The experimental results show that the thickness uniformity of the YF3 film prepared in this embodiment is 2%.

[0105] The YF3 film prepared in this example was characterized by XPS. Figure 3 As shown in the figure, it can be seen that the Y:F of the YF3 film prepared in this embodiment is 1:2.8, and there is no C impurity in the film layer.

[0106] The YF3 film prepared in this embodiment was subjected to a WER (wet etch rate) test, specifically: first the thickness of the film prepared in this embodiment was tested, then the film was placed in a prepared corrosion solution, the corrosion time was started, and then the film was taken out of the corrosion solution, the corrosion solution was cleaned and blown dry, and finally the thickness of the film was tested at this time, and the ratio of the difference between the two thicknesses and the time could be used to calculate the corrosion rate; the film prepared in this embodiment was divided into 5 parts according to the above method, and the corrosion was carried out for 0.5h, 1h, 1.5h, 2h, and 2.5h respectively, and the corrosion rate of each film was calculated, and then the average value was calculated; the WER test results show that the average corrosion rate of the YF3 film prepared in this embodiment is

[0107] Example 2

[0108] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0109] The wafer was sent into the reaction chamber, and then the chamber was evacuated. The pressure was adjusted at 0.5 mbar by a butterfly valve, and the temperature was controlled at 200 °C. Yttrium hexafluoroacetylacetonate was introduced, and the carrier gas flow rate was set to 200 sccm for 10 seconds, and then nitrogen was introduced for 30 seconds. Ozone was then introduced for 8 seconds with a flow rate of 1500 sccm, and finally nitrogen was introduced for 20 seconds. Thus, a sub-cycle of yttrium fluoride deposition was completed, and the deposition rate was During the deposition process, the source bottle of the yttrium hexafluoroacetylacetonate precursor is heated to 120°C, and the source pipeline is heated to 160°C; the oxygen source and the delivery pipeline are at room temperature and do not need to be heated;

[0110] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0111] Example 3

[0112] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0113] The wafer substrate is sent into the reaction chamber, and then the chamber is evacuated, the pressure is adjusted to 1mbar by a butterfly valve, and the temperature is controlled to 250℃; yttrium tris(thd)3 is introduced for 10s, the carrier gas flow rate is 100sccm, and then argon is introduced for 30s to purge the residual chemical source; then ozone is introduced for 10s, the carrier gas flow rate is 600sccm, and then argon is introduced for 30s to purge the residual chemical source; then hexafluoroacetylacetone Hhfac is introduced for 10s, the carrier gas flow rate is 200sccm, and then argon is introduced for 30s to purge; finally, ozone is introduced for 10s, the carrier gas flow rate is 600sccm, and then argon is introduced for 30s to purge, thereby completing the deposition of one sub-cycle of yttrium fluoride; during the deposition process, the Y(thd)3 source bottle is heated to 150℃, and the source pipeline is heated to 160℃; the fluorine source, oxygen source and delivery pipeline are at room temperature and do not need to be heated;

[0114] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0115] Example 4

[0116] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0117] The wafer substrate is sent into the reaction chamber, and then the chamber is evacuated, the pressure is adjusted to 6mbar by a butterfly valve, and the temperature is controlled to 400℃; yttrium tris(thd)3 is introduced for 15s, the carrier gas flow rate is 300sccm, and then argon is introduced for 50s to purge the residual chemical source; then ozone is introduced for 10s, the carrier gas flow rate is 500sccm, and then argon is introduced for 20s to purge the residual chemical source; then hexafluoroacetylacetone Hhfac is introduced for 15s, the carrier gas flow rate is 300sccm, and then argon is introduced for 30s to purge; finally, ozone is introduced for 10s, the carrier gas flow rate is 600sccm, and then argon is introduced for 20s to purge, thereby completing the deposition of one sub-cycle of yttrium fluoride; during the deposition process, the Y(thd)3 source bottle is heated to 170℃, and the source pipeline is heated to 200℃; the fluorine source, oxygen source and delivery pipeline are at room temperature and do not need to be heated;

