CN108385072B

CN108385072B - Transparent conductive film with single-layer structure and preparation method and application thereof

Info

Publication number: CN108385072B
Application number: CN201810048854.5A
Authority: CN
Inventors: 宋伟杰; 许君君; 李佳; 黄金华; 杨晔; 盛伟
Original assignee: Ningbo Institute of Material Technology and Engineering of CAS
Current assignee: Ningbo Institute of Material Technology and Engineering of CAS
Priority date: 2018-01-18
Filing date: 2018-01-18
Publication date: 2020-04-21
Anticipated expiration: 2038-01-18
Also published as: CN108385072A

Abstract

The invention discloses a transparent conductive film with a single-layer structure, a preparation method and application thereof, wherein the preparation comprises the following steps: loading the cleaned substrate into a vacuum chamber of a vacuum magnetron sputtering device, wherein the vacuum degree of the chamber is 1 × 10^‑4～7×10^‑4When the pressure is Pa, argon is filled, the total pressure is controlled to be 0.16Pa, the sputtering power of the target is adjusted to be 10-60W, then a sample baffle is opened, and the surface of the substrate is deposited by adopting a direct-current magnetron sputtering method to obtain the transparent conductive film; the transparent conductive film is composed of silver and a metal oxide. The invention prepares the transparent metal conductive film with lower thickness, continuity and better stability by directly sputtering the alloy target material consisting of silver and metal oxide or co-sputtering the silver and metal oxide target material so as to achieve the aims of reducing the structural complexity and reducing the material consumption.

Description

Transparent conductive film with single-layer structure and preparation method and application thereof

Technical Field

The invention relates to the field of preparation of transparent conductive films, in particular to a transparent conductive film with a single-layer structure and a preparation method and application thereof.

Background

Currently, transparent conductive films intended to replace ITO mainly include other doped semiconductors, conductive polymers, graphene, carbon nanotubes, and metals (including metal nanowires, metal grids, and ultra-thin metal films).

For example, patent publication No. US 005786094 a discloses an ultra-thin metallic transparent conductive film having environmental stability. The prepared ultrathin metal film has a single-layer structure and mainly comprises a glass substrate and a metal layer. The substrate is activated by previously irradiating the substrate with an ion beam, an electron beam, a laser beam, or a combination thereof, thereby obtaining a continuous ultra-thin metal layer at a lower thickness. The metal layer mainly adopts transition metals such as Ti, V, Cr, Mn, Co, Ni, Zr, Nb, Mo, Rh, Pd, Ag, Hf, Ta, W, Ir, Pt, Au, lanthanide series metal and actinide series metal. The ultrathin metal film has better stability in a 0.5 percent sodium chloride aqueous solution spraying experiment and a 0.1N hydrochloric acid soaking solution. However, this patent document requires a prior activation of the substrate to obtain a continuous ultra-thin metal layer at a lower thickness, and does not clearly illustrate the threshold thickness of the resulting ultra-thin metal film.

Patent document WO/2016/130717a1 discloses a method for producing a flexible ultrathin transparent conductive metal film that is scratch-resistant and has a smooth surface. The prepared ultrathin metal film has a multilayer structure, and mainly comprises a flexible transparent substrate and metal/metal oxide/metal oxide … … alternating layers from bottom to top, wherein the metal is mainly Ag, Cu, Al or a combination of the above, the thickness is 0.5-3nm, the metal oxide is mainly Ag, Cu, Al or an oxide formed after the combination of the above is exposed in the air for 1-60s, and the thickness is less than 0.05 nm. The threshold thickness of the ultra-thin metal film may be less than 2 nm. The patent document uses a metal oxide layer to block diffusion and aggregation of a bottom metal layer, and the obtained ultrathin metal film has a structure larger than two layers.

Patent document US 9012044B 2 discloses a transparent conductive film with good stability based on an ultra-thin metal layer. The transparent conductive film has a multilayer structure, and the main structure of the transparent conductive film comprises a substrate, a metal oxide layer, a polycrystalline seed layer, a conductive metal or alloy layer and a barrier layer on the top from bottom to top. The metal oxide layer is mainly SnO₂、ZnO、ZnSnO₃、Zn₂SnO₄、In₂O₃、Bi₂O₃ITO or their combination, and the polycrystalline seed layer mainly adopts ZnO and Al₂O₃Or a combination thereof, the conductive metal layer or alloy layer is mainly Ag, Au, Cu, Ni, Cr or a combination thereof, and the barrier layer is mainly a metal oxide layer or a polymer layer. This patent document uses a metal oxide as a wetting layer and the resulting transparent conductive film has a structure greater than two layers.

