Device and method for preparing TCO film through magnetron sputtering coating

Abstract

The invention provides a device for preparing a TCO film through magnetron sputtering coating. A vacuum coating chamber of the device internally comprises a target material and a sample holder, and the planes where the target material and the sample holder are located are parallel to each other; the target material is a circular target material; the target material is higher than the sample rack; the sample rack is used for placing a coating substrate; a sample rack baffle plate is arranged above the sample rack, is arranged corresponding to the coating substrate and is used for shielding and exposing the coating substrate on the sample rack when the sample rack baffle plate is closed and opened; and the sample rack is arranged in the edge sputtering range of the target material. The invention further provides a method for preparing the TCO film through magnetron sputtering coating by means of the device. According to the device and the method, the TCO thin film can be prepared through edge sputter coating at the normal temperature, front bombardment of charged particles in plasma on the surface of the substrate and the surface of the film layer is avoided, and therefore sputtering damage to the surface of the film layer and temperature rise of the substrate are avoided.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of vacuum coating, and particularly relates to a device and method for preparing TCO film by magnetron sputtering coating. BACKGROUND

[0002] At present, when using sputtering method for coating, the coating substrate is directly opposite to the target material, which results in that the charged particles in the plasma bombard the surface of the substrate and the film layer. The bombardment of the charged particles easily causes sputtering damage of the film surface and the temperature rise of the substrate, which causes two problems. One is that the coating substrate will be obviously heated under the bombardment of high-energy particles. The other is that after the thin film material is deposited on the substrate to form a film, the film will be bombarded by high-energy oxygen negative ions and electrons, which causes the film structure to be destroyed, the surface roughness to be increased, and the photoelectric performance to be seriously lost. Especially when the solar cell is used as the substrate, the temperature rise of the substrate and the damage of the film caused by the ion bombardment can cause the photoelectric conversion efficiency of the cell to be greatly reduced. On the other hand, the transparent conductive film (TCO) such as AZO (aluminum-doped zinc oxide) and ITO (Sn-doped indium oxide) is often used as a transparent electrode of a solar cell. In the process of preparing the TCO film by using the magnetron sputtering method, the coating substrate is often heated to ensure excellent photoelectric performance. The process heating and the bombardment of the high-energy charged particles on the substrate will finally cause the temperature of the solar cell substrate to be greatly increased. The temperature resistance of the solar cell is generally not more than 150 DEG C, so there is an urgent need for a low-temperature preparation process of the TCO film to ensure that the cell is not damaged by high temperature when the TCO is deposited.

[0003] CN101595241A discloses a sputtering method and sputtering apparatus. It designs a low-temperature, low-damage coating apparatus, the main structure of which consists of a pair of targets with parallel sputtering surfaces or arranged in a V-shape at a small angle. Because charged particles such as plasma and secondary electrons are confined between the two targets, bombardment damage to the film surface by charged particles can be effectively avoided. CN103074586A discloses a low-temperature, low-damage multifunctional composite coating apparatus and method. It provides a low-temperature, low-damage multifunctional composite coating apparatus, which is a vacuum device consisting of a vacuum cavity including two sets of four rectangular non-equilibrium magnetron targets, an ion source, and a workpiece rotating frame. The two sets of non-equilibrium targets are placed side-by-side, with two targets in each set facing each other, allowing for independent or simultaneous operation; the distance between targets and the angle between targets are adjustable. This invention places two identical targets with parallel mirror surfaces, the magnetic poles on the back of the targets being opposite, with the targets and the sputtering cover serving as the cathode and anode, respectively. Plasma is generated between the targets. Sputtered atoms, through collisions with other charged particles in the plasma, move to the workpiece holder on the side of the target and deposit as a thin film. All targets are negatively charged. Under the influence of the electric field, secondary electrons and oxygen anions move back and forth between the targets in a spiral Larmor motion. CN101595241A and CN103074586A share similar device structures; both use a set of targets placed face-to-face to confine charged particles in the plasma between the two targets, thus preventing the thin film from being bombarded by charged particles. Secondly, the two patents differ in the movement of the substrates used for coating. In CN101595241A, the substrate moves linearly along a direction perpendicular to the sputtering surface of the target material, making it suitable for large-area industrial coating. In CN103074586A, the substrate is fixed on a workpiece rotating frame, and a negative bias is applied to the frame. However, the negative bias attracts positively charged particles in the plasma to bombard the film surface. Furthermore, the workpiece rotating frame cannot rotate during coating, leading to uneven film thickness. Neither patent solves the problems of sputtering damage caused by high-energy particle bombardment during the coating process and the degradation of battery performance caused by substrate heating.

