Electrochromic device coating process and method

Abstract

The invention relates to the technical field of electrochromism coating, in particular to an electrochromism device coating process and method, and the electrochromism device coating process comprises the following steps: step 1, substrate pretreatment: cleaning attachments on the surface of a flexible substrate through ultrasonic cleaning and plasma treatment; step 2, conducting layer deposition treatment: depositing an indium tin oxide (ITO) conducting layer on the substrate at the deposition temperature of 100-380 DEG C, the thickness of 200-350 nm and the vacuum degree of less than or equal to 10 <-5 > Pa; step 3, electrochromic layer deposition treatment: sequentially depositing a tungsten oxide (WO3) layer and a nickel oxide (NiO) layer through a magnetron sputtering process, and controlling the film thickness ratio of NiO to WO3 to enable the ratio of NiO / W to be 0.25-0.357; 4, annealing treatment is conducted, specifically, annealing is conducted for the first time at the temperature of 200-500 DEG C, and the annealing time is 200-300 seconds; and secondary annealing is conducted, specifically, annealing is conducted at the temperature of 400 DEG C, and the annealing time ranges from 200 seconds to 800 seconds. The effect of improving the yellow ground color of the electrochromic device is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of electrochromic coating, and in particular to a coating process and method for an electrochromic device. Background Art

[0002] The electrochromic coating process is a technology that regulates the optical properties of materials through electric fields. It is widely used in smart windows, automotive anti-glare rearview mirrors, energy-saving display screens and other fields. Currently, inorganic all-solid-state electrochromic devices based on tungsten oxide (WO3) and nickel oxide (NiO) generally have a yellow background problem, which greatly affects the visual effect of the device.

[0003] In related technologies, when solving the problem of yellow background color in electrochromic devices, the yellow background color is usually improved by reducing the thickness of the ITO layer, but this results in a significant increase in the surface resistance. When the background color is neutralized by doping excessive metal oxides, although the background color can be neutralized, additional target materials and process adjustments are required, which increases production complexity and cost.

[0004] Regarding the above-mentioned related technologies, adjusting the thickness of the ITO layer or neutralizing the background color by doping transition metal oxides both bring different problems, making it difficult to effectively solve the yellow background color problem of the electrochromic device. Summary of the Invention

[0005] In order to improve the yellow background problem of the electrochromic device and reduce the yellow background problem, the present application provides an electrochromic device coating process and method.

[0006] In a first aspect, the present application provides an electrochromic device coating process, which adopts the following technical solution:

[0007] A coating process for an electrochromic device, comprising:

[0008] Step 1: pre-treatment of the substrate, cleaning the surface of the flexible substrate by ultrasonic cleaning and plasma treatment;

[0009] Step 2: Deposition of conductive layer: depositing an indium tin oxide (ITO) conductive layer on the substrate at a deposition temperature of 100 to 380°C, a thickness of 200 to 350 nm, and a vacuum degree of ≤10 -5 Pa;

[0010] Step 3: Electrochromic layer deposition: a tungsten oxide (WO3) layer and a nickel oxide (NiO) layer are sequentially deposited by magnetron sputtering, with the NiO and WO3 film thickness ratio controlled to achieve a NiO / W ratio of 0.25 to 0.357.

[0011] Step 4: annealing treatment. The first annealing treatment is performed at 200-500° C. for 200-300 seconds. The second annealing treatment is performed at 400° C. for 200-800 seconds.

[0012] By adopting the above technical solution, according to the comprehensive process of substrate pretreatment, conductive layer deposition (deposition temperature 100-380℃, thickness 200-350nm), electrochromic layer deposition (NiO / W ratio 0.25-0.357) and staged annealing, the yellow background color of the electrochromic device is significantly reduced. For example, the b value of the EC layer after optimization is reduced from 19 in the traditional process to below 12, while avoiding the increase in square resistance caused by reducing the ITO thickness. The photoelectric performance is maintained by controlling the NiO / W ratio, reducing the problems of "limited effect of a single optimization path" and "complex doping process", and achieving compatibility with industrial mass production.

