Preparation method of fluorine-doped tin oxide film

Abstract

The invention provides a preparation method of a fluorine-doped tin oxide film. The preparation method comprises the following steps: placing a substrate in a deposition device; and carrying out at least one deposition treatment, wherein each deposition treatment independently comprises at least one tin oxide film sub-deposition treatment and at least one fluoride sub-deposition treatment. By changing the deposition treatment times, the tin oxide film sub-deposition times and the fluoride sub-deposition treatment times, the thickness of the fluorine-doped tin oxide film can be accurately regulated and controlled, the uniformity of the film is good, and the thickness difference is small.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a method for preparing a fluorine-doped tin oxide thin film. Background Art

[0002] Tin oxide is a wide bandgap oxide semiconductor that is transparent to visible light, with a bandgap of 3.7-4.0 eV and a regular tetrahedral rutile structure. After being doped with fluorine, SnO2:F thin films have been widely used in solar cells, electrothermal materials, transparent electrodes, and gas-sensitive materials due to their advantages such as good transmittance to visible light, large ultraviolet absorption coefficient, low resistivity, stable chemical properties, and strong acid and alkali resistance at room temperature. Currently, there are several methods for preparing fluorine-doped tin oxide thin films, including vapor deposition, sputtering, thermal evaporation, and sol-gel methods. However, these preparation methods cannot accurately control the thickness of fluorine-doped tin oxide thin films, and there are also differences in the uniformity and thickness of the film layer, which cannot meet the requirements of different working conditions. Summary of the invention

[0003] In view of the above technical problems, the present application provides a method for preparing a fluorine-doped tin oxide thin film. By changing the number of deposition treatments, the number of tin oxide film sub-depositions and the number of fluoride sub-deposition treatments, the thickness of the fluorine-doped tin oxide thin film can be precisely controlled, and the film has good uniformity and small thickness differences.

[0004] The first technical solution adopted in the present application is: to provide a method for preparing a fluorine-doped tin oxide thin film, comprising the following steps:

[0005] placing a substrate in a deposition apparatus;

[0006] At least one deposition process is performed, and each deposition process independently comprises at least one tin oxide film sub-deposition process and at least one fluoride sub-deposition process.

[0007] In some embodiments, the deposition apparatus comprises an atomic layer deposition apparatus.

[0008] In some embodiments, the tin oxide thin film sub-deposition process includes:

[0009] A tin source is introduced into the atomic layer deposition device, followed by a first purge gas;

[0010] A first oxygen source is introduced into the atomic layer deposition device, followed by a second purge gas, to complete the deposition of a tin oxide thin film on the substrate;

[0011] In some embodiments, the fluoride sub-deposition process includes:

[0012] A fluorine source is introduced into the atomic layer deposition device, followed by a third purge gas;

[0013] After the second oxygen source is introduced into the atomic layer deposition device, the fourth purge gas is introduced to complete the fluoride sub-deposition process on the tin oxide film.

[0014] In some embodiments, the number of deposition processes is M, the number of tin oxide film sub-deposition processes is m, and the number of fluoride sub-deposition processes is n; wherein M is greater than or equal to 1, m is greater than or equal to 1, n is greater than or equal to 0, and in the M deposition processes, at least one n is greater than 0.

[0015] In some embodiments, the relationship between the number m of the tin oxide film sub-deposition process and the number n of the fluoride film sub-deposition process is m:n=1-200:1.

[0016] In some embodiments, the tin source includes one or more of tetrakis(dimethylamino)tin (Sn(NMe2)4), tetrakis(methylethylamino)tin (Sn(NEtMe)4), and bis(acetylacetonate)tin (Sn(acac)2).

[0017] In some embodiments, the fluorine source includes hexafluoroacetylacetone.

[0018] In some embodiments, the first oxygen source includes one or more of ozone, H2O, and oxygen plasma, and the second oxygen source includes ozone.

[0019] In some embodiments, the first purge gas, the second purge gas, the third purge gas, and the fourth purge gas each independently include one or more of nitrogen, argon, and helium.

