Laser radar diaphragm preparation method and laser radar

Abstract

The invention relates to the technical field of laser radars, in particular to a preparation method of a laser radar diaphragm and a laser radar. The preparation method comprises the following steps: providing a substrate; continuously depositing a first black film layer, a transparent conductive film and an AR coating on the back surface of the substrate by adopting an integrated coating process to prepare a middleware; wherein the first black film layer is used for regulating and controlling a transmitted light wave band; and annealing treatment is conducted on the middleware, and according to the technological parameters of the annealing treatment, the annealing temperature ranges from 170 DEG C to 190 DEG C, and the annealing time ranges from 60 min to 120 min. The laser radar diaphragm prepared by the preparation method provided by the invention is more compact in film layer structure, higher in adhesive force between film layers, higher in current conduction stability and better in product etching resistance.

Description

Technical Field

[0001] This application relates to the field of lidar technology, and in particular to a method for preparing a lidar window and a lidar system. Background Technology

[0002] With the development of driver assistance technology in the automotive field, the performance requirements for auxiliary detection systems are becoming increasingly stringent. Among these, vehicle-mounted lidar, as an important component of auxiliary detection systems, has become a research hotspot. Vehicle-mounted lidar transmits and receives laser signals, thereby influencing driving operations based on these signals. To achieve high-precision detection of target objects, a lidar window is typically placed on the outside of the lidar imaging system, and this window is coated to ensure high transmittance of the emitted laser wavelength.

[0003] Traditionally, a segmented coating process is used for coating treatment. However, the segmented coating process has the following drawbacks: the interface is prone to oxidation and the film layer is contaminated during the workpiece transfer process, resulting in a decrease in the adhesion between layers, complex process operation and low production efficiency. Summary of the Invention

[0004] Based on this, this application provides a method for preparing a lidar window and a lidar, wherein the film layer is not easily contaminated during the preparation process, the operation is simple, and the production efficiency is high.

[0005] The first aspect of this application provides a method for preparing a lidar window, comprising the following steps:

[0006] Provide substrate;

[0007] An intermediate component is fabricated by continuously depositing a first black film layer, a transparent conductive film, and an AR coating on the back side of a substrate using an integrated coating process; wherein, the first black film layer is used to control the transmitted light waveband.

[0008] The intermediate parts are annealed. The annealing process parameters include: annealing temperature of 170℃~190℃ and annealing time of 60min~120min.

[0009] In some embodiments, the annealing process includes: heating to 170°C~190°C within 30 minutes, annealing for 60 minutes~120 minutes, and then cooling to 18°C~25°C.

[0010] In some embodiments, the preparation method includes at least one of the following features: (1) the first black film layer includes at least one of silicon hydride, silicon oxide, silicon nitride, silicon oxynitride, titanium oxide, niobium oxide, tantalum oxide, silicon, antimony oxide, zinc oxide, tin oxide, chromium oxide, hafnium oxide, zinc sulfide, cerium oxide, zirconium oxide, lead fluoride, aluminum oxide, tungsten oxide, magnesium oxide, yttrium oxide, cerium fluoride, magnesium fluoride, and sodium aluminum fluoride; (2) the transparent conductive film includes at least one of ITO transparent conductive film, AZO transparent conductive film, graphene transparent conductive film, zinc oxide transparent conductive film, and tin oxide transparent conductive film.

[0011] In some embodiments, the method for preparing a lidar window further includes the following steps: cutting and morphological processing of the substrate to prepare a substrate.

[0012] In some embodiments, the method for preparing the lidar window further includes the step of strengthening the substrate.

[0013] In some embodiments, the strengthening treatment includes at least one of the following features: (1) the strengthening agent is a molten salt; optionally, the molten salt includes one or more of potassium salt, sodium salt, rubidium salt, cesium salt and lithium salt; (2) the strengthening temperature is 300℃~690℃; (3) the strengthening time is 0.01h~168h.

[0014] In some embodiments, the method for preparing the lidar window further includes the following step: preparing a second black film layer on the front side of the substrate.

[0015] In some embodiments, the method for preparing the lidar window includes at least one of the following features: (1) the thickness of the first black film layer is 1900nm~2100nm; optionally, the thickness of the second black film layer is 1900nm~2100nm; (2) the thickness of the transparent conductive film is 15nm~25nm; (3) the thickness of the AR coating is 600nm~800nm.

