Method for depositing thin film on substrate, application of method, semiconductor device and application of semiconductor device

Abstract

The invention relates to the technical field of semiconductors, in particular to a method for depositing a thin film on a substrate, application of the method, a semiconductor device and application of the semiconductor device. The method is carried out in an evaporation chamber containing a crystal oscillator and comprises the following steps that S1, the doping proportion of doping materials in a thin film is determined, and the doping materials comprise at least one organic compound and / or polymer and at least one transition metal oxide; s2, determining the evaporation conditions of the doping materials, so that the ratio of the stable evaporation rates of the doping materials is the doping ratio of the doping materials in the thin film; and S3, each doping material is evaporated on the substrate at the respective stable evaporation rate. The doping material is evaporated in the evaporation cavity containing the crystal oscillator, the prepared semiconductor device doped film is accurate in doping proportion and excellent in conductivity, and devices prepared by applying the semiconductor device doped film to organic electroluminescent devices and solar cells are excellent in performance.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a method for depositing a thin film on a substrate and an application thereof, and a semiconductor device and an application thereof. Background Art

[0002] After nearly half a century of development and improvement, the research on inorganic semiconductor materials and their materials has become a leader in the electronics industry. With the advancement of science and technology, organic functional materials with semiconductor properties are gradually entering the field of semiconductor materials. In the 1980s, Dr. Qingyun Deng of Eastman Kodak proposed organic photovoltaic cells (Ref. Applied Physics Letters 1986, 48(2): 183-185) and organic light-emitting diode devices (Ref. Applied Physics Letters 1986, 51(12): 913-915), which respectively achieved photoelectric conversion and electroluminescence in organic devices, laying a solid foundation for the practical application of organic semiconductor materials.

[0003] The rapid development of organic semiconductor materials and devices is due to their unique advantages, such as simple film-forming technology and preparation process, low cost, light weight and good flexibility. Compared with inorganic semiconductors, organic semiconductors have very low intrinsic carrier concentration. For example, the carriers in organic electroluminescent devices need to be injected from the anode or cathode, and then migrate to the designated functional layer by "jumping". Their carrier mobility and concentration are significantly lower than those of inorganic semiconductors. Achieving energy level matching at the electrode / organic interface and improving the carrier density of the organic layer are of great significance for high-efficiency organic semiconductor devices. Studies have shown that the use of buffer materials between the electrode and the transport layer (Ref. Journal of Applied Physics 2013, 114: 244505) can effectively reduce the carrier injection barrier of the device. In addition, the addition of other materials to organic materials can also significantly increase the carrier density (Ref. Physics Status Solidi A 2012, 209 (8): 1399-1413).

[0004] As the performance of organic semiconductor devices can be improved by doping functional layers of two or more materials, the determination of the doping ratio is crucial. CN110596027A discloses a device and a method for measuring the doping ratio of a thin film. The three indicators of light responsiveness, light-to-dark current ratio, and I / V curve are tested on a specific sensor device to improve the measurement accuracy of the doping ratio. At present, when doping materials are deposited on a glass substrate in proportion to form a film, there are mainly two ways: First, the doping ratio process of the two materials is monitored in real time by two or more crystal oscillators. Second, the two materials are dissolved in a solvent such as alcohol in a specified mass ratio. After the alcohol evaporates, the fused two materials are placed in the same evaporating dish, and then deposited into a film by thermal evaporation. The evaporation rate is monitored in real time by a crystal oscillator. Summary of the Invention

[0005] Existing doping methods have certain shortcomings. They are either separated from the device preparation process, affecting the subsequent device performance optimization; or the randomness of the molecular path after the material evaporation reduces the accuracy of the ratio of the two materials deposited into the doped film; or due to the differences in the melting point, density, atomic binding energy and other properties of the two materials, the evaporation temperature is also very different. When a certain current value is used for evaporation, it is impossible to ensure that the two materials are deposited into films in the same proportion during the entire evaporation process, resulting in inaccurate doping ratios.

[0006] The purpose of the present invention is to overcome the problems in the prior art that the doping ratio of doped films in semiconductor devices is difficult to determine and the doping accuracy is low, and to provide a method for depositing a thin film on a substrate and its application, as well as a semiconductor device and its application. The method has the characteristics of simple operation process, wide application range, and the ability to determine the doping ratio during the material preparation process and ensure the subsequent performance optimization of the material.

[0007] In order to achieve the above-mentioned objectives, the first aspect of the present invention provides a method for depositing a thin film on a substrate, which is carried out in an evaporation chamber containing a crystal oscillator, and includes the following steps: S1, determining the doping ratio between each doping material in the thin film, the doping material comprising at least one organic compound and / or polymer and at least one transition metal oxide; S2, determining the evaporation conditions of each doping material so that the ratio of the stable evaporation rates of each doping material is the doping ratio between each doping material in the thin film; S3, evaporating each doping material on the substrate at its own stable evaporation rate.

[0008] A second aspect of the present invention provides an application of the method described in the first aspect in preparing a semiconductor device.

[0009] A third aspect of the present invention provides a semiconductor device prepared by the application described in the second aspect.

[0010] A fourth aspect of the present invention provides an application of the semiconductor device described in the third aspect in an organic electroluminescent device and a solar cell.