[0020] In some embodiments, the deposition process is performed at a temperature of 100° C. to 400° C. and a pressure of 0.2 mbar to 10 mbar.

[0021] In some embodiments, the temperature of the tin source is 50°C to 80°C, and the temperatures of the fluorine source, the first oxygen source, and the second oxygen source are each independently 0°C to 40°C.

[0022] In some embodiments, the pulse time of the tin source, the fluorine source, the first oxygen source, and the second oxygen source are each independently 0.5 s to 30 s, and the flow rates are each independently 100 sccm to 2000 sccm.

[0023] In some embodiments, the purge time of the first purge gas, the second purge gas, the third purge gas, and the fourth purge gas are each independently 3 seconds to 300 seconds, and the flow rates are each independently 200 sccm to 2000 sccm.

[0024] The second technical solution adopted in the present application is to provide a fluorine-doped tin oxide thin film, which is prepared by the preparation method of the fluorine-doped tin oxide thin film as described above.

[0025] Different from the prior art, the beneficial effect of the preparation method of fluorine-doped tin oxide film provided by the present application is that the thickness of the fluorine-doped tin oxide film can be precisely controlled by changing the number of deposition treatments, the number of tin oxide film sub-depositions and the number of fluoride sub-deposition treatments, and the prepared film has good uniformity and small thickness difference.

[0026] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above content and other purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0028] Figure 1 Schematic diagram of the preparation process of fluorine-doped tin oxide thin films according to some embodiments of the present application. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The terms "first", "second", "third" in this application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", "third" can expressly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the embodiments of this application, all directional indications (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the steps or units listed, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0031] The "range" disclosed in the present application is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 60 to 120 and 80 to 110 is listed for a particular parameter, it is understood that a range of 60 to 110 and 80 to 120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following ranges can all be expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4 and 2 to 5. In the present application, unless otherwise specified, the numerical range "a to b" represents an abbreviation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0032] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0034] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0035] refer to Figure 1 The present application provides a method for preparing a fluorine-doped tin oxide thin film, comprising the following steps:

[0036] placing a substrate in a deposition apparatus;

[0037] At least one deposition process is performed, and each deposition process independently comprises at least one tin oxide film sub-deposition process and at least one fluoride sub-deposition process.

[0038] In the technical solution of the embodiment of the present application, by changing the number of deposition treatments, the number of tin oxide film sub-depositions and the number of fluoride sub-deposition treatments, the thickness of the fluorine-doped tin oxide film can be accurately controlled, and the prepared film has good uniformity and small thickness difference.

[0039] In some embodiments, the deposition apparatus comprises an atomic layer deposition apparatus.

[0040] In the technical solution of the embodiment of the present application, the thickness of the fluorine-doped tin oxide film prepared by atomic layer deposition technology can be precisely controlled and has excellent uniformity.

[0041] In some embodiments, the tin oxide thin film sub-deposition process includes:

[0042] A tin source is introduced into the atomic layer deposition device, followed by a first purge gas;

[0043] A first oxygen source is introduced into the atomic layer deposition device, followed by a second purge gas, to complete the deposition of a tin oxide thin film on the substrate;

[0044] In some embodiments, the fluoride sub-deposition process includes:

[0045] A fluorine source is introduced into the atomic layer deposition device, followed by a third purge gas;

[0046] After the second oxygen source is introduced into the atomic layer deposition device, the fourth purge gas is introduced to complete fluorine doping on the tin oxide film.

[0047] In some embodiments, the number of deposition processes is M, the number of tin oxide film sub-deposition processes is m, and the number of fluoride sub-deposition processes is n; wherein M is greater than or equal to 1, m is greater than or equal to 1, n is greater than or equal to 0, and in the M deposition processes, at least one n is greater than 0.

[0048] In the technical solution of the embodiment of the present application, by changing the number of deposition processes to M, the number of tin oxide film sub-deposition processes to m, and the number of fluoride sub-deposition processes to n, the thickness of the fluorine-doped tin oxide film can be accurately controlled. M can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, etc., or a range consisting of any two of the above values, such as 1 to 10, 5 to 50, 40 to 100, etc. m can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, 200, etc., or a range consisting of any two of the above values, such as 1 to 10, 5 to 50, 40 to 200, etc. n can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, etc., or can be a range consisting of any two of the above values, for example, 0-10, 5-50, 40-100, etc.