[0016] In some embodiments, the method for preparing the lidar window further includes the following step: etching the annealed AR coating.

[0017] In some embodiments, the etching process includes at least one of the following features: (1) etching the AR coating by an ICP plasma process; (2) the etching time is 60 min to 130 min.

[0018] The second aspect of this application provides a lidar, including a lidar window prepared by the preparation method provided in the first aspect of this application.

[0019] Compared with the prior art, this application has the following beneficial effects:

[0020] This application employs an integrated coating process to continuously deposit a first black film layer, a transparent conductive film, and an AR coating layer on the back side of a substrate. The entire coating process is carried out continuously under the same vacuum environment, avoiding water vapor and dust contamination caused by vacuum breaking in segmented processes. This results in cleaner interfaces between film layers, improved adhesion between layers, and higher production efficiency. Furthermore, by uniformly controlling the deposition parameters, the stress matching between film layers is improved, and the operation is simple.

[0021] However, during the preparation process using the integrated coating process, researchers found that due to the differences in the film materials of the first black film layer, the transparent conductive film, and the AR coating layer, and because the integrated coating equipment does not contain heating elements, the integrated coating process did not bake the prepared multilayer film at high temperature. As a result, the obtained multilayer film has a loose structure, poor film density, and the bonding force between layers needs to be further improved. It also has poor etching resistance and conductivity.

[0022] Based on the problems existing in the integrated coating process, this application adds an annealing step after the integrated coating process and studies the relevant process parameters of the annealing treatment. If the annealing temperature is too low or the annealing time is too short, the atomic diffusion energy is insufficient, failing to effectively eliminate the porosity defects generated during the coating process. This results in residual internal stress within the film, low density, and difficulty in atomic diffusion across layers, leading to a porous film. If the annealing temperature is too high or the annealing time is too long, after the initial densification, excessive grain growth is likely in the later stages, causing a decrease in density; increased thermal stress leads to a decrease in interfacial adhesion. Therefore, this application improves the density of the film structure and enhances the adhesion between film layers by setting an annealing step, an annealing temperature of 170℃~190℃, and an annealing time of 60min~120min. This also enhances the stability of current conduction between film layers, which is beneficial for improving the etching resistance of the product. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of a method for preparing a lidar window in one embodiment of this application.

[0025] Figure 2 This is a schematic diagram of a lidar window in one embodiment of this application.

[0026] Figure 3 This is a schematic diagram of a lidar window in another embodiment of this application.

[0027] Figure 4 This is a schematic diagram of a lidar window in another embodiment of this application.

[0028] Figure 5 This is a schematic diagram of a lidar window in another embodiment of this application.

[0029] Figure 6 This is a SEM image of the product prepared in Example 1 of this application.

[0030] Figure 7 This is a SEM image of the product prepared in Example 2 of this application.

[0031] Figure 8 This is a SEM image of the product prepared in Example 3 of this application.

[0032] Figure 9 This is a SEM image of the product prepared in Example 4 of this application.

[0033] Figure 10 This is a SEM image of the product prepared in Example 5 of this application.

[0034] Figure 11 This is a SEM image of the product prepared in Example 6 of this application.

[0035] Figure 12 This is a SEM image of the product prepared in Example 7 of this application.

[0036] Figure 13 This is a SEM image of the product prepared in Example 8 of this application.

[0037] Figure 14 This is a SEM image of the product prepared in Example 9 of this application.

[0038] Figure 15 This is a SEM image of the product prepared in Example 10 of this application.

[0039] Figure 16 This is a SEM image of the product prepared in Example 11 of this application.

[0040] Figure 17 This is a SEM image of the product prepared in Comparative Example 1 of this application.

[0041] Figure 18 This is a SEM image of the product prepared in Comparative Example 2 of this application.

[0042] Figure 19 This is a SEM image of the product prepared in Comparative Example 3 of this application.

[0043] Figure 20 This is a SEM image of the product prepared in Comparative Example 4 of this application.

[0044] Figure 21 This is an appearance diagram of the product prepared in Example 1 of this application.

[0045] Figure 22 This is an appearance diagram of the product prepared in Example 2 of this application.