[0011] Through the above technical solution, the present invention has the following advantages:

[0012] The present invention simultaneously evaporates doping materials in an evaporation chamber containing a crystal oscillator to prepare a semiconductor device doped film with precise doping ratio and excellent conductive performance. The devices prepared in organic electroluminescent devices and solar cells have excellent performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a flow chart of the present invention for depositing a thin film using a glass substrate as a base;

[0014] Figure 2 is a schematic structural diagram of the semiconductor device prepared in Example 1;

[0015] Figure 3 1 is a normalized absorption spectrum diagram of the doped film and the undoped film in Example 1;

[0016] Figure 4 is a schematic diagram of electron transfer between MoO3 and NPB in Example 1;

[0017] Figure 5 1 is a current density-voltage curve diagram of the devices to be tested prepared in Examples 1-6 and Comparative Example 1;

[0018] Figure 6 It is a schematic diagram of the components inside the evaporation chamber;

[0019] Figure 7 It is the evaporation rate-time diagram of the doping material during the evaporation process. DETAILED DESCRIPTION

[0020] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0021] The present invention provides a method for depositing a thin film on a substrate, which is performed in an evaporation chamber containing a crystal oscillator and includes the following steps: S1, determining the doping ratio between each doping material in the thin film, where the doping material includes at least one organic compound and / or polymer and at least one transition metal oxide; S2, determining the evaporation conditions of each doping material so that the ratio of the stable evaporation rates of each doping material is the doping ratio between the each doping material in the thin film; S3, evaporating each doping material on the substrate at its own stable evaporation rate.

[0022] The present invention simultaneously evaporates doping materials in an evaporation chamber containing a crystal oscillator to prepare a semiconductor device doped film with precise doping ratio and excellent conductive performance. The devices prepared in organic electroluminescent devices and solar cells have excellent performance.

[0023] According to a preferred embodiment of the present invention, the volume ratio of the organic compound and / or polymer to the transition metal oxide in the doping material is 0.01-10, for example, 0.01, 0.05, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10, preferably 0.1-10, and more preferably 1-2. By adopting the above preferred embodiment, the doping ratio of the two materials can be precisely controlled, thereby further improving the conductive properties of the prepared semiconductor device.

[0024] According to a preferred embodiment of the present invention, the transition metal is selected from at least one of Group VB metals, Group VIB metals, and Group VIII metals, preferably a Group VIB metal, and more preferably Mo and / or W. By adopting the aforementioned preferred embodiment, the doping ratio of the two materials can be precisely controlled, thereby further improving the conductive properties of the prepared semiconductor device.

[0025] In order to further accurately control the doping ratio of the two materials, thereby further improving the conductivity of the prepared semiconductor device, according to a preferred embodiment of the present invention, the organic compound is a P-type conductive organic compound, preferably at least one of NPB, CuPc and CBP.

[0026] In order to further precisely control the doping ratio of the two materials, thereby further improving the conductive properties of the prepared semiconductor device, according to a preferred embodiment of the present invention, the polymer is a P-type semiconductor polymer, preferably PTAA and / or PEDOT:PSS.

[0027] According to a preferred embodiment of the present invention, the film comprises NPB and molybdenum oxide. Preferably, the volume ratio of NPB to molybdenum oxide is 0.01-10, for example, 0.01, 0.05, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, preferably 0.1-10, more preferably 1-2. By adopting the above preferred embodiment, the doping ratio of the two materials can be precisely controlled, thereby further improving the conductive properties of the prepared semiconductor device.

[0028] According to a preferred embodiment of the present invention, the film thickness is 20-80 nm, for example, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, and 80 nm. By adopting the above preferred embodiment, the doping ratio of the two materials can be precisely controlled, thereby further improving the conductive properties of the prepared semiconductor device.

[0029] According to a preferred embodiment of the present invention, the substrate contains a semiconductor material, preferably a glass substrate coated with a semiconductor material, that is, a glass sheet coated with a semiconductor material.

[0030] In order to further improve the conductive performance of the film, according to a preferred embodiment of the present invention, the thickness of the glass substrate is 0.5-2 mm, for example, 0.5 mm, 1 mm, 1.5 mm and 2 mm.

[0031] In order to further improve the conductive performance of the film, according to a preferred embodiment of the present invention, the sheet resistance of the glass substrate is 10-50Ω, for example, 10Ω, 20Ω, 30Ω, 40Ω and 50Ω.

[0032] In order to further improve the conductive performance of the film, according to a preferred embodiment of the present invention, the light transmittance of the glass substrate is not less than 85%, for example, 85%, 88%, 90%, 92% and 95%, preferably 88-90%.

[0033] According to a preferred embodiment of the present invention, the thickness of the semiconductor material coating on the glass substrate is 50-150 nm, for example, 50 nm, 70 nm, 80 nm, 100 nm, 120 nm, 130 nm, and 150 nm. By adopting the above preferred solution, the conductive properties of the film can be further improved.

[0034] According to a preferred embodiment of the present invention, the semiconductor material is an organic semiconductor material and / or an inorganic semiconductor material, preferably an inorganic semiconductor material, more preferably indium tin oxide (ITO) and / or fluorine-doped tin oxide (FTO).

[0035] According to a preferred embodiment of the present invention, step S2 includes: evaporating any doping material on the substrate, and measuring the evaporation rate of the doping material using a crystal oscillator. The evaporation rate is calculated as follows:

[0036] V=-(Hz n -Hz n-1 ) / △T

[0037] Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 5-20s, for example, △T = 5s, △T = 10s, △T = 15s, △T = 20s, and the "-" is because the displayed value of the crystal oscillator decreases as the material is deposited. At the same time, the duration of stable evaporation is recorded; and based on the stable evaporation rate of the doping material, the evaporation conditions of the remaining doping materials are adjusted so that the ratio of the stable evaporation rates of the doping materials becomes the doping ratio between the doping materials in the film.

[0038] According to a preferred embodiment of the present invention, the evaporation conditions include: the absolute vacuum degree in the evaporation chamber is 0-10 -3 Pa, for example, 10 -3 Pa, 10 -4 Pa, 10 -5 Pa, 10 -6 Pa and 10 -7 Pa, preferably 10 -4 -10 -3 Pa.

[0039] In the present invention, the evaporation time is determined based on the shortest duration of the stable evaporation rate among the durations of the stable evaporation rates of the doping materials and the evaporation thickness.

[0040] In the present invention, the duration of stable evaporation of the doping material is determined by the evaporation rate.