[0049] In some embodiments, the relationship between the number m of the tin oxide film sub-deposition process and the number n of the fluoride film sub-deposition process is m:n=1-200:1.

[0050] In the technical solution of the embodiment of the present application, the ratio of the number of times m of the tin oxide film sub-deposition treatment to the number of times n of the fluoride sub-deposition treatment is within the above range. By adjusting the ratio of m to n, the thickness of the fluorine-doped tin oxide film can be precisely controlled. The ratio of m to n can be 1:1, 2:1, 3:1, 4:1, 5:1, 8:1, 10:1, 15:1, 20:1, 25:1, 30:1, 40:1, 50:1, 60:1, 80:1, 100:1, 150:1, 200:1, etc., or it can be a range consisting of any two of the above values, for example, 1 to 30:1, 20 to 100:1, 80 to 200:1, etc.

[0051] In some embodiments, the tin source includes one or more of tetrakis(dimethylamino)tin (Sn(NMe2)4), tetrakis(methylethylamino)tin (Sn(NEtMe)4), and bis(acetylacetonate)tin (Sn(acac)2).

[0052] In the technical solution of the embodiment of the present application, the above-mentioned tin source is used, tetrakis(dimethylamino)tin (Sn(NMe2)4), tetrakis(methylethylamino)tin (Sn(NEtMe)4), and bis(acetylacetonate)tin (Sn(acac)2) are combined with the substrate through chemical adsorption to provide a tin precursor for the tin oxide thin film deposition process.

[0053] In some embodiments, the fluorine source includes hexafluoroacetylacetone.

[0054] In the technical solution of the embodiment of the present application, the above-mentioned fluorine source is used. Hexafluoroacetylacetone contains six fluorine atoms. The CF bond makes hexafluoroacetylacetone have high chemical stability and thermal stability, and it is not easy to decompose or deteriorate. After the fluorine source containing hexafluoroacetylacetone is introduced into the atomic layer deposition equipment, the fluorine source is combined with the tin oxide film on the substrate through physical adsorption, providing a fluorine precursor for the fluoride sub-deposition treatment.

[0055] In some embodiments, the first oxygen source includes one or more of ozone, H2O, and oxygen plasma, and the second oxygen source includes ozone.

[0056] In the technical solution of the embodiment of the present application, the above-mentioned first oxygen source is used, and ozone, H2O, and oxygen plasma can react chemically with the tin precursor adsorbed on the substrate to generate tin oxide. The above-mentioned second oxygen source is used, and ozone can desorb the fluorine precursor ligand adsorbed on the tin oxide film, and the F- desorbed from the fluorine precursor ligand partially replaces the -OH on the substrate to complete fluorine doping.

[0057] In some embodiments, the first purge gas, the second purge gas, the third purge gas, and the fourth purge gas each independently include one or more of nitrogen, argon, and helium.

[0058] In the technical solution of the embodiment of the present application, the first purge gas, the second purge gas, the third purge gas, the fourth purge gas, nitrogen, argon, and helium are used as purge gases to purge away excess precursors and excess reaction by-products.

[0059] In some embodiments, the deposition process is performed at a temperature of 100° C. to 400° C. and a pressure of 0.2 mbar to 10 mbar.

[0060] In the technical solution of the embodiment of the present application, the temperature and pressure of the deposition process are within the above range, which can accelerate the chemical reaction of the precursor on the substrate surface, improve the deposition efficiency, reduce the generation of by-products, and form a thin film with good uniformity and small thickness difference. The temperature of the deposition process can be 100°C, 101°C, 105°C, 110°C, 120°C, 150°C, 200°C, 250°C, 300°C, 350°C, 400°C, etc., or it can be a range composed of any two of the above values, for example, 100°C to 200°C, 150°C to 350°C, 300 to 400°C, etc. The pressure of the deposition process can be 0.2mbar, 0.3mbar, 0.5mbar, 0.8mbar, 1mbar, 2mbar, 3mbar, 4mbar, 5mbar, 6mbar, 7mbar, 8mbar, 9mbar, 10mbar, etc., or it can be a range consisting of any two of the above values, for example, 0.2mbar~6mbar, 5mbar~9mbar, 8mbar~10mbar, etc.