[0118] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0119] Example 5

[0120] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0121] The wafer substrate is sent into the reaction chamber, and then the chamber is evacuated, the pressure is adjusted to 1mbar by a butterfly valve, and the temperature is controlled to 250℃; hexafluoroacetylacetone Hhfac is introduced for 10s, the carrier gas flow rate is 100sccm, and then argon is introduced for 30s to purge the residual chemical source; then ozone is introduced for 10s, the carrier gas flow rate is 600sccm, and then argon is introduced for 30s to purge the residual chemical source; then yttrium tris(thd)3 is introduced for 10s, the carrier gas flow rate is 200sccm, and then argon is introduced for 30s to purge; finally, ozone is introduced for 10s, the carrier gas flow rate is 600sccm, and then argon is introduced for 30s to purge, thereby completing the deposition of one sub-cycle of yttrium fluoride; during the deposition process, the Y(thd)3 source bottle is heated to 150℃, and the source pipeline is heated to 160℃; the fluorine source, oxygen source and delivery pipeline are at room temperature and do not need to be heated;

[0122] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0123] Example 6

[0124] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0125] The wafer substrate is sent into the reaction chamber, and then the chamber is evacuated, the pressure is adjusted to 6mbar by a butterfly valve, and the temperature is controlled to 400℃; hexafluoroacetylacetone Hhfac is introduced for 15s, the carrier gas flow rate is 300sccm, and then argon is introduced for 50s to purge the residual chemical source; then ozone is introduced for 10s, the carrier gas flow rate is 500sccm, and then argon is introduced for 20s to purge the residual chemical source; then yttrium tris(thd)3 is introduced for 15s, the carrier gas flow rate is 300sccm, and then argon is introduced for 30s to purge; finally, ozone is introduced for 10s, the carrier gas flow rate is 600sccm, and then argon is introduced for 20s to purge, thereby completing the deposition of one sub-cycle of yttrium fluoride; during the deposition process, the Y(thd)3 source bottle is heated to 170℃, and the source pipeline is heated to 200℃; the fluorine source, oxygen source and delivery pipeline are at room temperature and do not need to be heated;

[0126] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0127] Comparative Example 1

[0128] The wafer was sent into the reaction chamber, and then the chamber was evacuated. The pressure was adjusted to 1 mbar by a butterfly valve, and the temperature was controlled at 300 °C. Yttrium tris(dioxadione) acid Y(thd)3 was introduced, and the carrier gas flow rate was set to 300 sccm for 5 seconds, and then nitrogen was introduced for 15 seconds. Titanium tetrafluoride TiF4 was then introduced for 2 seconds with a flow rate of 1000 sccm, and finally nitrogen was introduced for 10 seconds. Thus, a sub-cycle of yttrium fluoride deposition was completed, and the deposition rate was During the deposition process, the source bottle of yttrium tris-diketonate is heated to 150°C, and the source pipeline is heated to 160°C; the source bottle of titanium tetrafluoride is heated to 170°C, and the source pipeline is heated to 180°C;

[0129] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0130] By comparison, it can be seen that in the above-mentioned process of preparing YF3 thin film, since titanium tetrafluoride is corrosive, the reaction chamber and pipelines need to be treated with anti-corrosion during deposition, while the parts with poor corrosion resistance and the substrate are still corroded, affecting the uniformity of the film layer; and the source bottle of titanium tetrafluoride is also heated, which increases the requirements and cost of the preparation equipment.

[0131] Comparative Example 2

[0132] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0133] The wafer was sent into the reaction chamber, and then the chamber was evacuated. The pressure was adjusted to 1 mbar by a butterfly valve, and the temperature was controlled at 300 °C. Yttrium hexafluoroacetylacetonate was introduced, and the carrier gas flow rate was set to 50 sccm for 5 seconds, and then nitrogen was introduced for 2 seconds. Ozone was then introduced for 2 seconds with a flow rate of 1000 sccm, and finally nitrogen was introduced for 10 seconds. Thus, a sub-cycle of yttrium fluoride deposition was completed, and the deposition rate was During the deposition process, the source bottle of the yttrium hexafluoroacetylacetonate precursor is heated to 100°C, and the source pipeline is heated to 120°C; the oxygen source and the delivery pipeline are at room temperature and do not need to be heated;

[0134] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0135] The experimental results show that the thickness uniformity of the YF3 film prepared in this comparative example is 6%.