[0013] Optionally, in step three, the NiO / W ratio is preferably 0.25-0.357, and is achieved by magnetron sputtering a pure metal nickel target and a tungsten target, with a sputtering spacing of 5-15 cm and a substrate temperature of 100-300°C.

[0014] By adopting the above technical solution, the NiO / W ratio is preferably limited to 0.25-0.357, and the film layer ratio is precisely controlled by magnetron sputtering pure metal nickel target and tungsten target (sputtering spacing 5-15 cm, substrate temperature 100-300°C) to avoid prolonged discoloration speed caused by too low a ratio, while ensuring that the initial transmittance is stable at above 87.5%, taking into account both background color improvement and functional integrity.

[0015] Optionally, in step 2, the first annealing temperature is 200° C., and the annealing time is 300 seconds; the second annealing temperature is 400° C., and the annealing time is 500 seconds.

[0016] By adopting the above technical solution, the first annealing is preferably performed at 200°C / 300 seconds and the second annealing is performed at 400°C / 500 seconds. The stress of the film layer is released by low-temperature annealing (such as the original transmittance of 55.8% is increased to 81.7%) and the lattice structure is optimized by high-temperature annealing, so that the background b value is effectively reduced. Compared with the traditional single annealing process, the transmittance is increased by more than 25%, and the total annealing time is controlled within 800 seconds, which effectively improves the efficiency.

[0017] Optionally, in step 4, the total duration of the first annealing and the second annealing is 500 to 1100 seconds, and the temperature gradient is first low and then high.

[0018] By adopting the above technical solution, the film cracking caused by direct high-temperature treatment is avoided through staged annealing (for example, the transmittance fluctuation of the film is less than 1% after annealing at 500°C). At the same time, the low-temperature stage (200°C) is combined with the high-temperature stage (400°C) to reduce defects and improve density, so that the final background color b value is stabilized below 12, and the device reliability is significantly enhanced.

[0019] Optionally, between step 3 and step 4, the following steps may also be included:

[0020] Transition metal oxide doping treatment, co-sputtering zirconium oxide (ZrO) in the nickel oxide layer, the power ratio of the nickel target to the ZrO target is 1:0.5 to 1:1.2, and the transmittance of the film layer after doping is increased to 12.7% to 77.6%.

[0021] By adopting the above technical solution, zirconium oxide (ZrO) is co-sputtered in the nickel oxide layer (the power ratio of nickel target to ZrO target is 1:0.5~1:1.2, and the doping ratio NiO:ZrO=9:1~7:3). The doping uniformity is improved through the interlayer co-sputtering method, and the background color b value approaches neutral (for example, the b value after doping is reduced from 8.6 to 7.1), achieving background color optimization without excessively increasing costs, and the process is flexible and controllable.

[0022] Optionally, the doping adopts a sandwich co-sputtering method, the sputtering power of the nickel target and the ZrO target are independently controlled, and the total doping ratio is NiO:ZrO=9:1~7:3.

[0023] By adopting the above technical solution, the total doping ratio of the nickel target and the ZrO target can be further adjusted and optimized, which helps to improve the transmittance of the film layer.

[0024] Optionally, the thickness of the conductive layer is preferably 250-300 nm, the square resistance is ≤12Ω / sq, and the initial transmittance is ≥72%.

[0025] By adopting the above technical solution, the temperature control is carried out in stages to balance the square resistance and transmittance, solving the contradiction of "reducing thickness and increasing resistance" in traditional processes. At the same time, the background color b value is further reduced to achieve dual optimization of optical and electrical performance.

[0026] In a second aspect, the present application provides a method for coating an electrochromic device, which adopts the following technical solution:

[0027] A method for coating an electrochromic device, comprising:

[0028] include:

[0029] Collecting nickel oxide / tungsten oxide ratio parameters during electrochromic layer deposition, and calculating multiple sets of optimized ratio parameters according to a preset decreasing ratio;

[0030] The target material is subjected to magnetron sputtering treatment based on the optimized ratio parameters to obtain an electrochromic layer, and the color change value of the electrochromic layer is analyzed to see whether it meets the preset base color parameters;

[0031] When the preset background color parameters are not met, the optimized ratio parameters are adjusted downward and optimized ratio feedback parameters are generated.