[0061] In some embodiments, the temperature of the tin source is 50°C to 80°C, and the temperatures of the fluorine source, the first oxygen source, and the second oxygen source are each independently 0°C to 40°C.

[0062] In the technical solution of the embodiment of the present application, the temperature of the tin source can be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, or a range consisting of any two of the above values, for example, 50°C to 60°C, 55°C to 75°C, 70 to 80°C, etc. The temperatures of the fluorine source, the first oxygen source, and the second oxygen source can be 0°C, 1°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, or a range consisting of any two of the above values, for example, 0°C to 30°C, 25°C to 35°C, 30 to 40°C, etc.

[0063] In some embodiments, the pulse time of the tin source, the fluorine source, the first oxygen source, and the second oxygen source are each independently 0.5 s to 30 s, and the flow rates are each independently 100 sccm to 2000 sccm.

[0064] In the technical solution of the embodiment of the present application, the pulse time and flow rate of the tin source are within the above range to ensure that the tin precursor is fully chemically adsorbed on the surface of the substrate, providing a good basis for subsequent chemical reactions, and avoiding excessive unabsorbed tin precursor residues and side reactions caused by excessive tin precursors. The pulse time and flow rate of the fluorine source are within the above range to ensure that the fluorine precursor is fully physically adsorbed on the surface of the tin oxide film, providing a good basis for subsequent chemical reactions, and avoiding excessive unabsorbed fluorine precursor residues and side reactions caused by excessive fluorine precursors. The pulse time and flow rate of the first oxygen source are within the above range to ensure that the first oxygen source and the tin precursor adsorbed on the substrate react fully to avoid side reactions caused by excessive first oxygen source. The pulse time and flow rate of the second oxygen source are within the above range to ensure that the second oxygen source fully desorbs the fluorine precursor ligands adsorbed on the tin oxide film to avoid side reactions caused by excessive second oxygen source. The pulse time of the tin source, the fluorine source, the first oxygen source and the second oxygen source can be 0.5s, 0.6s, 0.8s, 1s, 1.5s, 2s, 3s, 4s, 5s, 6s, 7s, 8s, 9s, 10s, 20s, 25s, 30s, etc., or it can be a range consisting of any two of the above values, for example, 0.5s~5s, 2.5s~9s, 8s~30s, etc. The flow rates of the tin source, the fluorine source, the first oxygen source and the second oxygen source may be 100 sccm, 101 sccm, 105 sccm, 110 sccm, 150 sccm, 200 sccm, 300 sccm, 400 sccm, 500 sccm, 1000 sccm, 1200 sccm, 1500 sccm, 1800 sccm, 2000 sccm, etc., or may be a range consisting of any two of the above values, for example, 100 sccm to 800 sccm, 500 sccm to 1800 sccm, 1500 sccm to 2000 sccm, etc.

[0065] In some embodiments, the purge time of the first purge gas, the second purge gas, the third purge gas, and the fourth purge gas are each independently 3 seconds to 300 seconds, and the flow rates are each independently 200 sccm to 2000 sccm.