[0041] According to a preferred embodiment of the present invention, the evaporation conditions include: the stable evaporation rate of the organic compound and / or polymer is For example it could be and Preferably The stable evaporation rate of the transition metal oxide is For example it could be and Preferably By adopting the aforementioned preferred solution, the doping ratio of the two materials can be accurately controlled, thereby further improving the conductive properties of the prepared semiconductor device.

[0042] In order to further accurately control the doping ratio of the two materials, thereby further improving the conductive properties of the prepared semiconductor device, according to a preferred embodiment of the present invention, the evaporation conditions include: the ratio of the stable evaporation rate of the organic compound and / or polymer to the transition metal oxide is 0.01-10:1, for example, it can be 0.01:1, 0.05:1, 0.1:1, 0.5:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 and 10:1, preferably 0.1-10:1, and more preferably 1-2:1.

[0043] According to a preferred embodiment of the present invention, the substrate is pretreated before evaporation.

[0044] According to a preferred embodiment of the present invention, the pretreatment step includes: ultrasonically cleaning the substrate with a cleaning agent, drying the substrate, and then performing ozone treatment.

[0045] In the present invention, there is no special requirement for the conditions of the ultrasonic cleaning. It is illustrated for illustrative purposes only and does not limit the scope of the present invention. For example, the conditions of the ultrasonic cleaning include: an ultrasonic frequency of 40-90 KHz, for example, 40 KHz, 50 KHz, 60 KHz, 70 KHz, 80 KHz and 90 KHz.

[0046] In the present invention, there is no particular requirement for the ultrasonic cleaning time, as long as it can be cleaned. According to a preferred embodiment of the present invention, the ultrasonic cleaning time is 10-30 minutes, for example, 10 minutes, 14 minutes, 18 minutes, 20 minutes, 23 minutes, 27 minutes and 30 minutes.

[0047] In the present invention, as long as the purpose of the present invention can be achieved, there is no special requirement for the type of the cleaning agent. This is an exemplary description, but it does not limit the scope of the present invention. According to a preferred embodiment of the present invention, the cleaning agent is selected from at least one of water, ethanol and isopropanol.

[0048] In this application, as long as the purpose of the present invention can be achieved, there is no special requirement for the amount of the cleaning agent. According to a preferred embodiment of the present invention, the amount of the cleaning agent is 100-400 mL, for example, 100 mL, 200 mL, 300 mL and 400 mL.

[0049] In the present invention, the purpose of the present invention can be achieved as long as ozone treatment is carried out. The optional range of ozone treatment conditions is relatively wide. The following exemplary description does not limit the scope of the present invention. According to a preferred embodiment of the present invention, the ozone treatment conditions include: the ozone treatment time is 10-20 minutes, for example, 10 minutes, 12 minutes, 15 minutes, 18 minutes and 20 minutes.

[0050] In the present invention, the following exemplary description is given for step S2: a first current value is applied to a first container containing a first doping material placed in a heating source area, the substrate baffle is opened, the initial frequency value of the crystal oscillator is recorded, and the display value of the crystal oscillator is recorded every 10 seconds until the first doping material in the first container is completely evaporated. After the first doping material is evaporated, the current value drops to 0, and the substrate baffle is closed to its original position; a second current value is applied to a second container containing a second doping material placed in a heating source area, the substrate baffle is opened, the initial frequency value of the crystal oscillator is recorded, and the display value of the crystal oscillator is recorded every 10 seconds until the second doping material in the second container is completely evaporated. After the second doping material is evaporated, the current value drops to 0, and the substrate baffle is closed to its original position; wherein, the first current value and the second current value are controlled through different current channels.

[0051] According to a preferred embodiment of the present invention, the current is determined according to the melting point of the doping material to be evaporated.

[0052] According to a preferred embodiment of the present invention, the method comprises the following steps:

[0053] 1) Substrate pretreatment: ultrasonically clean and dry the substrate using a cleaning agent, and then perform ozone treatment;

[0054] 2) Evaporation preparation: Take the pretreated substrate as the sample substrate, place the sample substrate at the corresponding position of the mask plate in the vacuum evaporation chamber, and place the containers containing different doping materials in different heating source areas;

[0055] 3) Determine the evaporation conditions of each doping material:

[0056] First, determine the stable evaporation rate and duration of stable evaporation of any dopant material. The method includes: applying current to a container containing the dopant material, recording the initial frequency value of a crystal oscillator, and recording the display value of the crystal oscillator every ΔT until the dopant material in the container is completely evaporated. After the dopant material evaporates, the current value drops to 0. The evaporation rate is calculated as follows:

[0057] V=-(Hz n -Hz n-1 ) / △T

[0058] Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 5-20s, for example, △T = 5s, △T = 10s, △T = 15s, △T = 20s; "-" is because the displayed value of the crystal oscillator decreases as the material is deposited.

[0059] Then, based on the stable evaporation rate of the doping material, the evaporation conditions of the remaining doping materials are adjusted so that the ratio of the stable evaporation rates of the doping materials is the doping ratio between the doping materials in the film;

[0060] 4) In an evaporation chamber containing a crystal oscillator, each doping material is evaporated on the substrate at its own stable evaporation rate under the evaporation conditions determined in step 3).

[0061] According to a preferred embodiment of the present invention, the method further includes: verifying the evaporation results, retaining the evaporation process of any dopant material, and confirming whether the frequency change value of the crystal oscillator is the stable evaporation rate of the dopant material.

[0062] The invention provides an application of the method in preparing a semiconductor device.

[0063] The present invention provides a semiconductor device prepared by the application.

[0064] The present invention provides an application of the semiconductor device in an organic electroluminescent device and a solar cell.

[0065] According to a preferred embodiment of the present invention, Figure 1 The flowchart shown is used to prepare semiconductor devices. The specific steps are as follows: first, the substrate is pretreated, then the evaporation preparation is performed, and then the evaporation conditions of each doping material are determined, and finally a thin film with a specific thickness and doping ratio is evaporated.