[0046] Figure 23 This is an appearance diagram of the product prepared in Example 3 of this application.

[0047] Explanation of reference numerals in the attached figures

[0048] 10. LiDAR window; 100. Substrate; 210. First black film layer; 220. Second black film layer; 300. Transparent conductive film; 400. AR coating; 500. AF coating. Detailed Implementation

[0049] A detailed reference is now provided to embodiments of this application, one or more of which are described below. Each embodiment is provided for explanation and not for limitation. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to this application without departing from its scope or spirit. For example, features described or illustrated as part of one embodiment may be used in another embodiment to produce further embodiments.

[0050] Therefore, this application is intended to cover such modifications and variations falling within the scope of the appended claims and their equivalents. Other objects, features, and aspects of this application are disclosed in or will be apparent from the following detailed description. It will be understood by those skilled in the art that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of this application.

[0051] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0052] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0053] In this article, when referring to units of data ranges, if a unit is only followed by the right endpoint, it means that the units of the left and right endpoints are the same.

[0054] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0055] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0056] Unless otherwise specified, all steps in this application may be performed sequentially or randomly, preferably sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0057] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0058] like Figure 1 As shown, the first aspect of this application provides a method for fabricating a lidar window 10, comprising the following steps:

[0059] S1. Provide substrate 100.

[0060] S2. An intermediate component is prepared by continuously depositing a first black film layer 210, a transparent conductive film 300, and an AR coating layer 400 on the back side of a substrate 100 using an integrated coating process.

[0061] S3. Anneal the intermediate parts at 170℃~190℃ for 60min~120min.

[0062] In S2, the first black film layer 210 is used to control the transmitted light wave band.

[0063] This application employs an integrated coating process to continuously deposit a first black film layer 210, a transparent conductive film 300, and an AR coating layer 400 on the back side of a substrate 100. The entire coating process is carried out continuously under the same vacuum environment, avoiding water vapor and dust contamination caused by vacuum breaking in segmented processes. The interfaces between film layers are cleaner, improving the bonding force between layers and increasing production efficiency. By uniformly controlling the deposition parameters, the stress matching between film layers is improved, and the operation is simple.

[0064] However, during the preparation process using the integrated coating process, researchers found that due to the differences in the film materials of the first black film layer, the transparent conductive film, and the AR coating layer, and because the integrated coating equipment does not contain heating elements, the integrated coating process did not bake the prepared multilayer film at high temperature. As a result, the obtained multilayer film has a loose structure, poor film density, and the bonding force between layers needs to be further improved. It also has poor etching resistance and conductivity.

[0065] Based on the problems existing in the integrated coating process, this application adds an annealing step after the integrated coating process and studies the relevant process parameters of the annealing treatment. If the annealing temperature is too low or the annealing time is too short, the atomic diffusion energy is insufficient, failing to effectively eliminate the porosity defects generated during the coating process, resulting in residual internal stress within the film, low density, and difficulty in atomic diffusion across layers, leading to a porous film. If the annealing temperature is too high or the annealing time is too long, after the initial densification is completed, excessive grain growth is likely in the later stages, which actually reduces the density; thermal stress is also intensified, leading to a decrease in interfacial adhesion. Therefore, this application improves the density of the film structure and enhances the adhesion between film layers by setting an annealing step, an annealing temperature of 170℃~190℃, and an annealing time of 60min~120min. This also enhances the stability of current conduction between film layers and improves the etching resistance of the product.

[0066] In some embodiments, S2 includes: placing the substrate 100 in a continuous magnetron sputtering equipment cavity, and continuously depositing a first black film layer 210, a transparent conductive film 300, and an AR coating layer 400 on the back side of the substrate 100 by magnetron sputtering to prepare an intermediate component.

[0067] In some implementations, the vacuum level of the equipment cavity during magnetron sputtering is 0.4 Pa to 0.7 Pa.

[0068] In some embodiments, the annealing process includes: heating to 170°C to 190°C within 20 to 30 minutes, and then cooling to 18°C ​​to 24°C after 60 to 120 minutes. Further, the temperature is raised to 170°C to 190°C within 30 minutes.