[0032] By adopting the above technical solution, the NiO / W ratio parameters are dynamically collected and optimized according to a preset decreasing ratio (such as gradually reducing from 0.564 to 0.25), combined with magnetron sputtering (substrate temperature 100°C, sputtering spacing 10 cm), the background color parameters (such as b value ≤ 12, transmittance ≥ 72%) are analyzed in real time, and feedback parameters are quickly generated to adjust the process, shortening the development cycle (such as traditional trial and error requires multiple rounds of experiments, this method reduces the number of debugging times by 50% through algorithm iteration), and limiting the target material purity and ambient temperature (200-300°C) to ensure consistency in mass production and avoid performance fluctuations caused by human errors.

[0033] Optionally, during magnetron sputtering treatment, the target materials are pure metal tungsten and pure metal nickel, and the substrate temperature is adjusted to 100° C., the ambient temperature is within the range of 200-300° C., and the sputtering distance is 10 cm.

[0034] In summary, this application includes at least one of the following beneficial technical effects:

[0035] 1. A comprehensive process of substrate pretreatment, conductive layer deposition, electrochromic layer deposition, and staged annealing significantly reduces the yellow background color of electrochromic devices while avoiding the increase in sheet resistance caused by reducing the ITO thickness. By controlling the NiO / W ratio, the optoelectronic performance is maintained, alleviating the problems of "limited effectiveness of a single optimization path" and "complex doping process."

[0036] 2. The NiO / W ratio is optimized to 0.25-0.357, and the film ratio is precisely controlled by magnetron sputtering pure metal nickel and tungsten targets (sputtering spacing 5-15 cm, substrate temperature 100-300°C) to avoid prolonged discoloration caused by too low a ratio, while balancing base color improvement and functional integrity.

[0037] 3. Zirconia is co-sputtered into the nickel oxide layer, and the doping uniformity is improved through interlayer co-sputtering. The background color b value approaches neutral, and the background color is optimized without excessively increasing the cost. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of this application more clear, the application is further described in detail below. It should be understood that the specific embodiments described here are only used to explain this application and are not used to limit this application.

[0039] The embodiments of the present invention are described in further detail below with reference to the appended tables of the specification.

[0040] The embodiments of the present application disclose a coating process for an electrochromic device. According to a comprehensive process of substrate pretreatment, conductive layer deposition, electrochromic layer deposition and staged annealing, the yellow background color of the electrochromic device is significantly reduced, while avoiding the increase in square resistance caused by reducing the ITO thickness. The photoelectric performance is maintained by controlling the NiO / W ratio, reducing the problems of "limited effect of a single optimization path" and "complex doping process".

[0041] A method for coating an electrochromic device includes the following steps:

[0042] Step 1: Substrate pretreatment. Substrate pretreatment is the initial step of the process. Ultrasonic cleaning and plasma treatment are used to thoroughly clean the surface of the flexible substrate to remove attached contaminants and activate the surface to ensure the uniformity and adhesion of subsequent film deposition.

[0043] Step 2: Deposition of conductive layer: using magnetron sputtering process to deposit indium tin oxide (ITO) conductive layer on the pre-treated substrate. During the deposition process, the temperature is controlled in stages (e.g. 100℃ or 380℃ in the first stage, vacuum degree ≤10 - 5 In the second stage, the ITO layer thickness was optimized to 200-350 nm by adjusting the temperature (room temperature) and target sputtering rate. Experimental data showed that at a thickness of 250 nm, the sheet resistance was 12 Ω / sq, the initial transmittance reached 79%, and the background b-value dropped to 0.7 (Table 1). This effectively balances conductivity and optical performance, avoiding the traditional contradiction of simply reducing the thickness and resulting in an increase in sheet resistance (e.g., 15 Ω / sq at 200 nm).

[0044] Step three, electrochromic layer deposition treatment, sequentially depositing tungsten oxide (WO3) and nickel oxide (NiO) layers. By magnetron sputtering pure metal tungsten target and nickel target, controlling the sputtering distance (5-15cm), substrate temperature (100-300℃) and film thickness ratio, the NiO / W ratio is precisely adjusted to 0.25-0.357. For example, when the ratio is 0.357, the initial transmittance is increased to 87.5%, and the color change speed is shortened to 60 seconds (Table 3), while a ratio that is too low (such as 0.13) will cause the color change time to be extended to 119 seconds.