[0004] How to provide a low-temperature preparation process for TCO thin films to ensure that solar cells are not damaged by high temperatures during TCO deposition is a problem that the photovoltaic industry urgently needs to solve. Summary of the Invention

[0005] The first objective of this invention is to provide an apparatus for preparing TCO thin films by magnetron sputtering, which can avoid direct bombardment of the substrate and film surface by charged particles in the plasma.

[0006] The second objective of this invention is to provide a method for preparing TCO thin films by magnetron sputtering, using the aforementioned apparatus.

[0007] To achieve the first objective of this invention, the following technical solution is adopted:

[0008] An apparatus for preparing TCO thin films by magnetron sputtering, wherein the vacuum deposition chamber of the apparatus includes a target and a sample holder, the planes of which are parallel to each other;

[0009] The target material is a circular target material;

[0010] The target material is positioned higher than the sample holder;

[0011] The sample holder is used to hold the coated substrate;

[0012] A sample holder baffle is provided above the sample holder and is provided corresponding to the coating substrate, which is used to shield and expose the coating substrate on the sample holder when it is closed and open, respectively.

[0013] The sample holder is positioned within the edge sputtering range of the target material.

[0014] Preferably, in the device of the present invention, the sample holder is a circular sample holder that can rotate around its central axis for placing one of the coated substrates;

[0015] There are multiple sample holders, and they are arranged tangentially around the projection of the target material onto the plane where the sample holder is located.

[0016] In the preferred embodiment of the device of the present invention, the distance between the target material and the sample holder in the vertical direction is 8-20 cm.

[0017] Preferably, in the device of the present invention, the distance between the sample holder and the sample holder baffle in the vertical direction is 0.5-3 cm.

[0018] Preferably, when the sample holder baffle is closed, the device of the present invention can completely block the sample holder and the coated substrate thereon; preferably, when the sample holder baffle is closed, the distance between any edge of the sample holder and the edge of the sample holder baffle is ≥2cm.

[0019] Preferably, in the apparatus of the present invention, the sample holder is an annular sample holder that is rotatable around its central axis, for placing multiple coated substrates in annular arrangement.

[0020] The inner ring edge of the sample holder is tangent to the central axis of the target material.

[0021] In the preferred embodiment of the device of the present invention, the distance between the target material and the sample holder in the vertical direction is 15-30 cm.

[0022] In the preferred embodiment of the device of the present invention, if the outer ring radius of the sample holder is R1 and the radius of the target material is R2, then R1 / R2≥2.

[0023] Preferably, in the device of the present invention, the distance between the sample holder and the sample holder baffle in the vertical direction is 0.5-3 cm.

[0024] Preferably, when the sample holder baffle is closed, the device of the present invention can completely block the corresponding coated substrate on the sample holder; preferably, when the sample holder baffle is closed, the distance between any edge of the corresponding coated substrate on the sample holder and the edge of the sample holder baffle is ≥2cm.

[0025] In the preferred embodiment of the device of the present invention, a target baffle is provided directly below the target material, wherein the radius R3 of the baffle is greater than or equal to the radius R2 of the target material.

[0026] Preferably, R3 / R2 ≤ 1.1.

[0027] Preferably, the distance between the target baffle and the target in the vertical direction is 8-15cm.

[0028] Preferably, the apparatus of the present invention further includes a pumping unit and an Ar flow meter respectively connected to the vacuum coating chamber; the pumping unit includes a mechanical pump, a molecular pump and a pneumatic valve in sequence, and is connected to the vacuum coating chamber through the pneumatic valve.

[0029] To achieve the second objective of the present invention, a method for preparing TCO thin films by magnetron sputtering is also provided, wherein the method is performed using the aforementioned apparatus.

[0030] The method of the present invention, preferably, includes:

[0031] (1) Place the coated substrate on the sample holder with the coated surface facing upwards;

[0032] (2) Vacuum the vacuum coating chamber using the vacuum pumping unit;

[0033] (3) Then Ar gas is introduced into the vacuum coating chamber, the radio frequency power supply is turned on, and the target material is subjected to three-stage pre-sputtering with successively reduced gas pressure.