In these systems, the ultra-thin metal (< 10nm) transparent conductive thin film generally has a multilayer composite structure, and the composite structure is designed from the starting point of realizing the conversion from three-dimensional island shape to two-dimensional continuity of the growth mode of the metal thin film under a lower thickness by means of substrate surface modification, seed layer and the like, and from the starting point of adding a barrier layer or a protective layer on the top of the metal thin film, so that the metal thin film has better stability under various use conditions.

In recent years, with the research on the growth mechanism of the metal thin film and the mechanism of the performance degradation thereof under various conditions, it has become possible to obtain an ultra-thin metal thin film having a simple structure, a low threshold thickness, and good stability. At the same time, however, good stability is also required for the real application of ultra-thin Ag metal films in electronic devices. However, the existing methods for improving the stability of the Ag film are relatively single and lack systematic research on the stability of the Ag film. With the trend of smaller size and stronger function of electronic devices, the required current density of the electronic devices is gradually increased, and the surge current borne at the switching moment is also increased, which requires that the transparent conductive film has better stability under the impact of the surge current. However, there is currently little study on the stability of ultra-thin Ag films under surge current.

Disclosure of Invention

Aiming at the current situation that the existing ultrathin metal transparent conductive film mostly has a multilayer structure and simultaneously aiming at improving the anti-surge property of the transparent conductive film, the invention provides the transparent conductive film with a single-layer structure and a preparation method and application thereof.

The purpose of the invention is realized by the following technical scheme:

a method for preparing a transparent conductive film having a single-layer structure, comprising: loading the cleaned substrate into a vacuum chamber of a vacuum magnetron sputtering deviceThe vacuum degree of the chamber is 1 x 10^-4～7×10^-4When the pressure is Pa, argon is filled, the total pressure is controlled to be 0.16Pa, the sputtering power of the target is adjusted to be 10-60W, then a sample baffle is opened, and the surface of the substrate is deposited by adopting a magnetron sputtering method to obtain the transparent conductive film;

the transparent conductive film is composed of silver and a metal oxide.

Wherein the metal oxide is selected from CdO, ZnO and In₂O₃、SnO₂、MoO₃、ZrO₂、PdO、TiO₂And HfO₂At least one of (1).

Preferably, the atomic percentage of the metal oxide in the transparent conductive film is 1-20%. The metal oxide plays a role in increasing the metal nucleation density and blocking metal diffusion and aggregation, so that the ultrathin metal film which is continuous and flat at a lower thickness and has better stability can be obtained by direct sputtering.

Further preferably, the transparent conductive film is composed of Ag and CdO.

Preferably, the substrate is glass, PET, PEF or PC.

The substrate is sequentially ultrasonically cleaned by acetone, ethanol and deionized water, and dried N is used₂Blow-drying and then loading into a vacuum chamber.

The magnetron sputtering method adopts a direct sputtering alloy target or a co-sputtering silver and metal oxide target, wherein the alloy target consists of silver and metal oxide, and the atomic percentage of the metal oxide is 1-20%.

Preferably, the sputtering time of the target is 10-90 s, and the thickness of the film is regulated and controlled by controlling the sputtering time.

The invention also provides the transparent conductive film with the single-layer structure, which is prepared by the method, and the thickness of the transparent conductive film is 3-12 nm.

The invention also aims to provide application of the transparent conductive film with the single-layer structure in photoelectric devices. The transparent conductive film has good conductivity and high optical transmittance, and can be widely applied to various photoelectric devices, such as solar cells, image sensors, liquid crystal displays, organic electroluminescence (OLED) and touch screen panels.

Compared with the prior art, the invention has the following beneficial effects:

(1) the existing ultra-thin silver transparent conductive thin film is generally realized by a multilayer structure. The continuity of the silver film under the lower thickness is realized by surface modification or introduction of a seed crystal layer on the bottom layer; and a barrier layer or a protective layer is added on the top layer, so that the better stability of the silver film is realized. The multi-layer structure tends to increase cost and process complexity. The invention adopts the direct sputtering of the alloy target material consisting of metal and metal oxide or the co-sputtering of metal and metal oxide target material, and utilizes the metal oxide to increase the metal nucleation density and prevent the diffusion and aggregation of metal, thereby preparing the continuous transparent conductive film with lower thickness and better stability.