[0069] If the heating time is too long, it will reduce production efficiency; if the heating time is too short, it will result in poor temperature uniformity in different areas of the annealing equipment chamber, which will lead to uneven distribution of material hardness and strength, and a decrease in local brittleness or toughness. At the same time, the temperature difference itself will generate new thermal stress inside the material, which will be superimposed on the original residual stress, increasing the risk of material deformation.

[0070] In some embodiments, the annealing process includes: placing the intermediate part in an annealing furnace, heating it to 170°C~190°C within 30 minutes, opening the furnace door to cool it down after 60 minutes~120 minutes, removing the product when the temperature drops below 60°C, and continuing to cool it down to 18°C~24°C.

[0071] In some implementations, the annealing time is 90 min to 120 min.

[0072] In some embodiments, the first black film layer 210 includes at least one of silicon hydride, silicon oxide, silicon nitride, silicon oxynitride, titanium oxide, niobium oxide, tantalum oxide, silicon, antimony oxide, zinc oxide, tin oxide, chromium oxide, hafnium oxide, zinc sulfide, cerium oxide, zirconium oxide, lead fluoride, aluminum oxide, tungsten oxide, magnesium oxide, yttrium oxide, cerium fluoride, magnesium fluoride, and sodium aluminum fluoride. Further, the first black film layer 210 includes at least one of silicon hydride and silicon oxide.

[0073] In some embodiments, the thickness of the first black film layer 210 is 1900 nm to 2100 nm. Further, the thickness of the first black film layer 210 is 2000 nm. Within the thickness range of the first black film layer 210, the number of layers of the first black film layer 210 can be set according to actual needs.

[0074] In one specific embodiment, the first black film layer 210 has 30 layers.

[0075] In some embodiments, the thickness of the transparent conductive film 300 is 15 nm to 25 nm. Further, the thickness of the transparent conductive film 300 is 20 nm. Within the thickness range of the transparent conductive film 300, the number of layers of the transparent conductive film 300 can be set according to actual needs.

[0076] In one specific embodiment, the transparent conductive film 300 has one layer.

[0077] In some embodiments, the transparent conductive film 300 includes at least one selected from ITO (indium tin oxide) transparent conductive film 300, AZO (aluminum zinc oxide) transparent conductive film 300, graphene transparent conductive film 300, zinc oxide transparent conductive film 300, and tin oxide transparent conductive film 300. Further, the transparent conductive film 300 is an ITO (indium tin oxide) transparent conductive film 300.

[0078] In some embodiments, the transparent conductive film 300 is used to connect to an external power supply and control system via a circuit or flexible circuit board made of one or more of silver paste, carbon paste, copper paste and gold paste at its edges.

[0079] In some embodiments, the AR coating 400 comprises one or more of the following: silicon hydride, silicon oxide, silicon nitride, silicon oxynitride, titanium oxide, niobium oxide, tantalum oxide, silicon, antimony oxide, zinc oxide, tin oxide, chromium oxide, hafnium oxide, zinc sulfide, cerium oxide, zirconium oxide, lead fluoride, aluminum oxide, tungsten oxide, magnesium oxide, yttrium oxide, cerium fluoride, magnesium fluoride, and sodium aluminum fluoride. Further, the AR coating 400 comprises at least one of silicon hydride and silicon oxide.

[0080] In some embodiments, the thickness of the AR coating 400 is 600 nm to 800 nm. Further, the thickness of the AR coating 400 is 700 nm. Within the thickness range of the AR coating 400, the number of layers of the AR coating 400 can be set according to actual needs.

[0081] In one specific embodiment, the AR coating 400 has 3 layers.

[0082] In some embodiments, the first black film layer 210 on the back side of the substrate 100 has a transmittance of 0% to 60% for the 380nm to 680nm wavelength band and a transmittance of 30% to 99.8% for the 860nm to 1600nm wavelength band.

[0083] In some embodiments, the combined layer of transparent conductive film and AR coating 400 on the back side of substrate 100 has a transmittance of 0% to 60% in the 380nm to 680nm wavelength band and a transmittance of 30% to 99.8% in the 860nm to 1600nm wavelength band.

[0084] In some embodiments, the combined layer of the first black film layer 210, the transparent conductive film and the AR coating layer 400 on the back side of the substrate 100 has a transmittance of 0% to 60% in the 380nm to 680nm wavelength band and a transmittance of 30% to 99.8% in the 860nm to 1600nm wavelength band.