[0034] (4) Then open the sample holder baffle and start the sample holder rotation to begin depositing a thin film on the coating substrate;

[0035] (5) Stop sputtering and rotating after the predetermined thickness is reached to obtain a thin film.

[0036] In the method of the present invention, preferably, in step (1), the vacuum is evacuated to ≤1×10⁻⁶.-6 Torr.

[0037] In the method of the present invention, preferably, in step (2), the purity of Ar gas is ≥99.999%.

[0038] In the method of the present invention, preferably, in step (3), the gas pressure of a pre-sputtering stage is (1-5)×10⁻⁶. -2 Torr, time 1-3 min; and / or,

[0039] The gas pressure for the second-stage pre-sputtering is (3-6)×10. -3 Torr, time 1-3 min; and / or,

[0040] The gas pressure for the three-stage pre-sputtering is (5-9)×10 -4 Torr, time is 1-3 minutes.

[0041] The beneficial effects of this invention are as follows:

[0042] (1) The apparatus and method of the present invention for preparing TCO thin films by magnetron sputtering use a circular target as a sputtering source. Compared with a square target, the circular target does not have the problem of uneven magnetic field distribution in the length and width directions.

[0043] (2) The apparatus and method of the present invention for preparing TCO thin films by magnetron sputtering coating utilize particles emitted from the edge of the target material for coating, thereby avoiding direct forward bombardment of the substrate by charged particles in the direction perpendicular to the target surface, and protecting the film structure of the prepared TCO thin film as a transparent electrode of the battery cell from damage; at the same time, since the coating substrate is not directly below the target material, it avoids suspended particles in the plasma from falling onto the film layer.

[0044] (3) The apparatus and method of the present invention for preparing TCO thin films by magnetron sputtering utilize edge sputtering to control the sputtering gas pressure at (5-9)×10⁻⁶. -4 Between Torr, TCO thin films with excellent photoelectric properties can be prepared at room temperature, avoiding the adverse effects of substrate heating on battery performance. Attached Figure Description

[0045] Figure 1 This is a three-dimensional perspective view of the vacuum coating chamber of the apparatus for preparing TCO thin films by magnetron sputtering in the first embodiment of the present invention.

[0046] Figure 2 This is a top view of the vacuum coating chamber in the first embodiment of the apparatus for preparing TCO thin films by magnetron sputtering of the present invention.

[0047] Figure 3This is a three-dimensional perspective view of the vacuum coating chamber of the apparatus for preparing TCO thin films by magnetron sputtering in the second embodiment of the present invention.

[0048] Figure 4 This is a top view of the vacuum coating chamber in the second embodiment of the apparatus for preparing TCO thin films by magnetron sputtering of the present invention.

[0049] Figure 5 This is a schematic diagram of the overall structure of the apparatus for preparing TCO thin films by magnetron sputtering according to the present invention. Detailed Implementation

[0050] The technical solution and its effects of the present invention will be further described below with reference to specific embodiments / examples and accompanying drawings. The following embodiments / examples are only for illustrating the content of the present invention, and the invention is not limited to the following embodiments or examples. Simple modifications made to the present invention based on the concept of the present invention are all within the scope of protection claimed by the present invention.

[0051] This invention provides an apparatus for preparing TCO thin films by magnetron sputtering, such as... Figures 1-5 As shown,

[0052] The vacuum coating chamber 1 of the device includes a target 101 and a sample holder 102, and the planes on which the two are located are parallel to each other.

[0053] The target material 101 is a circular target material;

[0054] The target 101 is positioned higher than the sample holder 102;

[0055] The sample holder 102 is used to place the coated substrate 103;

[0056] A sample holder baffle 104 is provided above the sample holder 102 and is provided corresponding to the coating substrate 103, which is used to shield and expose the coating substrate 103 on the sample holder 102 when it is closed and open, respectively.

[0057] The sample holder 102 is located within the edge sputtering range of the target 101.

[0058] This invention relates to an apparatus and method for preparing TCO thin films by magnetron sputtering. A circular target is used as the sputtering source. Compared to a square target, a circular target eliminates the problem of uneven magnetic field distribution along its length and width. The film is deposited using particles emitted from the target edge, avoiding direct bombardment of the substrate by charged particles perpendicular to the target surface, thus protecting the structure of the prepared TCO thin film used as a solar cell from damage. Simultaneously, since the substrate is not directly below the target, suspended particles in the plasma are prevented from falling onto the film. Edge sputtering is used to control the sputtering pressure at (5-9)×10⁻⁶. - 4 Between Torr, TCO thin films with excellent photoelectric properties can be prepared at room temperature, avoiding the adverse effects of substrate heating on battery performance.