(2) The invention improves the heat stability and the damp-heat stability of the film and improves the anti-surge property of the film.

Drawings

FIG. 1(a) shows the transmittance of Ag-CdO films of different thicknesses; FIG. 1(b) is a graph showing sheet resistance of Ag-CdO films of different thicknesses;

FIG. 2(a) is a spectrum of Ag 3d in an Ag-CdO film; FIG. 2(b) shows the Cd 3d spectrum and O1 s spectrum in the Ag-CdO film;

FIG. 3(a) shows the early growth process of Ag-CdO films and pure Ag films; FIG. 3(b) is the average roughness of 2, 3, 5nm Ag-CdO films and pure Ag films; FIG. 3(c) shows diffraction peaks of 50nm Ag-CdO film and pure Ag film;

fig. 4(a) is a schematic diagram of an apparatus and pulse mode for testing surge-resistant characteristics; FIG. 4(b) is a graph of the average lifetimes of Ag-CdO films and pure Ag films at different current densities; FIG. 4(c) passing Current Density of 0.83MA/cm²The shape of a pure Ag film line area which fails after 5.5h of impulse current impact; FIG. 4(d) passing Current Density of 0.83MA/cm²The appearance of the Ag-CdO film which is not failed after being impacted by the pulse current for 5.5 hours;

FIG. 5(a) is a graph showing the sheet resistance of a pure Ag film and an Ag-CdO film after annealing at different temperaturesVariation (R)₀Is the initial sheet resistance, and R is the annealed sheet resistance); FIG. 5(b) shows the shapes of the pure Ag film and the Ag-CdO film after rapid thermal annealing at 200 ℃;

FIG. 6(a) is a transmittance change curve of the Ag-CdO film in a high accelerated aging test; FIG. 6(b) is a square resistance change curve of the Ag-CdO film in a high accelerated aging test.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is described in further detail below with reference to the accompanying drawings and examples, but it should not be understood that the scope of the above subject matter of the present invention is limited to the following examples, and all the technologies realized based on the above contents of the present invention belong to the scope of the present invention.

Example 1

(1) Using ultra-white glass with the thickness of 1mm as a transparent substrate, sequentially using acetone, ethanol and deionized water to ultrasonically clean the glass, and using dry N₂Drying, then immediately placing the dried product into a vacuum chamber of vacuum magnetron sputtering equipment, and starting vacuumizing;

(2) pumping the vacuum chamber to 7 × 10^-4Introducing 40sccm of high-purity argon as a deposition gas below Pa, and controlling the total pressure to be 0.16 Pa. Taking Ag-CdO alloy as a target material, wherein the atomic percent of CdO is 12.9%; and adjusting the sputtering power of the target material to be 40W, continuously sputtering for 15s by adopting a direct-current magnetron sputtering method, depositing the surface of the substrate, and taking out the sample after the film deposition is finished to obtain a glass/Ag-CdO sample, namely the transparent conductive film. In the preparation process, the substrate temperature is room temperature, and the substrate is kept rotating to ensure the uniformity of the film;

the thickness of the Ag-CdO film in the glass/Ag-CdO sample was 5.4nm as measured by an ellipsometer, the transmittance was 76% at a wavelength of 550nm (a wavelength to which human eyes are sensitive), and the sheet resistance was 54.2. omega./sq as measured by a four-probe.

Example 2

(1) Using ultra-white glass with the thickness of 1mm as a transparent substrate, sequentially using acetone, ethanol and deionized water to ultrasonically clean the glass, and using dry N₂Blow-drying, followed byImmediately putting the mixture into a vacuum chamber of vacuum magnetron sputtering equipment, and starting vacuumizing;

(2) pumping the vacuum chamber to 7 × 10^-4Introducing 40sccm of high-purity argon as a deposition gas below Pa, and controlling the total pressure to be 0.16 Pa. Co-sputtering is adopted, pure Ag and conductive ZnO are used as targets, the sputtering power of the pure Ag target is adjusted to be 40W, the sputtering power of the conductive ZnO target is 16W, the direct-current magnetron sputtering method is adopted for continuous sputtering for 18s, the surface of the substrate is deposited, a sample is taken out after the film deposition is finished, a glass/Ag-ZnO sample is obtained, and the atomic percent of ZnO in the obtained sample is 2.3%.