[0085] In some embodiments, the method for preparing the lidar window 10 further includes the following steps: slitting and morphological processing of the substrate to prepare the substrate 100, in order to obtain a substrate 100 with high surface precision.

[0086] In some embodiments, the preparation of substrate 100 by slitting and morphological processing of the substrate includes the following steps: processing the substrate by slitting, CNC machining, hot bending, grinding or polishing to obtain substrate 100, and the obtained substrate 100 has high viewing angle capability.

[0087] In some embodiments, the substrate includes one or more of glass, sapphire, quartz, and transparent ceramics. The glass includes one or more of high-alumina-silicon glass, lithium aluminum-silicon glass, soda-lime glass, microcrystalline glass, and borosilicate glass. In another embodiment, the glass may also be optical glass.

[0088] In some embodiments, the method for preparing the lidar window 10 further includes the step of strengthening the substrate 100.

[0089] In some embodiments, the strengthening agent used to strengthen the substrate 100 is a molten salt. The molten salt includes one or more of potassium salts, sodium salts, rubidium salts, cesium salts, and lithium salts. For example, potassium salts include potassium nitrate, sodium salts include sodium nitrate, and lithium salts include lithium nitrate.

[0090] In some embodiments, the strengthening temperature for strengthening the substrate 100 is 300°C to 690°C, including but not limited to 300°C, 400°C, 500°C, 600°C, and 690°C. Further, the strengthening temperature is 350°C to 690°C. Even further, the strengthening temperature is 380°C to 460°C.

[0091] In some embodiments, the strengthening time for strengthening the substrate 100 is 0.01 h to 168 h. Further, the strengthening time is 1 h to 30 h. Even further, the strengthening time is 2 h to 16 h.

[0092] It is understandable that the strengthening process must be performed at least once. It should be noted that the above parameters (strengthening temperature, strengthening time) can be the same or different during multiple strengthening processes.

[0093] In some embodiments, strengthening the substrate 100 includes: placing the preheated substrate 100 in molten salt, the molten salt including one or more of potassium salt, sodium salt, rubidium salt, cesium salt and lithium salt; strengthening temperature of 300°C to 690°C; strengthening time of 0.01h to 168h; and strengthening treatment at least once.

[0094] This application effectively improves the overall impact resistance of the lidar window 10 by strengthening the substrate 100.

[0095] In some embodiments, the method for fabricating the lidar window 10 further includes the following step: fabricating a second black film layer 220 on the front side of the substrate 100.

[0096] In some embodiments, the method for fabricating the lidar window 10 further includes the following steps: fabricating an AR coating 400 and / or an AF coating 500 on the front side of the substrate 100.

[0097] In some embodiments, the method for preparing the lidar window 10 further includes the following steps: preparing a second black film layer 220 on the front side of the substrate 100, and preparing an AR coating layer 400 and / or an AF coating layer 500 on the surface of the second black film layer 220 away from the substrate 100.

[0098] This application prepares an AR coating 400 and / or an AF coating 500 on the front side of the lidar window 10 to assist the lidar window 10 in achieving low reflection, high hardness of the outer surface, and anti-fouling and anti-fingerprint properties on the outer surface.

[0099] In some embodiments, the second black film layer 220 includes at least one of silicon hydride, silicon oxide, silicon nitride, silicon oxynitride, titanium oxide, niobium oxide, tantalum oxide, silicon, antimony oxide, zinc oxide, tin oxide, chromium oxide, hafnium oxide, zinc sulfide, cerium oxide, zirconium oxide, lead fluoride, aluminum oxide, tungsten oxide, magnesium oxide, yttrium oxide, cerium fluoride, magnesium fluoride, and sodium aluminum fluoride.

[0100] In some embodiments, the thickness of the second black film layer 220 is 1900 nm to 2100 nm.

[0101] In some embodiments, the method further includes the step of etching the AR coating 400 on the front side of the substrate 100. In some embodiments, the AR coating 400 on the front side of the substrate 100 is etched using an ICP plasma dry etching process.

[0102] In some embodiments, the etching process takes 60 to 130 minutes. Further, the etching process takes 75 to 120 minutes.