[0059] Based on experiments, the inventors speculate that without heating, the energy during edge scattering is low, the bombardment effect is small, the damage to the previously deposited film is small, and the edge sputtering generates more charged ions, which is beneficial for film crystallization and improves conductivity. This allows them to prepare TCO films with excellent photoelectric properties at room temperature.

[0060] In one embodiment, the target material 101 is arranged along the same central axis as the vacuum coating chamber 1.

[0061] In one implementation, such as Figures 1-2 As shown, the sample holder 102 is a circular sample holder and can rotate around its central axis, used to place one of the coated substrates 103.

[0062] There are multiple sample holders 102, and they are arranged tangentially around the projection of the target 101 onto the plane where the sample holder 102 is located.

[0063] In one implementation, such as Figures 1-2 As shown, the vertical distance between the target material 101 and the sample holder 102 is 8-20cm, such as 8cm, 10cm, 12cm, 14cm, 16cm, 18cm and 20cm, and any value and range within this range.

[0064] In one embodiment, the vertical distance between the sample holder 102 and the sample holder baffle 104 is 0.5-3cm, such as 0.5cm, 0.7cm, 0.9cm, 1.2cm, 1.5cm, 2cm and 3cm, and any value and range within this range.

[0065] In one implementation, such as Figures 1-2As shown, when the sample holder baffle 104 is closed, it can completely cover the sample holder 102 and the coated substrate 103 on it; preferably, when the sample holder baffle 104 is closed, the distance between any edge of the sample holder 102 and the edge of the sample holder baffle 104 is ≥2cm, preferably 2-4cm, such as 2cm, 3cm and 4cm and any value and range within this range.

[0066] This arrangement of the present invention ensures that when the sample holder baffle 104 is closed, the surface of the coating substrate is not deposited with thin film material; while when the sample holder baffle 104 is open, the coating substrate is exposed by removing the shield, ensuring that edge sputtering particles are deposited on the coating substrate.

[0067] In one implementation, such as Figures 3-4 As shown, the sample holder 102 is a ring-shaped sample holder and can rotate around its central axis, used to place multiple coating substrates 103 along its ring.

[0068] The inner ring edge of the sample holder 102 is tangent to the central axis of the target material 101.

[0069] In one implementation, such as Figures 3-4 As shown, the vertical distance between the target material 101 and the sample holder 102 is 15-30cm, such as 15cm, 20cm, 25cm and 30cm, and any value and range within this range.

[0070] In one implementation, such as Figures 3-4 As shown, let the outer ring radius of the sample holder 102 be R1 and the radius of the target material 101 be R2, then R1 / R2≥2; preferably R1 / R2=2-4, such as 2, 3, and 4 and any value and range within this range.

[0071] In one implementation, such as Figures 3-4 As shown, the vertical distance between the sample holder 102 and the sample holder baffle 104 is 0.5-1.5cm, such as 0.5cm, 0.7cm, 0.9cm, 1.2cm, 1.5cm, 2cm and 3cm, and any value and range within this range.

[0072] In one implementation, such as Figures 3-4As shown, when the sample holder baffle 104 is closed, it can completely block the corresponding coated substrate 103 on the sample holder 102; preferably, when the sample holder baffle 104 is closed, the distance between any edge of the corresponding coated substrate 103 on the sample holder 102 and the edge of the sample holder baffle 104 is ≥2cm, preferably 2-4cm, such as 2cm, 3cm and 4cm and any value and range within this range.

[0073] This arrangement of the present invention ensures that when the sample holder baffle 104 is closed, the surface of the coating substrate is not deposited with thin film material; while when the sample holder baffle 104 is open, the coating substrate is exposed by removing the shield, ensuring that edge sputtering particles are deposited on the coating substrate.

[0074] In one implementation, such as Figures 3-4 As shown, a target baffle 105 is provided directly below the target 101, and its radius R3 is greater than or equal to the radius R2 of the target 101, that is, R3 / R2 ≥ 1.