(3) Measuring the thickness of the Ag-ZnO film in the glass/Ag-ZnO sample by using an ellipsometer to be 6.7 nm; the optical fiber had a transmittance of 78% at a wavelength of 550nm (a wavelength sensitive to human eyes), and the sheet resistance was measured to be 20.4. omega./sq using a four-probe.

Example 3

(2) pumping the vacuum chamber to 7 × 10^-4Introducing 40sccm of high-purity argon as a deposition gas below Pa, and controlling the total pressure to be 0.16 Pa. Taking Ag-CdO alloy as a target material, wherein the atomic percent of CdO is 3.6%; and adjusting the sputtering power of the target material to be 40W, continuously sputtering for 1min by adopting a direct-current magnetron sputtering method, depositing the surface of the substrate, and taking out the sample after the film deposition is finished to obtain a glass/Ag-CdO sample, namely the transparent conductive film. In the preparation process, the substrate temperature is room temperature, and the substrate is kept rotating to ensure the uniformity of the film;

the thickness of the Ag-CdO film in the glass/Ag-CdO sample was measured to be 8.6nm using an ellipsometer, and the deposition rate was determined to be 0.14 nm/s.

Examples 4 to 7

The sputtering method and parameters of example 3 were used except that the sputtering time was changed to 21s, 36s, 50s, 64s and 79s, respectively, and Ag — CdO films with thicknesses of 3nm, 5nm, 7nm, 9nm and 11nm were sputtered on the substrate, respectively.

The thickness of the Ag-CdO film in the glass/Ag-CdO samples was calculated based on the calibrated deposition rate and subsequently confirmed by an ellipsometer.

The transmittance of the above Ag-CdO film was measured by an ellipsometer, and the measurement result is shown in fig. 1 (a); the sheet resistance of the above Ag-CdO film was measured using a four-point probe, and the measurement results are shown in FIG. 1 (b). The transmittance and the sheet resistance curve of the Ag-CdO film with different thicknesses are combined, the Ag-CdO film has a transmittance close to 80% at a wavelength of 550nm (a wavelength sensitive to human eyes) when the thickness is 5-7 nm, and the sheet resistance is less than 40 omega/sq, so that the Ag-CdO film can be used as a transparent conductive film.

The specific components of the Ag-CdO film are explored:

the sputtering method and parameters of example 3 were used except that the sputtering time was changed to 35min, and an Ag — CdO film having a thickness of 300nm was sputtered on the substrate.

The composition elements and chemical states of the Ag-CdO film are detected by XPS (X-ray Photoelectron Spectroscopy), and the test result is shown in FIG. 2, wherein FIG. 2(a) is a Ag 3d spectrum in the Ag-CdO film; FIG. 2(b) shows the Cd 3d spectrum and O1 s spectrum of the Ag-CdO film. It can be confirmed that the main components of the Ag — CdO thin film are Ag and CdO added thereto. The Ag content and the CdO content were 96.4 at% and 3.6 at% respectively, as determined by XPS.

The mechanism that the threshold thickness of the Ag-CdO film is lower than that of a pure Ag film is explored:

analysis of FIG. 1 shows that the Ag-CdO film has no obvious absorption peak in the transmission curve at the thickness of 5nm, and the sheet resistance is less than 40 Ω/sq at the time, which indicates that the threshold thickness of the Ag-CdO film is less than 5 nm. This threshold thickness is less than the 10nm threshold thickness for pure Ag mentioned in the literature.

In order to investigate the mechanism that the threshold thickness of the Ag-CdO thin film is lower than that of the pure Ag thin film, the sputtering method of example 3 was used to sputter an Ag-CdO thin film and a pure Ag thin film with thicknesses of 2, 3, and 5nm on a substrate by varying the sputtering time, respectively, to compare the growth processes of the Ag-CdO thin film and the pure Ag thin film before the continuation. Additionally, 50nm of Ag-CdO film and pure Ag film were sputtered to compare the grain sizes of the Ag-CdO film and the pure Ag film at the same thickness.

The surface morphologies of the 2, 3, and 5nm Ag-CdO films and the pure Ag films were observed by SEM (Scanning Electron Microscope) and AFM (atomic force Microscope), while the film average roughness was measured by AFM. Diffraction peaks of 50nm Ag-CdO film and pure Ag film were measured by XRD (X-Ray Diffraction), and the grain size was calculated by using the Sherrer's formula. The measurement results are shown in fig. 3, wherein fig. 3(a) shows the early growth process of Ag — CdO thin film and pure Ag thin film (the inset is AFM image corresponding to thickness); FIG. 3(b) is the average roughness of 2, 3, 5nm Ag-CdO films and pure Ag films; FIG. 3(c) shows diffraction peaks of a 50nm Ag-CdO film and a pure Ag film.