[0066] The present invention will be described in detail below through examples. In the following examples, all the processes are carried out in the evaporation chamber. The schematic diagram of the interior of the evaporation chamber is shown in FIG. Figure 6 As shown, there is only one crystal oscillator; the square resistance of the glass substrate is measured by a four-probe method; the transmittance of the glass substrate is measured on a transmittance tester; the absorption spectrum is measured on an ultraviolet-visible light spectrometer; unless otherwise specified, the raw materials are all commercially available.

[0067] Example 1

[0068] according to Figure 2 A doping layer consisting of MoO3 and NPB is deposited on an ITO-coated alkaline earth boroaluminosilicate glass sheet, wherein the doping layer has a thickness of 50 nm and the volume ratio of MoO3 to NPB is 1:1. The preparation steps are as follows:

[0069] Determine the evaporation conditions of each doping material:

[0070] (1) A glass substrate containing ITO was cleaned with 200 mL of water, 200 mL of ethanol, and 200 mL of isopropanol at an ultrasonic frequency of 40 kHz for 30 minutes, dried, and then subjected to ozone treatment for 12 minutes. The glass substrate had a thickness of 1 mm, a square resistance of 50 Ω, and a transmittance of 88%, and the ITO thickness was 100 nm.

[0071] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with MoO3 and the quartz crucible filled with NPB in the designated heating source area, close the chamber and start vacuuming;

[0072] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -4 At Pa, evaporation begins;

[0073] (4) Apply a current of 50 A to the tungsten boat containing MoO3, open the substrate shutter, record the initial frequency value of the crystal oscillator, and then record it every 10 seconds until the material in the tungsten boat is completely evaporated; after the material evaporation is completed, the current value drops to 0, and the substrate shutter is closed to its original position;

[0074] The evaporation rate of the material in each interval is:

[0075] V=-(Hz n -Hz n-1 ) / △T

[0076] Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 10s; "-" is because the displayed value of the crystal oscillator decreases as the material is deposited

[0077]

[0078] (5) The changes in the MoO3 evaporation rate values ​​obtained by observation and calculation are as follows Figure 7 As shown, the stable evaporation rate of MoO3 is The duration is 12 minutes;

[0079] (6) Similarly, the same operation was performed on the quartz crucible containing NPB to determine the stable evaporation rate of NPB. The evaporation conditions at this time were tested. When the applied current was 41A, the stable evaporation rate of NPB was The duration is 5 minutes;

[0080] Evaporation: In an evaporation chamber containing a crystal oscillator, each dopant material is evaporated onto the substrate at its own stable evaporation rate under certain evaporation conditions:

[0081] (1) A glass substrate containing ITO was cleaned with 200 mL of water, 200 mL of ethanol, and 200 mL of isopropanol at an ultrasonic frequency of 40 kHz for 30 minutes, dried, and then subjected to ozone treatment for 12 minutes. The glass substrate had a thickness of 1 mm, a square resistance of 50 Ω, and a transmittance of 88%, and the ITO thickness was 100 nm.

[0082] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with MoO3 and the quartz crucible filled with NPB in the designated heating source area, close the chamber and start vacuuming;

[0083] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -4 At Pa, evaporation begins;

[0084] (4) Apply the same current value of 50A to the tungsten boat filled with MoO3 and heat it to the time when the material has a stable evaporation rate. Then apply the corresponding current value of 41A to the quartz crucible filled with NPB to make the two materials evaporate at the same time. When the evaporation rate of the two materials reaches When the substrate baffle is opened, during this period, the frequency change value of the crystal oscillator is guaranteed to be stable within When the actual change in the frequency of the crystal oscillator (the change in the frequency of the crystal oscillator between opening and closing the substrate) reaches 500 Hz (i.e., 50 nm), the substrate baffle is closed and the evaporation is completed;

[0085] Verify the evaporation results, retain the evaporation process of any dopant material, and confirm whether the frequency change value of the crystal oscillator is the stable evaporation rate of the dopant material:

[0086] (1) First, reduce the current value of NPB to 0 and continue to observe the frequency change of the crystal oscillator. After a period of time, confirm that the organic material NPB stops evaporating and observe the frequency change of the crystal oscillator. The corresponding rate at this time is the evaporation rate of MoO3, which should be consistent with the stable evaporation rate.

[0087] (2) The proportion of the stable evaporation rate of MoO3 in the stable rate controlled when the two materials evaporate simultaneously is the doping ratio of MoO3 in the doped film NPB:MoO3.

[0088] Normalized absorption spectra of doped film NPB:MoO3 and undoped film are shown in Figure 2. Figure 3 As shown in the figure, the absorption peak of NPB film at 350nm wavelength and the absorption peak at 500nm wavelength are derived from the charge transfer complex generated by the molecular transfer between MoO3 and NPB (NPB + -MoO3 - ) absorption peak; Among them, the charge transfer complex dissociates under the applied voltage, and the electrons are captured by MoO3 with a deep energy level electronic structure, leaving mobile holes in NPB, thereby increasing the carrier concentration in the device and greatly improving the device conductivity; the energy level structure and charge transfer path of NPB and MoO3 are as follows Figure 4 shown.

[0089] Under the same vacuum environment (10 -4 Pa), Al was deposited on the prepared device to obtain the device under test, the structure of which was: glass sheet (1mm) / ITO (100nm) / NPB:MoO3 (50nm) / Al (100nm). After the device under test was prepared in a vacuum environment, it was taken out and tested at room temperature in an unpackaged state. The test equipment was a digital source meter (Keithley2400). The ITO of the device under test was connected to the positive electrode of the test equipment, and the Al was connected to the negative electrode of the test equipment. The current density value of the device under test was observed under a given driving voltage. Figure 5 As shown in the figure, at a driving voltage of 2V, the current density values ​​of the device under test are 2529.59mA / cm 2 .