[0045] To further optimize the background color, zirconium oxide (ZrO) can be co-sputtered into the nickel oxide layer. Using a sandwich co-sputtering method (nickel target to ZrO target power ratio of 1:0.5 to 1:1.2, doping ratio NiO:ZrO = 9:1 to 7:3), the transmittance of the film layer increased from 61% of pure co-sputtering to 77.6%, and the background color b value decreased from 8.6 to 7.1 (Table 3);

[0046] Step 4, annealing, is performed in two stages. The first annealing is performed at 200-500°C for 200-300 seconds to release film stress and reduce defects. A second annealing is then performed at 400°C for 200-800 seconds to optimize the lattice structure. The preferred method is a first annealing at 200°C / 300 seconds and a second annealing at 400°C / 500 seconds. Under these conditions, the original transmittance significantly increased from 55.8% to 81.7%, and the background b-value remained stable below 12 (see Tables 4-1 and 4-2).

[0047] In addition, the total annealing time is controlled within 500 to 1100 seconds and the temperature gradient is low at first and then high, avoiding cracking of the film layer caused by direct high-temperature treatment and ensuring that the transmittance fluctuation is less than 1%.

[0048] Based on the same inventive concept, an embodiment of the present invention provides a method for coating an electrochromic device, comprising:

[0049] Step S100: collecting nickel oxide / tungsten oxide ratio parameters during the electrochromic layer deposition process, and calculating according to a preset decreasing ratio to obtain multiple sets of optimized ratio parameters;

[0050] The ratio parameter refers to the thickness ratio of nickel oxide (NiO) to tungsten oxide (WO3) in the electrochromic layer. For example, NiO / W = 0.357 means the NiO layer is 0.357 times thicker than the WO3 layer. The preset decreasing ratio represents a parameter adjustment gradient set by technicians (e.g., decreasing by 0.1) to gradually narrow the range of NiO / W ratio values.

[0051] Initial parameter collection uses an initial ratio (e.g., NiO / W = 0.564, as shown in Table 3) obtained from existing processes. This ratio yields an initial device transmittance of 80.3%, but the underlying b-value is relatively high (0.78 to 3.13). A descending ratio experiment generates multiple parameter sets along a preset gradient (e.g., 0.564 → 0.464 → 0.364 → 0.264 → 0.25). Sputtering tests are then performed sequentially, and performance data recorded to identify the optimal range (0.25 to 0.357).

[0052] Step S200: performing magnetron sputtering on the target material based on the optimized ratio parameters to obtain an electrochromic layer, and analyzing whether the color change value of the electrochromic layer meets the preset background color parameters;

[0053] The magnetron sputtering parameters include target type, substrate temperature, ambient temperature, and sputtering spacing. The color change value of the electrochromic layer is measured by a colorimeter, with the target b value being ≤ 12 (as shown in the optimized data in Table 1).

[0054] Step S300: When the preset background color parameters are not met, the optimized ratio parameters are adjusted downward, and optimized ratio feedback parameters are generated;

[0055] If the test results do not meet the target (for example, b value > 12 or transmittance < 72%), the system automatically triggers parameter down-regulation, gradually reducing the NiO / W ratio according to a preset decreasing ratio (such as 0.1), re-sputtering and testing, and finally generating the optimal parameters (such as NiO / W = 0.25) and storing them in the process database.

[0056] Among them, during the magnetron sputtering treatment, the target materials are pure metal tungsten and pure metal nickel, and the substrate temperature is adjusted to 100°C, the ambient temperature is in the range of 200-300°C, and the sputtering distance is 10 cm.

[0057] Those skilled in the art will clearly understand that for the sake of convenience and brevity, the division of the above-mentioned functional modules is only used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0058] An embodiment of the present invention provides a computer-readable storage medium storing a computer program capable of being loaded and executed by a processor for a method for coating an electrochromic device.

[0059] Computer storage media include, for example, various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0060] Based on the same inventive concept, an embodiment of the present invention provides a smart terminal including a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute the electrochromic device coating process.