[0075] In this invention, the target baffle is used to block sputtered particles emitted from the front of the target, preventing them from depositing on the coating substrate and ensuring that the coating substrate only receives particles sputtered from the edge of the target.

[0076] In one implementation, such as Figures 3-4 As shown, the target material 101 and the target material baffle 105 are arranged on the same central axis.

[0077] In one implementation, such as Figures 3-4 As shown, R3 / R2 is 1-1.1, such as 1, 1.05 and 1.1, and any value and range within this range.

[0078] In one implementation, such as Figures 3-4 As shown, the vertical distance between the target baffle 105 and the target 101 is 8-15cm, such as 8cm, 10cm, 12cm and 15cm and any value within this range.

[0079] In one implementation, such as Figure 5 As shown, the device also includes a pumping unit and an Ar flow meter 2, which are respectively connected to the vacuum coating chamber 1; the pumping unit includes a mechanical pump 301, a molecular pump 302 and a pneumatic valve 303, and is connected to the vacuum coating chamber 1 through the pneumatic valve 303.

[0080] The present invention also provides a method for preparing TCO thin films by magnetron sputtering deposition, wherein the method is performed using the aforementioned apparatus.

[0081] In one implementation, such asFigures 1-5 As shown, the method includes:

[0082] (1) Place the coated substrate 103 on the sample holder 102 with the coated surface facing upward;

[0083] (2) Vacuum the vacuum coating chamber 1 using the vacuum pumping unit;

[0084] (3) Then Ar gas is introduced into the vacuum coating chamber 1, the radio frequency power supply is turned on, and the target material 101 is subjected to three-stage pre-sputtering with successively decreasing gas pressure; specifically: after introducing Ar gas until the gas pressure reaches the first stage pre-sputtering gas pressure, the radio frequency power supply is turned on to perform the first stage pre-sputtering; then the gas pressure is adjusted to the second stage pre-sputtering gas pressure to perform the second stage pre-sputtering; then the gas pressure is adjusted to the third stage pre-sputtering gas pressure to perform the third stage pre-sputtering.

[0085] (4) Then open the sample holder baffle 104 and start the sample holder 2 to rotate, and begin depositing a thin film on the coating substrate 103;

[0086] (5) Stop sputtering and rotating after the predetermined thickness is reached to obtain a thin film.

[0087] In this invention, during steps (1)-(3), the sample holder baffle 104 is always in a closed state, i.e., a blocking state; during steps (1)-(4), the target baffle 105 is always in a closed state, i.e., a blocking state.

[0088] After obtaining the thin film in step (5) of the present invention, it is taken out by filling the vacuum coating chamber 1 with nitrogen gas to break the air.

[0089] In one implementation, in step (1), the vacuum is evacuated to ≤1×10 -6 Torr.

[0090] In one implementation, in step (2), the purity of Ar gas is ≥99.999%.

[0091] In one implementation, in step (2), the flow rate of Ar gas is 10-30 sccm, such as 10 sccm, 20 sccm, 30 sccm and any value and range within that range.

[0092] In one embodiment, in step (3), the gas pressure of a pre-sputtering section is (1-5)×10⁻⁶. -2 Torr, for example, 1×10 -2 Torr, 2×10 -2 Torr, 3×10 -2 Torr, 4×10 -2 Torr, 5×10 -2Torr and any value and range within that range; the time is 1-3 minutes, such as 1 minute, 2 minutes, 3 minutes and any value and range within that range.

[0093] In one embodiment, in step (3), the gas pressure of the second-stage pre-sputtering is (3-6)×10⁻⁶. -3 Torr, for example, 3×10 -3 Torr, 4×10 -3 Torr, 5×10 -3 Torr, 6×10 -3 Torr and any value and range within that range; the time is 1-3 minutes, such as 1 minute, 2 minutes, 3 minutes and any value and range within that range.

[0094] In one embodiment, in step (3), the gas pressure of the three pre-sputtering stages is (5-9)×10. -4 Torr, for example, 5×10 -4 Torr, 6×10 -4 Torr, 7×10 -4 Torr, 8×10 -4 Torr, 9×10 -4 Torr and any value and range within that range; the time is 1-3 minutes, such as 1 minute, 2 minutes, 3 minutes and any value and range within that range.

[0095] In one embodiment, in step (3), the sputtering power is set according to the target area, preferably with a target sputtering power density of 1.5-2.5 W / cm². 2 For example, 1.5W / cm 2 2W / cm 2 2.5W / cm 2 and any value within that range and the range of values.