[0090] Example 2

[0091] and Figure 2 The structure is similar. A doping layer composed of MoO3 and CBP is deposited on an alkaline earth boroaluminosilicate glass sheet coated with FTO. The doping layer thickness is 30nm and the volume ratio of CBP to MoO3 is 3:1. The preparation steps are as follows:

[0092] Determine the evaporation conditions of each doping material:

[0093] (1) A glass substrate containing FTO was cleaned with 100 mL of water, 100 mL of ethanol, and 100 mL of isopropanol at an ultrasonic frequency of 60 kHz for 20 minutes, dried, and then subjected to ozone treatment for 12 minutes. The thickness of the glass substrate was 0.5 mm, the square resistance was 20 Ω, the transmittance was 89%, and the thickness of the ITO was 70 nm.

[0094] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with MoO3 and the quartz crucible filled with CBP in the designated heating source area, close the chamber and start vacuuming;

[0095] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -3 At Pa, evaporation begins;

[0096] (4) Apply a current of 50 A to the tungsten boat containing MoO3, open the substrate shutter, record the initial frequency value of the crystal oscillator, and then record it every 5 seconds until the material in the tungsten boat is completely evaporated; after the material evaporation is completed, the current value drops to 0, and the substrate shutter is closed to its original position;

[0097] The evaporation rate of the material in each interval is:

[0098] V=-(Hz n -Hz n-1 ) / △T

[0099] Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 5s; "-" is because the displayed value of the crystal oscillator decreases as the material is deposited

[0100]

[0101] (5) The changes in the MoO3 evaporation rate values ​​obtained by observation and calculation are as follows Figure 7 As shown, the stable evaporation rate of MoO3 is The duration is 12 minutes;

[0102] (6) Similarly, the same operation was performed on the quartz crucible containing CBP to determine the stable evaporation rate of CBP. The evaporation conditions at this time were tested. When the applied current was 60A, the stable evaporation rate of CBP was The duration is 3 minutes;

[0103] Evaporation: In an evaporation chamber containing a crystal oscillator, each dopant material is evaporated onto the substrate at its own stable evaporation rate under certain evaporation conditions:

[0104] (1) A glass substrate containing ITO was cleaned with 100 mL of water, 100 mL of ethanol, and 100 mL of isopropanol at an ultrasonic frequency of 60 kHz for 20 minutes, dried, and then subjected to ozone treatment for 12 minutes. The thickness of the glass substrate was 0.5 mm, the square resistance was 20 Ω, the transmittance was 89%, and the FTO thickness was 70 nm.

[0105] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with MoO3 and the quartz crucible filled with CBP in the designated heating source area, close the chamber and start vacuuming;

[0106] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -4 At Pa, evaporation begins;

[0107] (4) Apply the same current value of 50A to the tungsten boat filled with MoO3 and heat it to the time when the material has a stable evaporation rate. Then apply the corresponding current value of 60A to the quartz crucible filled with CBP to make the two materials evaporate simultaneously. When the substrate baffle is opened, during this period, ensure that the frequency change value of the crystal oscillator is stable at this value. When the actual change in the frequency of the crystal oscillator (the change in the frequency of the crystal oscillator between opening and closing the substrate) reaches 300 Hz (i.e., 30 nm), the substrate baffle is closed and the evaporation is completed;

[0108] Verify the evaporation results, retain the evaporation process of any dopant material, and confirm whether the frequency change value of the crystal oscillator is the stable evaporation rate of the dopant material:

[0109] (1) First, reduce the current value of CBP to 0 and continue to observe the frequency change of the crystal oscillator. After a period of time, confirm that the organic material CBP stops evaporating and observe the frequency change of the crystal oscillator. The corresponding rate at this time is the evaporation rate of MoO3, which should be consistent with the stable evaporation rate;

[0110] (2) The proportion of the stable evaporation rate of MoO3 in the controlled stable rate when the two materials evaporate simultaneously is the doping ratio of MoO3 in the doped film CBP:MoO3.

[0111] Normalized absorption spectrum of doped thin film and Figure 3 similar.

[0112] Under the same vacuum environment (10 -3Pa), Al was deposited on the prepared device to obtain the device to be tested, the structure of which was: glass sheet (0.5mm) / FTO (70nm) / CBP:MoO3 (30nm) / Al (100nm). After the device to be tested was prepared in a vacuum environment, it was taken out and tested in a room temperature environment in an unpackaged state. The test equipment was a digital source meter (Keithley2400). The FTO of the device to be tested was connected to the positive electrode of the test equipment, and Al was connected to the negative electrode of the test equipment. The current density value of the device to be tested was observed under a given driving voltage. Figure 5 As shown in the figure, at a driving voltage of 2V, the current density values ​​of the device under test are 561.83mA / cm 2 .

[0113] Example 3

[0114] and Figure 2 The structure is similar. A doping layer consisting of WO3 and CuPc is deposited on an ITO-coated alkaline earth boron aluminosilicate glass wafer. The doping layer thickness is 80nm and the volume ratio of WO3 to CuPc is 1:1. The preparation steps are as follows:

[0115] Determine the evaporation conditions of each doping material:

[0116] (1) A glass substrate containing ITO was cleaned with 300 mL of water, 300 mL of ethanol, and 300 mL of isopropanol at an ultrasonic frequency of 80 kHz for 23 minutes, dried, and then subjected to ozone treatment for 18 minutes. The glass substrate had a thickness of 1.5 mm, a square resistance of 45 Ω, and a transmittance of 90%, and the ITO thickness was 150 nm.