[0136] Compared with the embodiment, during the preparation process of this comparative example, the amount of yttrium hexafluoroacetylacetonate introduced is too small and the purge time is short, so some areas do not evenly adsorb or deposit the atomic layer of yttrium hexafluoroacetylacetonate before the next layer grows, which affects the uniformity of the YF3 film and makes the uniformity of the YF3 film low.

[0137] Comparative Example 3

[0138] A YF3 film with a thickness of 30 nm is deposited on the surface of a silicon wafer (silicon-based wafer). The specific preparation method is as follows:

[0139] The wafer was sent into the reaction chamber, and then the chamber was evacuated. The pressure was adjusted at 1 mbar by a butterfly valve, and the temperature was controlled at 300 °C. Yttrium hexafluoroacetylacetonate was introduced, and the carrier gas flow rate was set to 800 sccm for 5 seconds, and then nitrogen was introduced for 15 seconds. Ozone was then introduced for 2 seconds with a flow rate of 1000 sccm, and finally nitrogen was introduced for 10 seconds. Thus, a sub-cycle of yttrium fluoride deposition was completed, and the deposition rate was During the deposition process, the source bottle of the yttrium hexafluoroacetylacetonate precursor is heated to 100°C, and the source pipeline is heated to 120°C; the oxygen source and the delivery pipeline are at room temperature and do not need to be heated;

[0140] The above steps were repeated 600 times to obtain a 30 nm YF3 film.

[0141] The experimental results show that the thickness uniformity of the YF3 film prepared in this comparative example is 9%.

[0142] Compared with the embodiment, during the preparation process of this comparative example, the amount of yttrium hexafluoroacetylacetonate introduced was too much and the purging time was too short, so part of the atomic layer of yttrium hexafluoroacetylacetonate was not fully purged before the deposition of the next atomic layer, which affected the uniformity of the YF3 film and made the uniformity of the YF3 film low.

[0143] In the process of preparing yttrium fluoride film in the above-mentioned embodiments of the present application, precursors and oxygen sources of two paths are used as reactants, and no toxic fluorine-containing gas is used, thereby ensuring the safety of yttrium fluoride film deposition; the yttrium fluoride film is prepared by atomic layer deposition, so that the film thickness is uniform and has strong corrosion resistance; further, the yttrium fluoride film prepared by the present application has a slow reduction or decrease rate of the film thickness in a corrosive environment, and has good structural stability. Experimental results show that the thickness of the yttrium fluoride film is reduced by only 0.05% after 1 hour in a corrosive environment. In the process of preparing yttrium fluoride film in the above-mentioned comparative example 1, toxic fluorine source titanium tetrafluoride is used, which needs to be heated, and the pipeline and reaction chamber need to be treated with corrosion protection. Even so, there is still a risk of corrosion, thereby increasing the requirements and cost of the preparation equipment; in the process of preparing yttrium fluoride film in the above-mentioned comparative example 2 and comparative example 3, too much or too little amount of precursor introduced, too short or too long inert gas purging time will affect the thickness uniformity of the yttrium fluoride film.

[0144] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0145] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing an yttrium fluoride thin film, comprising the following steps: S1) placing a substrate in an atomic layer deposition device, introducing precursors containing both yttrium and fluorine, and forming a film layer on the surface of the substrate after reaction; and purging the film layer; S2) introducing an oxygen source into the atomic layer deposition device to react with the film layer, and then purging again to obtain an yttrium fluoride film.

2. The preparation method according to claim 1, characterized in that: Step S2) also includes: Taking step S1) and step S2) as a preparation cycle, repeating the preparation cycle n times, where n≥1; And / or, in step S1), before introducing the precursor containing both yttrium and fluorine, the method further comprises: adjusting the temperature of the atomic layer deposition device to 200-500° C. and the pressure to 0.2-1.0 mbar; And / or, in step S1), the flow rate of the precursor containing both yttrium and fluorine into the atomic layer deposition device is 100-500sccm, and the introduction time is 1-15s; the heating temperature of the source bottle of the precursor containing both yttrium and fluorine is 80-120°C, and the heating temperature of the source pipeline is 90-160°C.