[0096] In this invention, the TCO thin film includes AZO thin film (aluminum-doped zinc oxide thin film) and ITO (sn-doped indium oxide thin film). When preparing the corresponding TCO thin film, the coating substrate used is the corresponding substrate, such as glass sheet, polymer material, solar cell device, etc.

[0097] In one embodiment, in step (4), the rotational speed of the sample holder 2 is 5-20 r / min, such as 5 r / min, 10 r / min, 15 r / min, 20 r / min and any value and range within that range.

[0098] This invention provides a method for preparing TCO thin films by magnetron sputtering, using the aforementioned apparatus. A circular target is used as the sputtering source, which, compared to a square target, eliminates the problem of uneven magnetic field distribution along its length and width. Deposition is performed using particles emitted from the target edge, avoiding direct bombardment of the substrate by charged particles perpendicular to the target surface, thus protecting the TCO thin film structure as a solar cell from damage. Simultaneously, since the substrate is not directly below the target, suspended particles in the plasma are prevented from falling onto the film. Edge sputtering is used to control the sputtering pressure at (5-9) × 10⁻⁶. -4 Between Torr, TCO thin films with excellent photoelectric properties can be prepared at room temperature, avoiding the adverse effects of substrate heating on battery performance.

[0099] Raw materials used in the following examples / comparative examples:

[0100] Unless otherwise specified, all raw materials and reagents used in this invention are commercially available and used directly without processing.

[0101] Example 1 (S1)

[0102] Utilize Figure 1 The apparatus shown deposits AZO thin films, and the method includes:

[0103] (1) Clean the coated substrate 103 (glass slide) with deionized water and dry it with nitrogen gas, then place it on the sample holder 102 with the coated surface facing up.

[0104] (2) The vacuum coating chamber 1 is evacuated to 8×10 using the vacuum pumping unit. -7 Torr;

[0105] (3) Then, Ar gas (purity ≥ 99.999%) is introduced into the vacuum coating chamber 1 at a flow rate of 20 sccm until the gas pressure reaches a pre-sputtering pressure of 2 × 10⁻⁶. -2 After torsion, turn on the RF power and perform a 3-minute pre-sputtering stage; then adjust the gas pressure to the second-stage pre-sputtering pressure of 3×10⁻⁶. -3 After Torr, perform a second-stage pre-sputtering for 1 minute; then adjust the gas pressure to the third-stage pre-sputtering pressure of 7 × 10⁻⁶. -4 After Torr, perform three-stage pre-sputtering for 1 minute;

[0106] (4) Then open the sample holder baffle 104 and start the sample holder 102 to rotate at a speed of 10 r / min to begin depositing a thin film on the coating substrate 103.

[0107] (5) After deposition for 30 minutes, stop sputtering and rotation, turn off the Ar gas, fill the vacuum coating chamber 1 with nitrogen gas to break the air, and take out the obtained AZO film, which is recorded as film sample 1.

[0108] Example 2 (S2)

[0109] Utilize Figure 2 The apparatus shown was used to deposit an AZO thin film. The method and experimental parameters were the same as in Example 1. An AZO thin film was obtained and denoted as film sample 2.

[0110] Example 3 (S3)

[0111] Utilize Figure 1 The apparatus shown was used to deposit an ITO thin film. The method and experimental parameters were the same as in Example 1. An ITO thin film was obtained and denoted as film sample 3.

[0112] Comparative Example 1 (D1)

[0113] Using the same experimental parameters, AZO thin films were prepared in a conventional coating equipment (target facing the coating substrate), denoted as film sample 1'.

[0114] result

[0115] The electrical properties of membranes 1-3 obtained in Examples 1-3 and membrane 1' obtained in Comparative Example 1 were tested using a four-probe tester. The test results are shown in Table 1.

[0116] Table 1 Test Results

[0117]

[0118] A comparison of the embodiments and comparative examples shows that:

[0119] Without heating the substrate, the resistivity of AZO and ITO films prepared by conventional sputtering using conventional coating equipment is more than 300 times greater than the conductivity of AZO films obtained by edge sputtering using the coating equipment of the present invention. This indicates that edge sputtering using the coating equipment of the present invention can effectively improve the conductivity of TCO films.