[0117] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with WO3 and the quartz crucible filled with CuPc in the designated heating source area, close the chamber and start vacuuming;

[0118] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -4 At Pa, evaporation begins;

[0119] (4) Apply a current of 63A to the tungsten boat containing WO3, open the substrate shutter, record the initial frequency value of the crystal oscillator, and then record it every 15 seconds until the material in the tungsten boat is completely evaporated; after the material evaporation is completed, the current value drops to 0, and the substrate shutter is closed to its original position;

[0120] The evaporation rate of the material in each interval is:

[0121] V=-(Hz n -Hz n-1 ) / △T

[0122] Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 15s; "-" is because the displayed value of the crystal oscillator decreases as the material is deposited

[0123]

[0124] (5) The changes in the WO3 evaporation rate values ​​obtained by observation and calculation are as follows Figure 7 As shown, the stable evaporation rate of WO3 is The duration is 15 minutes;

[0125] (6) Similarly, the same operation was performed on the quartz crucible containing CuPc to determine the stable evaporation rate of CuPc. The evaporation conditions at this time were tested. When the applied current was 45A, the stable evaporation rate of CuPc was The duration is 5.5 minutes;

[0126] Evaporation: In an evaporation chamber containing a crystal oscillator, each dopant material is evaporated onto the substrate at its own stable evaporation rate under certain evaporation conditions:

[0127] (1) A glass substrate containing ITO was cleaned with 300 mL of water, 300 mL of ethanol, and 300 mL of isopropanol at an ultrasonic frequency of 80 kHz for 23 minutes, dried, and then subjected to ozone treatment for 18 minutes. The glass substrate had a thickness of 1.5 mm, a square resistance of 45 Ω, and a transmittance of 90%, and the ITO thickness was 150 nm.

[0128] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with WO3 and the quartz crucible filled with CuPc in the designated heating source area, close the chamber and start vacuuming;

[0129] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -4 At Pa, evaporation begins;

[0130] (4) Apply the same current value of 63A to the tungsten boat filled with WO3 and heat it to the time when the material has a stable evaporation rate. Then apply the corresponding current value of 45A to the quartz crucible filled with CuPc to make the two materials evaporate at the same time. When the evaporation rate of the two materials reaches During this period, ensure that the frequency change value of the crystal oscillator is stable at this value. When the actual frequency change of the crystal oscillator (the change of the crystal oscillator between opening and closing the substrate) reaches 800 Hz (ie 80 nm), the substrate baffle is closed and the evaporation is completed.

[0131] Verify the evaporation results, retain the evaporation process of any dopant material, and confirm whether the frequency change value of the crystal oscillator is the stable evaporation rate of the dopant material:

[0132] (1) First, reduce the current value of CuPc to 0 and continue to observe the frequency change of the crystal oscillator. After a period of time, confirm that the organic material CuPc stops evaporating and observe the frequency change of the crystal oscillator. The corresponding rate at this time is the evaporation rate of WO3, which should be consistent with the stable evaporation rate;

[0133] (2) The proportion of the stable evaporation rate of WO3 in the controlled stable rate when the two materials evaporate simultaneously is the doping ratio of WO3 in the doped film CuPc:WO3.

[0134] Normalized absorption spectrum of doped thin film and Figure 3 similar.

[0135] Under the same vacuum environment (10 -4 Pa), Al was deposited on the prepared device to obtain the device under test, the structure of which was: glass sheet (1.5mm) / ITO (150nm) / CuPc:WO3 (80nm) / Al (100nm). After the device under test was prepared in a vacuum environment, it was taken out and tested in an unpackaged state at room temperature. The test equipment was a digital source meter (Keithley2400). The ITO of the device under test was connected to the positive electrode of the test equipment, and the Al was connected to the negative electrode of the test equipment. The current density value of the device under test was observed under a given driving voltage. Figure 5 As shown in Figure 2, at a driving voltage of 2V, the current density values ​​of the device under test are 1566.70mA / cm 2 .

[0136] Example 4

[0137] and Figure 2 The structure is similar. A doping layer composed of MoO3 and PTAA is deposited on an ITO-coated alkaline earth boron aluminosilicate glass sheet. The doping layer thickness is 50nm and the volume ratio of MoO3 to PTAA is 1:1. The preparation steps are as follows:

[0138] Determine the evaporation conditions of each doping material:

[0139] (1) A glass substrate containing ITO was cleaned with 200 mL of water, 200 mL of ethanol, and 200 mL of isopropanol at an ultrasonic frequency of 40 kHz for 30 minutes, dried, and then subjected to ozone treatment for 12 minutes. The glass substrate had a thickness of 1 mm, a square resistance of 50 Ω, and a transmittance of 88%, and the ITO thickness was 100 nm.

[0140] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with MoO3 and the quartz crucible filled with PTAA in the designated heating source area, close the chamber and start vacuuming;

[0141] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -4 At Pa, evaporation begins;

[0142] (4) Apply a current of 50 A to the tungsten boat containing MoO3, open the substrate shutter, record the initial frequency value of the crystal oscillator, and then record it every 10 seconds until the material in the tungsten boat is completely evaporated; after the material evaporation is completed, the current value drops to 0, and the substrate shutter is closed to its original position;

[0143] The evaporation rate of the material in each interval is:

[0144] V=-(Hz n -Hz n-1 ) / △T

[0145] Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 10s; "-" is because the displayed value of the crystal oscillator decreases as the material is deposited

[0146]

[0147] (5): The changes in the MoO3 evaporation rate values ​​obtained by observation and calculation are as follows Figure 7 As shown, the stable evaporation rate of MoO3 is The duration is 12 minutes;

[0148] (6) Similarly, the same operation was performed on the quartz crucible containing PTAA to determine the stable evaporation rate of PTAA. The evaporation conditions at this time were tested. When the applied current was 44A, the stable evaporation rate of PTAA was The duration is 6 minutes;

[0149] Evaporation: In an evaporation chamber containing a crystal oscillator, each dopant material is evaporated onto the substrate at its own stable evaporation rate under certain evaporation conditions:

[0150] (1) A glass substrate containing ITO was cleaned with 200 mL of water, 200 mL of ethanol, and 200 mL of isopropanol at an ultrasonic frequency of 40 kHz for 30 minutes, dried, and then subjected to ozone treatment for 12 minutes. The glass substrate had a thickness of 1 mm, a square resistance of 50 Ω, and a transmittance of 88%, and the ITO thickness was 100 nm.