[0066] In the technical solution of the embodiment of the present application, the pulse time and flow rate of the first purge gas are within the above range to ensure that the excess tin precursor is fully purged. The pulse time and flow rate of the second purge gas are within the above range to ensure that the excess reaction byproducts after the first oxygen source reacts with the tin precursor adsorbed on the substrate to generate a tin oxide film are fully purged. The pulse time and flow rate of the third purge gas are within the above range to ensure that the excess fluorine precursor is fully purged. The pulse time and flow rate of the fourth purge gas are within the above range to ensure that the second oxygen source desorbs the fluorine precursor ligands adsorbed on the tin oxide film, and the F- desorbed from the fluorine precursor ligands partially replaces the -OH on the substrate, and the excess reaction byproducts are fully purged after fluorine doping is completed. The purge time of the first purge gas, the second purge gas, the third purge gas and the fourth purge gas can be 3s, 3.1s, 3.5s, 4s, 5s, 6s, 7s, 8s, 9s, 10s, 15s, 20s, 30s, 40s, 50s, 60s, 80s, 100s, 150s, 200s, 250s, 300s, etc., or it can be a range consisting of any two of the above values, for example, 3s~10s, 5s~200s, 150s~300s, etc. The flow rates of the first purge gas, the second purge gas, the third purge gas and the fourth purge gas may be 200 sccm, 201 sccm, 205 sccm, 210 sccm, 300 sccm, 400 sccm, 500 sccm, 1000 sccm, 1200 sccm, 1500 sccm, 1800 sccm, 2000 sccm, etc., or may be a range consisting of any two of the above values, for example, 200 sccm to 800 sccm, 500 sccm to 1800 sccm, 1500 sccm to 2000 sccm, etc.

[0067] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

[0068] The features and performance of the present application are further described in detail below in conjunction with the embodiments.

[0069] Embodiment 1:

[0070] a) placing the cleaned substrate in an atomic layer deposition device, controlling the device temperature to 150° C. and the pressure to 2 mbar;

[0071] b) performing 10 deposition processes, each deposition process independently comprising 30 tin oxide film sub-deposition processes and 1 fluoride sub-deposition process;

[0072] Tin oxide thin film sub-deposition process includes:

[0073] Tetrakis(dimethylamino)tin was introduced into the atomic layer deposition apparatus, followed by nitrogen purge; wherein the temperature of the tetrakis(dimethylamino)tin was 70°C, the pulse time was 1 s, and the flow rate was 500 sccm; the temperature of the nitrogen was room temperature, the purge time was 15 s, and the flow rate was 500 sccm.

[0074] After ozone is introduced into the atomic layer deposition device, nitrogen is introduced for purging to complete the deposition of tin oxide thin film on the substrate; wherein, the temperature of ozone is room temperature, the pulse time is 2s, and the flow rate is 500sccm; the temperature of nitrogen is room temperature, the purge time is 15s, and the flow rate is 500sccm.

[0075] Fluoride sub-deposition treatment includes:

[0076] Hexafluoroacetylacetone was introduced into the atomic layer deposition device, and then nitrogen was introduced for purging; wherein, the temperature of the hexafluoroacetylacetone was room temperature, the pulse time was 1 s, and the flow rate was 500 sccm; the temperature of the nitrogen was room temperature, the purge time was 15 s, and the flow rate was 500 sccm.

[0077] Ozone was introduced into the atomic layer deposition device and then nitrogen was introduced for purging to complete fluorine doping on the tin oxide film; wherein, the temperature of the ozone was room temperature, the pulse time was 2s, and the flow rate was 500sccm; the temperature of the nitrogen was room temperature, the purge time was 15s, and the flow rate was 500sccm.

[0078] XPS was used to determine the composition and content of elements in the fluorine-doped tin oxide film, and the results are shown in Table 1. From the characterization data in Table 1, it can be seen that the fluorine-doped tin oxide film was prepared by the above-mentioned atomic layer deposition process.

[0079] Table 1

[0080]

[0081] Embodiment 2:

[0082] Similar to Example 1, except that:

[0083] The tetrakis(dimethylamino)tin in step (b) of Example 1 was adjusted to tetrakis(methylethylamino)tin.

[0084] Embodiment 3:

[0085] Similar to Example 1, except that:

[0086] The ozone used in the tin oxide film sub-deposition treatment in step (b) of Example 1 was adjusted to H2O.

[0087] Embodiment 4:

[0088] Similar to Example 1, except that:

[0089] The 10 deposition processes in step (b) of Example 1 were adjusted to 3 deposition processes.