In combination with fig. 3(a), it is found that the surface morphologies of the Ag-CdO thin film and the pure Ag thin film are not significantly different at a thickness of 2nm, corresponding to the early stage of discrete nanocluster nucleation; when the thickness is 3nm, the addition of CdO ensures that the Ag-CdO film has a more compact surface appearance and the film particles are finer, which shows that the addition of CdO increases the nucleation density of the Ag-CdO film and simultaneously hinders the growth of Ag crystal grains and the aggregation of Ag particles; when the thickness is 5nm, the Ag-CdO film has a flat and smooth surface, while the pure Ag film forms more Ag nanoclusters due to the aggregation of Ag particles, resulting in the formation of a rough surface morphology. The average roughness curve of fig. 3(b) also verifies the above-described trend of change. In combination with the diffraction peak measured in fig. 3(c), the grain size of the 50nm Ag-CdO film calculated by the scherrer equation was 16nm, while the grain size of the Ag film was 32nm, further indicating that the addition of CdO effectively hindered the growth of Ag grains.

By combining the comparison and analysis, the mechanism that the threshold thickness of the Ag-CdO film is lower can be obtained: the CdO is taken as second phase particles in the target material, and Cd atoms and O atoms reach the surface of the substrate along with Ag atoms in the magnetron sputtering process and are adsorbed on the substrate together with the Ag atoms by means of electrostatic interaction. In the early nucleation process, the CdO is used as a heterogeneous core, and the nucleation site density of the Ag film is increased. During late growth, CdO no longer serves as a nucleation site. The continuously sputtered CdO particles are dispersed and distributed in the Ag film as a second phase, and play a role in pinning the grain boundary of Ag film grains, so that the surface diffusion and mass transmission of Ag are blocked, and the growth of the Ag grains is inhibited, so that the Ag-CdO film can continuously grow at a lower thickness and simultaneously form a compact and smooth surface appearance.

The stability of the Ag-CdO film and the pure Ag film is researched and compared:

in order to compare the surge resistance, thermal stability and wet-heat stability of the Ag-CdO thin film and the pure Ag thin film, the stability test was performed by sputtering the Ag-CdO thin film and the pure Ag thin film on the substrate with a thickness of 12nm by changing the sputtering time using the sputtering method of example 3.

a. Anti-surge property

As electronic devices are developed to have smaller size and stronger functions, the required current density is gradually increased, and the surge current born at the switching moment is also increased. This puts new demands on transparent conductive films used in electronic devices, i.e. better stability under surge current. The invention first explores the anti-surge property of the transparent conductive film, and the test result is shown in fig. 4, wherein fig. 4(a) is a schematic diagram of a test device and a pulse mode; FIG. 4(b) is a graph of the average lifetimes of Ag-CdO films and pure Ag films at different current densities; FIG. 4(c) passing Current Density of 0.83MA/cm²The shape of a pure Ag film line area which fails after 5.5h of impulse current impact; FIG. 4(d) passing Current Density of 0.83MA/cm²The appearance of the Ag-CdO film which does not lose efficacy after being impacted by the pulse current for 5.5 hours.

The schematic diagram of the apparatus and pulse mode under test is shown in fig. 4 (a). The method mainly comprises the steps that a direct-current power supply, an electronic load and a film to be tested form a power-on loop, the direct-current power supply is used for powering on a circuit, and the electronic load adjusts the mode of pulse current. The duty ratio of the adopted pulse current is 0.03, and one period is 10.3s, wherein the current in the circuit within 10s is 0A, and the current in the circuit within 0.3s is a constant value. And (3) continuously circulating pulse current is conducted on the film, and the stability of the film under the surge current is observed.

By the pair AThe g-CdO film and the pure Ag film are respectively electrified with the current density of 0.63MA/cm²、0.83MA/cm²、1.04MA/cm²And 1.25MA/cm²The service life of the Ag-CdO film and the pure Ag film under the pulse current is observed. The lifetime duration begins with the application of a pulsed current to the membrane and ends with the failure of the membrane causing the circuit to open. The experiment was repeated three times to take an average, and the result is shown in fig. 4(b), where the Ag — CdO film had a longer lifetime than the pure Ag film.