[0151] (2) Place the treated glass substrate at the corresponding position of the mask plate in the evaporation chamber, place the tungsten boat filled with MoO3 and the quartz crucible filled with PTAA in the designated heating source area, close the chamber and start vacuuming;

[0152] (3) The absolute vacuum degree in the evaporation chamber reaches 10 -4 At Pa, evaporation begins;

[0153] (4) Apply the same current value of 50A to the tungsten boat filled with MoO3 and heat it to the time when the material has a stable evaporation rate. Then apply the corresponding current value of 44A to the quartz crucible filled with PTAA to make the two materials evaporate at the same time. When the evaporation rate of the two materials reaches When the substrate baffle is opened, during this period, ensure that the frequency change value of the crystal oscillator is stable at this value. When the actual change in the frequency of the crystal oscillator (the change in the frequency of the crystal oscillator between opening and closing the substrate) reaches 500 Hz (i.e., 50 nm), the substrate baffle is closed and the evaporation is completed;

[0154] Verify the evaporation results, retain the evaporation process of any dopant material, and confirm whether the frequency change value of the crystal oscillator is the stable evaporation rate of the dopant material:

[0155] (1) First, reduce the current value of PTAA to 0 and continue to observe the frequency change of the crystal oscillator. After a period of time, confirm that the organic material PTAA stops evaporating and observe the frequency change of the crystal oscillator. The corresponding rate at this time is the evaporation rate of MoO3, which should be consistent with the stable evaporation rate;

[0156] (2) The proportion of the stable evaporation rate of MoO3 in the stable rate controlled when the two materials evaporate simultaneously is the doping ratio of MoO3 in the doped film PTAA:MoO3.

[0157] Normalized absorption spectrum of doped thin film and Figure 3 similar.

[0158] Under the same vacuum environment (10 -4Pa), Al was deposited on the prepared device to obtain the device under test, the structure of which was: glass sheet (1mm) / ITO (100nm) / PTAA:MoO3 (50nm) / Al (100nm). After the device under test was prepared in a vacuum environment, it was taken out and tested at room temperature in an unpackaged state. The test equipment was a digital source meter (Keithley2400). The ITO of the device under test was connected to the positive electrode of the test equipment, and the Al was connected to the negative electrode of the test equipment. The current density value of the device under test was observed under a given driving voltage. Figure 5 As shown in the figure, at a driving voltage of 2V, the current density values ​​of the device under test are 1487.90mA / cm 2 .

[0159] Example 5

[0160] According to Example 1, the difference is that MoO3 is replaced by WO3, and the current applied to the tungsten boat containing WO3 is 63A. Through observation and calculation, it is found that the stable evaporation rate of WO3 is The duration is 15 minutes.

[0161] Normalized absorption spectrum of doped thin film and Figure 3 similar.

[0162] Under the same vacuum environment (10 -4 Pa), Al was deposited on the prepared device to obtain the device under test, the structure of which was: glass sheet (1mm) / ITO (100nm) / NPB:WO3 (50nm) / Al (100nm). After the device under test was prepared in a vacuum environment, it was taken out and tested at room temperature in an unpackaged state. The test equipment was a digital source meter (Keithley2400). The ITO of the device under test was connected to the positive electrode of the test equipment, and the Al was connected to the negative electrode of the test equipment. The current density value of the device under test was observed under a given driving voltage. Figure 5 As shown in the figure, at a driving voltage of 2V, the current density values ​​of the device under test are 1689.59mA / cm 2 .

[0163] Example 6

[0164] The method is as in Example 1, except that the volume ratio of NPB to MoO3 is 10:1, and the current applied to the quartz crucible containing NPB is 57A, so that the stable evaporation rate of NPB is The current applied to the quartz crucible containing MoO3 is 41A, which makes the stable evaporation rate of MoO3 The duration of stable evaporation of NPB is 1.5 min, and the duration of stable evaporation of MoO3 is 20 min.

[0165] Normalized absorption spectrum of doped thin film and Figure 3 Similar; the energy level structure and charge transfer path of NPB and MoO3 are as follows Figure 4 shown.

[0166] Under the same vacuum environment (10 -4 Pa), Al was deposited on the prepared device to obtain the device under test, the structure of which was: glass sheet (1mm) / ITO (100nm) / NPB:MoO3 (50nm) / Al (100nm). After the device under test was prepared in a vacuum environment, it was taken out and tested at room temperature in an unpackaged state. The test equipment was a digital source meter (Keithley2400). The ITO of the device under test was connected to the positive electrode of the test equipment, and the Al was connected to the negative electrode of the test equipment. The current density value of the device under test was observed under a given driving voltage. Figure 5 As shown in the figure, at a driving voltage of 2V, the current density values ​​of the device under test are 112.47mA / cm 2 .

[0167] Comparative Example 1

[0168] The same method as in Example 1 is used except that the current applied to the tungsten boat containing MoO3 is 0A when preparing the doped thin film of the device. At this time, the evaporation rate of MoO3 is

[0169] The normalized absorption spectrum of the undoped film is shown in Figure 2. Figure 3 shown.

[0170] Under the same vacuum environment (10 -4 Pa), Al was deposited on the prepared device to obtain the device under test, the structure of which was: glass sheet (1mm) / ITO (100nm) / NPB (50nm) / Al (100nm). After the device under test was prepared in a vacuum environment, it was taken out and tested at room temperature in an unpackaged state. The test equipment was a digital source meter (Keithley2400). The ITO of the device under test was connected to the positive electrode of the test equipment, and the Al was connected to the negative electrode of the test equipment. The current density value of the device under test was observed under a given driving voltage. Figure 5 As shown in the figure, at a driving voltage of 2V, the current density values ​​of the device under test are 6.80mA / cm 2 .