[0090] Embodiment 5:

[0091] Similar to Example 1, except that:

[0092] The 10 deposition processes in step (b) of Example 1 were adjusted to 100 deposition processes.

[0093] Embodiment 6:

[0094] Similar to Example 1, except that:

[0095] The 30 times of tin oxide thin film sub-deposition treatment in step (b) of Example 5 was adjusted to 90 times of tin oxide thin film sub-deposition treatment, and the 1 time of fluoride sub-deposition treatment was adjusted to 3 times of fluoride sub-deposition treatment.

[0096] Embodiment 7:

[0097] Similar to Example 1, except that:

[0098] The 30 tin oxide thin film sub-deposition treatments in step (b) of Example 1 were adjusted to 3 tin oxide thin film sub-deposition treatments.

[0099] Embodiment 8:

[0100] Similar to Example 1, except that:

[0101] The 30 tin oxide thin film sub-deposition treatments in step (b) of Example 1 were adjusted to 200 tin oxide thin film sub-deposition treatments.

[0102] Embodiment 9:

[0103] Similar to Example 1, except that:

[0104] The one fluoride sub-deposition treatment in step (b) of Example 1 was adjusted to 10 fluoride sub-deposition treatments.

[0105] Embodiment 10:

[0106] Similar to Example 1, except that:

[0107] The one fluoride sub-deposition treatment in step (b) of Example 1 was adjusted to 30 fluoride sub-deposition treatments.

[0108] Comparative Example 1:

[0109] a) Target preparation: 99.99% pure SnO2 powder and 99% SnF2 powder were mixed at a weight ratio of 95:5 and heated at 2×10 6 After being pressed and formed under the conditions of 200 mbar and 120°C, it was sintered at 190°C in air to form SnO2:F target.

[0110] b) Place the cleaned substrate and SnO2 target into the RF magnetron sputtering instrument. Adjust the distance from the target to the substrate to 40 mm and the basic vacuum of the sputtering chamber to 4.0×10 -6 mbar, the sputtering gas argon pressure is 0.01 mbar, the sputtering bias is -50 V and the sputtering power is 100 W.

[0111] c) Start the RF magnetron sputtering instrument to perform sputtering coating. During the sputtering process, argon gas is ionized under the action of the electric field to produce Ar + Ion, Ar + The ions are accelerated to fly toward the cathode target, bombarding the target surface, causing atoms or molecules in the target to sputter out and deposit on the substrate surface to form a fluorine-doped tin oxide film.

[0112] The fluorine-doped tin oxide films 1 to 11 obtained in the above Examples 1 to 10 and Comparative Example 1 were tested to obtain Table 1.

[0113] Test method:

[0114] 1. Thickness test method: Take a measurement area on the fluorine-doped tin oxide film, divide the measurement area into a 7×7 grid, and use an ellipsometer to measure the thickness of these 49 points. Add the thickness values ​​of the 49 measurement points and divide them by 49 to get the average thickness.

[0115] 2. Thickness deviation test method: Calculate the thickness standard deviation using the 49 thickness data measured by the ellipsometer. The standard deviation formula is:

[0116]

[0117] σ: standard deviation;

[0118] N: the total number of data points measured;

[0119] t i : The thickness value of the i-th data point;

[0120] Mean: The average value of all data points.

[0121] 3. Thickness uniformity:

[0122]

[0123] uni%: thickness uniformity ratio;

[0124] σ: standard deviation;

[0125] Mean: The average value of all data points.

[0126]

[0127] It can be seen from Examples 1 to 10 that the thickness of the fluorine-doped tin oxide film can be precisely controlled by changing the number of deposition treatments, the number of tin oxide film sub-depositions, and the number of fluoride sub-depositions; the thickness uniformity of the film varies with thickness. However, in combination with Comparative Example 1, it can be seen that the uniformity of the fluorine-doped tin oxide film prepared in the present application is significantly improved and the thickness difference is small.

[0128] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for preparing a fluorine-doped tin oxide thin film, characterized in that: The following steps are involved: placing a substrate in a deposition apparatus; At least one deposition process is performed, and each deposition process independently comprises at least one tin oxide film sub-deposition process and at least one fluoride sub-deposition process.