The failure mode of the film under the action of the pulse current is macroscopically represented by that a grain penetrating through a power-on section appears on the surface of the film, and the current is difficult to reach the other side from one side of the grain, so that the circuit is broken. The micro-morphology of the texture is shown as the aggregation of the film particles at that location. FIG. 4(c) passing Current Density of 0.83MA/cm²The shape of a pure Ag film line area which fails after 5.5h of impact of the pulse current. The surface appearance of the Ag-CdO film is not obviously changed under the same condition, and the passing current density of the graph of FIG. 4(d) is 0.83MA/cm²The appearance of the Ag-CdO film which does not lose efficacy after being impacted by the pulse current for 5.5 hours. The duty ratio of the 12nm Ag-CdO film is 0.03, and the current density is 0.63MA/cm²、0.83MA/cm²、1.04MA/cm²And 1.25MA/cm²Has a life of 62.3h, 26.6h, 2.9h and 1.6h on average in the rectangular pulse current mode. The addition of CdO ensures that the appearance of the Ag-CdO film is more compact, and the diffusion and aggregation of Ag particles are inhibited, so that the Ag-CdO film has longer service life.

b. Thermal stability

In order to research and compare the thermal stability of the Ag-CdO film and the pure Ag film, Rapid Thermal Annealing (RTA) treatment is carried out on the Ag-CdO film and the pure Ag film within the temperature range of 100-250 ℃, the annealing atmosphere is air, and the time is 10 min. The results are shown in FIG. 5, in which FIG. 5(a) shows the sheet resistance change (R) of the pure Ag film and the Ag-CdO film after annealing at different temperatures₀Is the initial sheet resistance, and R is the annealed sheet resistance); FIG. 5(b) shows the shapes of the pure Ag film and the Ag-CdO film after RTA at 200 ℃.

As shown in fig. 5(a), the resistance of the pure Ag film rapidly increases after 100 ℃, while the sheet resistance of the Ag — CdO film remains low at 250 ℃. Compared with the appearance of the pure Ag film and the Ag-CdO film after the RTA at the temperature of 200 ℃, the pure Ag film generates clusters, and the Ag-CdO film has almost no change, which shows that the Ag-CdO film has better thermal stability.

c. Stability to moist Heat

In order to research the moist heat stability of the Ag-CdO film, the Ag-CdO film is subjected to a high accelerated aging test under the test conditions of 121 ℃ and 97% RH. The transmittance and sheet resistance change curves measured after the Ag-CdO film is placed in a high accelerated aging experimental box for 12, 24 and 36 hours are shown in FIG. 6, wherein FIG. 6(a) is the transmittance change curve of the Ag-CdO film in a high accelerated aging test; FIG. 6(b) is a square resistance change curve of the Ag-CdO film in a high accelerated aging test. The Ag-CdO film has the advantages that the permeation is increased and the sheet resistance is reduced after a high accelerated aging test, and the Ag-CdO film tends to be stable after 24-36 hours, so that the Ag-CdO film has good damp-heat stability.

Claims

1. A method for preparing a transparent conductive film with a single-layer structure is characterized by comprising the following steps: loading the cleaned substrate into a vacuum chamber of a vacuum magnetron sputtering device, wherein the vacuum degree of the chamber is 1 × 10^-4~7×10^-4When Pa is needed, argon is filled, the total air pressure is controlled to be 0.16Pa, the sputtering power of the target is adjusted to be 10-60W, then a sample baffle is opened, and the surface of the substrate is deposited by adopting a magnetron sputtering method to obtain a transparent conductive film with the thickness of 3-12 nm;

the transparent conductive film is composed of silver and metal oxide; the metal oxide is selected from CdO, ZnO and In₂O₃、SnO₂、MoO₃、ZrO₂、PdO、TiO₂And HfO₂At least one of;

the atomic percentage of the metal oxide in the transparent conductive film is 1-20%.

2. The method for preparing a transparent conductive film having a single-layer structure according to claim 1, wherein the transparent conductive film is composed of Ag and CdO.

3. The method of preparing a transparent conductive film having a single-layer structure as claimed in claim 1, wherein the substrate is glass, PET, PEF or PC.

4. The method according to claim 1, wherein the magnetron sputtering method is a direct sputtering alloy target or a co-sputtering silver and metal oxide target.

5. The method according to claim 1, wherein the sputtering time of the target is 10 to 90 seconds.

6. A transparent conductive film having a single-layer structure, which is produced by the method according to any one of claims 1 to 5.

7. Use of the transparent conductive film having a single-layer structure according to claim 6 in an optoelectronic device.