Claims

1. An apparatus for preparing TCO thin films by magnetron sputtering, characterized in that, The vacuum coating chamber (1) of the device includes a target (101) and a sample holder (102), and the planes on which the two are located are parallel to each other; The target material (101) is a circular target material; The target material (101) is positioned higher than the sample holder (102); The sample holder (102) is used to place the coated substrate (103); A sample holder baffle (104) is provided above the sample holder (102) and is provided corresponding to the coating substrate (103) to shield and expose the coating substrate (103) on the sample holder (102) when closed and open, respectively. The sample holder (102) is located within the edge sputtering range of the target material (101).

2. The apparatus according to claim 1, characterized in that, The sample holder (102) is a circular sample holder and can rotate around its central axis to hold one of the coated substrates (103). There are multiple sample holders (102), and they are arranged tangentially around the projection of the target material (101) onto the plane where the sample holder (102) is located.

3. The apparatus according to claim 2, characterized in that, The vertical distance between the target material (101) and the sample holder (102) is 8-20 cm; and / or, The vertical distance between the sample holder (102) and the sample holder baffle (104) is 0.5-3 cm; and / or, When the sample holder baffle (104) is closed, it can completely cover the sample holder (102) and the coated substrate (103) on it; preferably, when the sample holder baffle (104) is closed, the distance between any edge of the sample holder (102) and the edge of the sample holder baffle (104) is ≥2cm, preferably 2-4cm.

4. The apparatus according to claim 1, characterized in that, The sample holder (102) is a ring-shaped sample holder and can rotate around its central axis, for placing multiple coating substrates (103) along its ring. The inner ring edge of the sample holder (102) is tangent to the central axis of the target material (101).

5. The apparatus according to claim 4, characterized in that, The vertical distance between the target material (101) and the sample holder (102) is 15-30 cm; and / or, Let the outer radius of the sample holder (102) be R1 and the radius of the target material (101) be R2, then R1 / R2 ≥ 2; and / or, The vertical distance between the sample holder (102) and the sample holder baffle (104) is 0.5-3 cm; and / or, When the sample holder baffle (104) is closed, it can completely cover the corresponding coated substrate (103) on the sample holder (102); preferably, when the sample holder baffle (104) is closed, the distance between any edge of the corresponding coated substrate (103) on the sample holder (102) and the edge of the sample holder baffle (104) is ≥2cm, preferably 2-4cm.

6. The apparatus according to claim 4 or 5, characterized in that, If a target baffle (105) is provided directly below the target (101), then its radius R3 is greater than or equal to the radius R2 of the target (101). Preferably, R3 / R2 ≤ 1.1; and / or, The distance between the target baffle (105) and the target (101) in the vertical direction is 8-15 cm; and / or.

7. The apparatus according to any one of claims 1-6, characterized in that, The device also includes a pumping unit and an Ar flow meter (2) respectively connected to the vacuum coating chamber (1); the pumping unit includes a mechanical pump (301), a molecular pump (302) and a pneumatic valve (303) in sequence, and is connected to the vacuum coating chamber (1) through the pneumatic valve (303).

8. A method for preparing TCO thin films by magnetron sputtering deposition, characterized in that, The method is performed using the apparatus described in any one of claims 1-7.

9. The method according to claim 8, characterized in that, The method includes: (1) Place the coated substrate (103) on the sample holder (102) with the coated surface facing upwards; (2) Vacuum the vacuum coating chamber (1) using the vacuum pumping unit; (3) Then Ar gas is introduced into the vacuum coating chamber (1), the radio frequency power supply is turned on, and the target material (101) is subjected to three-stage pre-sputtering with successively reduced gas pressure. (4) Then open the sample holder baffle (104) and start the sample holder (102) to rotate, and begin depositing a thin film on the coating substrate (103); (5) Stop sputtering and rotating after the predetermined thickness is reached to obtain a thin film.

10. The method according to claim 9, characterized in that, In step (1), the vacuum is evacuated to ≤1×10 -6 Torr; and / or, In step (2), the purity of Ar gas is ≥99.999%; and / or, In step (3), the gas pressure of a pre-sputtering section is (1-5)×10 -2 Torr, time 1-3 min; and / or, The gas pressure for the second-stage pre-sputtering is (3-6)×10. -3 Torr, time 1-3 min; and / or, The gas pressure for the three-stage pre-sputtering is (5-9)×10 -4 Torr, time is 1-3 minutes.

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