[0171] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for depositing a thin film on a substrate, characterized in that: The method is carried out in an evaporation chamber containing a crystal oscillator and includes the following steps: S1. determining a doping ratio between various doping materials in the thin film, where the doping materials comprise at least one organic compound and / or polymer and at least one transition metal oxide; S2. Determine the evaporation conditions of each dopant material so that the ratio of the stable evaporation rates of each dopant material is the doping ratio between the doping materials in the thin film; S3. Each doping material is evaporated onto the substrate at its own stable evaporation rate.

2. The method according to claim 1, characterized in that The volume ratio of the organic compound and / or polymer to the transition metal oxide in the doping material is 0.01-10, preferably 0.1-10, more preferably 1-2.

3. The method according to claim 1 or 2, characterized in that The transition metal is selected from at least one of Group VB metals, Group VIB metals and Group VIII metals, preferably a Group VIB metal, more preferably Mo and / or W.

4. The method according to any one of claims 1 to 3, characterized in that The organic compound is a P-type conductive organic compound.

5. The method according to any one of claims 1 to 4, characterized in that The organic compound is selected from at least one of NPB, CuPc and CBP.

6. The method according to any one of claims 1 to 5, characterized in that The polymer is a P-type semiconductor polymer.

7. The method according to any one of claims 1 to 6, characterized in that The polymer is PTAA and / or PEDOT:PSS.

8. The method according to any one of claims 1 to 7, characterized in that The film comprises NPB and molybdenum oxide. Preferably, the volume ratio of NPB to molybdenum oxide is 0.01-10, preferably 0.1-10, and more preferably 1-2.

9. The method according to any one of claims 1 to 8, characterized in that The film thickness is 20-80 nm; and / or The substrate contains semiconductor material, preferably a glass substrate coated with semiconductor material, preferably, The thickness of the glass substrate is 0.5-2 mm; and / or the sheet resistance of the glass substrate is 10-50 Ω; and / or the light transmittance of the glass substrate is not less than 85%, preferably 88-90%.

10. The method according to claim 9, characterized in that The coating thickness of the semiconductor material in the glass substrate is 50-150 nm; The semiconductor material is preferably an organic semiconductor material and / or an inorganic semiconductor material, preferably an inorganic semiconductor material, more preferably indium tin oxide and / or fluorine-doped tin oxide.

11. The method according to any one of claims 1 to 10, characterized in that Step S2 includes: Any doping material is evaporated on the substrate, and the evaporation rate of the doping material is tested using a crystal oscillator. The evaporation rate is calculated as follows: V=-(Hz n -Hz n-1 ) / △T Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 5-20s; at the same time, record the duration of stable evaporation; Then, based on the stable evaporation rate of the doping material, the evaporation conditions of the remaining doping materials are adjusted so that the ratio of the stable evaporation rates of the doping materials becomes the doping ratio between the doping materials in the film.

12. The method according to any one of claims 1 to 11, characterized in that The evaporation conditions include: the absolute vacuum degree in the evaporation chamber is 0-10 -3 Pa, preferably 10 -4 -10 -3 Pa.

13. The method according to any one of claims 1 to 12, characterized in that The evaporation conditions include: the stable evaporation rate of the organic compound and / or polymer is The stable evaporation rate of the transition metal oxide is Preferably, the ratio of the stable evaporation rate of the organic compound and / or polymer to the transition metal oxide is 0.01-10:

1.

14. The method according to any one of claims 1 to 13, wherein: The evaporation conditions include: the stable evaporation rate of the organic compound and / or polymer is The stable evaporation rate of the transition metal oxide is Preferably, the ratio of the stable evaporation rate of the organic compound and / or polymer to the transition metal oxide is 0.1-10:1, preferably 1-2:

1.

15. The method according to any one of claims 1 to 14, characterized in that The substrate is pretreated before vapor deposition, and the pretreatment steps include: ultrasonically cleaning the substrate with a cleaning agent, drying the substrate, and then performing ozone treatment.

16. The method according to any one of claims 1 to 15, characterized in that The method comprises the following steps: 1) Substrate pretreatment: ultrasonically clean and dry the substrate using a cleaning agent, and then perform ozone treatment; 2) Evaporation preparation: Take the pretreated substrate as the sample substrate, place the sample substrate at the corresponding position of the mask plate in the vacuum evaporation chamber, and place the containers containing different doping materials in different heating source areas; 3) Determine the evaporation conditions of each doping material: First, determine the stable evaporation rate and duration of stable evaporation of any dopant material. The method includes: applying current to a container containing the dopant material, recording the initial frequency value of a crystal oscillator, and recording the display value of the crystal oscillator every ΔT until the dopant material in the container is completely evaporated. After the dopant material evaporates, the current value drops to 0. The evaporation rate is calculated as follows: V=-(Hz n -Hz n-1 ) / △T Where V is the evaporation rate, unit Hz n The value displayed by the crystal oscillator at time n; Hz n-1 is the value displayed by the crystal oscillator at time n-1; △T is the difference between time n and time (n-1), △T = 5-20s; Then, based on the stable evaporation rate of the doping material, the evaporation conditions of the remaining doping materials are adjusted so that the ratio of the stable evaporation rates of the doping materials is the doping ratio between the doping materials in the film; 4) In an evaporation chamber containing a crystal oscillator, each doping material is evaporated on the substrate at its own stable evaporation rate under the evaporation conditions determined in step 3).

17. The method according to any one of claims 1 to 16, characterized in that The method further includes: verifying the evaporation result, retaining the evaporation process of any doping material, and confirming whether the frequency change value of the crystal oscillator is the stable evaporation rate of the doping material.

18. Use of the method according to any one of claims 1 to 17 in the preparation of semiconductor devices.

19. The semiconductor device obtained by the application of claim 18.

20. Use of the semiconductor device according to claim 19 in organic electroluminescent devices and solar cells.

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