[0061] Those skilled in the art will clearly understand that for the sake of convenience and brevity, the division of the above-mentioned functional modules is only used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0062] The following are the specific experimental data in Tables 1 to 4-2 of the examples of this application:

[0063] 1mm large glass 200nm 250nm 300nm 350nm Square resistance 15 12 8 5 Transmittance 81％ 79％ 77％ 76％ b-value 0.4 0.7 1.2 1.5

[0064] Table 1

[0065]

[0066]

[0067] Table 2

[0068]

[0069] Table 3

[0070]

[0071] Table 4-1

[0072]

[0073] Table 4-2

[0074] The above are all preferred embodiments of the present application and are not intended to limit the scope of protection of this application. Unless otherwise stated, any feature disclosed in this specification (including the abstract and tables) may be replaced by other equivalent or similar features. In other words, unless otherwise stated, each feature is merely an example of a series of equivalent or similar features.

Claims

1. A coating process for an electrochromic device, characterized in that: The following steps are involved: Step 1: pre-treatment of the substrate, cleaning the surface of the flexible substrate by ultrasonic cleaning and plasma treatment; Step 2: Deposition of conductive layer: depositing an indium tin oxide (ITO) conductive layer on the substrate at a deposition temperature of 100 to 380°C, a thickness of 200 to 350 nm, and a vacuum degree of ≤10 -5 Pa; Step 3: Electrochromic layer deposition: a tungsten oxide (WO3) layer and a nickel oxide (NiO) layer are sequentially deposited by magnetron sputtering, with the NiO and WO3 film thickness ratio controlled to achieve a NiO / W ratio of 0.25 to 0.

357. Step 4: annealing treatment. The first annealing treatment is performed at 200-500° C. for 200-300 seconds. The second annealing treatment is performed at 400° C. for 200-800 seconds.

2. The electrochromic device coating process according to claim 1, characterized in that: In step 3, the NiO / W ratio is preferably 0.25-0.357, and is achieved by magnetron sputtering a pure metal nickel target and a tungsten target, with a sputtering spacing of 5-15 cm and a substrate temperature of 100-300°C.

3. The electrochromic device coating process according to claim 1, characterized in that: In step 2, the first annealing temperature is 200° C., and the annealing time is 300 seconds; the second annealing temperature is 400° C., and the annealing time is 500 seconds.

4. The electrochromic device coating process according to claim 1, characterized in that: In step 4, the total duration of the first annealing and the second annealing is 500 to 1100 seconds, and the temperature gradient is low at first and then high.

5. The electrochromic device coating process according to claim 4, characterized in that: Between Steps 3 and 4 also include: Transition metal oxide doping treatment, co-sputtering zirconium oxide (ZrO) in the nickel oxide layer, the power ratio of the nickel target to the ZrO target is 1:0.5 to 1:1.2, and the transmittance of the film layer after doping is increased to 12.7% to 77.6%.

6. The electrochromic device coating process according to claim 5, characterized in that: The doping adopts a sandwich co-sputtering method, the sputtering power of the nickel target and the ZrO target are independently controlled, and the total doping ratio is NiO:ZrO=9:1-7:

3.

7. The electrochromic device coating process according to claim 1, characterized in that: The thickness of the conductive layer is preferably 250-300 nm, the square resistance is ≤12Ω / sq, and the initial transmittance is ≥72%.

8. A method for coating an electrochromic device, characterized in that: include: Collecting nickel oxide / tungsten oxide ratio parameters during electrochromic layer deposition, and calculating multiple sets of optimized ratio parameters according to a preset decreasing ratio; The target material is subjected to magnetron sputtering treatment based on the optimized ratio parameters to obtain an electrochromic layer, and the color change value of the electrochromic layer is analyzed to see whether it meets the preset base color parameters; When the preset background color parameters are not met, the optimized ratio parameters are adjusted downward and optimized ratio feedback parameters are generated.

9. The electrochromic device coating method according to claim 8, characterized in that: During the magnetron sputtering treatment, the target materials are pure metal tungsten and pure metal nickel, and the substrate temperature is adjusted to 100° C., the ambient temperature is in the range of 200-300° C., and the sputtering distance is 10 cm.

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