3. The preparation method according to claim 1, characterized in that: The precursor containing both yttrium and fluorine includes yttrium hexafluoroacetylacetonate, and the oxygen source includes ozone or oxygen plasma.

4. The preparation method according to claim 1, characterized in that: In step S2), the oxygen source is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm for a time period of 1 to 15 s; And / or, in step S1), the gas used for purging is nitrogen or argon, and the purging time is 5 to 50 seconds; in step S2), the gas used for re-purging is nitrogen or argon, and the purging time is 5 to 50 seconds.

5. A method for preparing an yttrium fluoride thin film, comprising the following steps: S1) placing a substrate in an atomic layer deposition device, introducing a first precursor, and forming a film layer on the surface of the substrate after reaction; and performing a first purge on the film layer; S2) introducing an oxygen source into the atomic layer deposition device to react with the film layer, and performing a second purge after the reaction; S3) introducing a second precursor into the atomic layer deposition device, reacting with the film layer obtained by the reaction in step S2), and then performing a third purge; S4) introducing an oxygen source into the atomic layer deposition device to react with the film layer obtained by the reaction in step S3) and then performing a fourth purge to obtain an yttrium fluoride film; The first precursor is selected from a yttrium-containing precursor or a fluorine-containing precursor, and correspondingly, the second precursor is selected from a fluorine-containing precursor or a yttrium-containing precursor.

6. The preparation method according to claim 5, characterized in that: Step S4) also includes: Taking step S1), step S2), step S3) and step S4) as a preparation cycle, repeating the preparation cycle n times, where n≥1; And / or, in step S1), before the first precursor is introduced, the method further comprises: adjusting the temperature of the atomic layer deposition device to 200-400° C. and the pressure to 0.2-10 mbar; And / or, the flow rate of the fluorine-containing precursor or the yttrium-containing precursor into the atomic layer deposition device is independently 100-500sccm, and the introduction time is independently 1-15s; the heating temperature of the source bottle of the yttrium-containing precursor is 120-170°C, and the heating temperature of the source pipeline is 150-200°C.

7. The preparation method according to claim 5, characterized in that: The yttrium-containing precursor includes yttrium trisdiketonate, the fluorine-containing precursor includes hexafluoroacetylacetone, and the oxygen source includes ozone or oxygen plasma.

8. The preparation method according to claim 5, characterized in that: In step S2), the oxygen source is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s; in step S4), the oxygen source is introduced into the atomic layer deposition device at a flow rate of 500 to 1500 sccm, and the introduction time is 1 to 15 s; And / or, in step S1), the gas used for the first purge is argon or nitrogen, and the time of the first purge is 5 to 50 s; in step S2), the gas used for the second purge is argon or nitrogen, and the time of the second purge is 5 to 50 s; in step S3), the gas used for the third purge is argon or nitrogen, and the time of the third purge is 5 to 50 s; in step S4), the gas used for the fourth purge is argon or nitrogen, and the time of the fourth purge is 5 to 50 s.

9. The preparation method according to any one of claims 1 to 8, characterized in that: The substrate is a hydroxylation-treated substrate.

10. An yttrium fluoride thin film prepared by the preparation method according to any one of claims 1 to 9.

11. A reaction chamber, comprising a structural component, characterized in that: A yttrium fluoride thin film is formed on the surface of the structural component, and the yttrium fluoride thin film is the yttrium fluoride thin film prepared by the preparation method according to any one of claims 1 to 9 or the yttrium fluoride thin film according to claim 10.

12. The reaction chamber according to claim 11, characterized in that: The structural component is a spray structure.

13. Application of yttrium fluoride film as an anti-corrosion coating on the surface of a structural component, wherein the yttrium fluoride film is the yttrium fluoride film prepared by the preparation method described in any one of claims 1 to 9 or the yttrium fluoride film described in claim 10.

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