2. The method for preparing a fluorine-doped tin oxide thin film according to claim 1, characterized in that: The deposition device includes an atomic layer deposition device.

3. The method for preparing a fluorine-doped tin oxide thin film according to claim 1, characterized in that: The tin oxide thin film sub-deposition process comprises: After introducing a tin source into the deposition device, a first purge gas is introduced; A first oxygen source is introduced into the deposition device, and then a second purge gas is introduced to complete the deposition of a tin oxide film on the substrate.

4. The method for preparing a fluorine-doped tin oxide thin film according to claim 1, characterized in that: The fluoride sub-deposition process comprises: introducing a fluorine source into the deposition device and then introducing a third purge gas; After the second oxygen source is introduced into the deposition device, a fourth purge gas is introduced to complete the fluoride sub-deposition process on the tin oxide film.

5. The method for preparing a fluorine-doped tin oxide thin film according to claim 1, characterized in that: The number of times of the deposition treatment is M, the number of times of the tin oxide film sub-deposition treatment is m, and the number of times of the fluoride sub-deposition treatment is n; Wherein, M is greater than or equal to 1, m is greater than or equal to 1, n is greater than or equal to 0, and in the M deposition processes, at least one n is greater than 0.

6. The method for preparing a fluorine-doped tin oxide thin film according to claim 5, characterized in that: The relationship between the number m of the tin oxide film sub-deposition process and the number n of the fluoride sub-deposition process is m:n=1-200:

1.

7. The method for preparing a fluorine-doped tin oxide thin film according to claim 3, characterized in that: The tin source includes one or more of tetrakis(dimethylamino)tin (Sn(NMe2)4), tetrakis(methylethylamino)tin (Sn(NEtMe)4), and bis(acetylacetonate)tin (Sn(acac)2).

8. The method for preparing a fluorine-doped tin oxide thin film according to claim 4, characterized in that: The fluorine source includes hexafluoroacetylacetone.

9. The method for preparing a fluorine-doped tin oxide thin film according to claim 3, characterized in that: The first oxygen source includes one or more of ozone, H2O, and oxygen plasma, and the first purge gas and the second purge gas each independently include one or more of nitrogen, argon, and helium.

10. The method for preparing a fluorine-doped tin oxide thin film according to claim 4, characterized in that: The second oxygen source includes ozone, and the third purge gas and the fourth purge gas each independently include one or more of nitrogen, argon, and helium.

11. The method for preparing a fluorine-doped tin oxide thin film according to claim 1, characterized in that: The temperature of the deposition process is 100° C. to 400° C., and the pressure is 0.2 mbar to 10 mbar.

12. The method for preparing a fluorine-doped tin oxide thin film according to claim 3, characterized in that: The temperature of the tin source is 50°C to 80°C, and the temperature of the first oxygen source is 0°C to 40°C.

13. The method for preparing a fluorine-doped tin oxide thin film according to claim 3, characterized in that: During a tin oxide thin film deposition process, the introduction time of the tin source and the first oxygen source is independently 0.5s to 30s, the purge time of the first purge gas and the second purge gas is independently 3s to 300s, and the flow rate is independently 200sccm to 2000sccm.

14. The method for preparing a fluorine-doped tin oxide thin film according to claim 4, characterized in that: The temperatures of the fluorine source and the second oxygen source are independently 0°C to 40°C.

15. The method for preparing a fluorine-doped tin oxide thin film according to claim 4, characterized in that: During a fluoride sub-deposition process, the introduction time of the fluorine source and the second oxygen source is independently 0.5s to 30s, and the flow rate is independently 100sccm to 2000sccm. The purge time of the third purge gas and the fourth purge gas is independently 3s to 300s, and the flow rate is independently 200sccm to 2000sccm.

16. A fluorine-doped tin oxide thin film, characterized in that: The fluorine-doped tin oxide thin film is prepared by the method for preparing a fluorine-doped tin oxide thin film according to any one of claims 1 to 15.

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