[0103] It should be noted that the etching process time of 60 minutes refers to the process of screen printing etching paste (standing for 60 minutes), spraying, cleaning, screen printing etching paste (standing for 60 minutes), spraying, cleaning, screen printing silver paste, and screen printing protective oil.

[0104] The second aspect of this application provides a lidar, including a lidar window 10 prepared by the preparation method provided in the first aspect of this application.

[0105] In some implementations, such as Figure 2 As shown, Figure 2 This is a schematic diagram of a lidar window 10 provided in an embodiment of this application. A lidar window 10 includes a substrate 100, and a first black film layer 210, a transparent conductive film 300, and an AR coating layer 400 sequentially disposed on the back side of the substrate 100. The first black film layer 210 is located between the substrate 100 and the transparent conductive film 300.

[0106] In some implementations, such as Figure 3 As shown, the front side of the substrate 100 is provided with an AR coating 400 and / or an AF coating 500. When the front side of the substrate 100 is provided with an AR coating 400 and an AF coating 500, the AR coating 400 is located between the substrate 100 and the AF coating 500.

[0107] In some implementations, such as Figure 4 As shown, the front side of the substrate 100 is provided with a second black film layer 220 and an AR coating layer 400. The second black film layer 220 is located between the substrate 100 and the AR coating layer 400.

[0108] In some implementations, such as Figure 5 As shown, the front side of the substrate 100 is provided with a second black film layer 220, an AR coating layer 400, and an AF coating layer 500. The second black film layer 220, the AR coating layer 400, and the AF coating layer 500 are sequentially distributed along a direction away from the substrate 100. Furthermore, this application provides the following specific embodiments and comparative examples to further illustrate the specific implementation of this application and its advantages.

[0109] Example 1

[0110] High-aluminosilicate glass with a thickness of 2mm to 5mm is selected as the substrate. After cutting, CNC machining, hot bending, and contour grinding of the substrate, a high-precision substrate 100 is obtained through grinding and polishing.

[0111] The preheated substrate 100 was placed in potassium nitrate molten salt and strengthened at a strengthening temperature of 400°C for 10 hours.

[0112] A substrate 100 is placed in a continuous magnetron sputtering apparatus cavity, and an intermediate component is fabricated by continuously depositing a 2000 nm thick first black film layer 210 (30 layers), a 20 nm thick transparent conductive film 300 (1 layer), and a 700 nm thick AR coating layer 400 (3 layers) on the back side of the substrate 100 via magnetron sputtering. The vacuum level of the apparatus cavity is 0.4 Pa; the material of the first black film layer 210 is silicon oxide; the transparent conductive film 300 is an ITO transparent conductive film; and the material of the AR coating layer 400 is silicon oxide.

[0113] Place the intermediate part in the annealing furnace, heat it to 180°C for 30 minutes, and after 90 minutes, open the furnace door to cool it down. When the temperature drops to 60°C, take out the product and continue to cool it down to 24°C.

[0114] The AR coating 400 on the front side of the substrate 100 in the above product was etched using an ICP plasma dry etching process. The etching time was 60 minutes.

[0115] Example 2

[0116] The preparation process of this embodiment is basically the same as that of embodiment 1. The main difference is that in embodiment 2, after heating to 180°C, the temperature is kept for 60 minutes.

[0117] Example 3

[0118] The preparation process of this embodiment is basically the same as that of embodiment 1. The main difference is that in embodiment 3, after heating to 180°C, the temperature is kept for 120 minutes.

[0119] Example 4

[0120] The preparation process of this embodiment is basically the same as that of embodiment 1. The main difference is that in embodiment 4, after heating to 170°C, the temperature is held for 90 minutes.

[0121] Example 5

[0122] The preparation process of this embodiment is basically the same as that of embodiment 1. The main difference is that in embodiment 5, after heating to 190°C, the temperature is held for 90 minutes.

[0123] Example 6

[0124] The preparation process of this embodiment is basically the same as that of Embodiment 1. The main difference is that the etching time in Embodiment 6 is 75 min.

[0125] Example 7

[0126] The preparation process of this embodiment is basically the same as that of embodiment 1. The main difference is that the etching time in embodiment 7 is 90 min.

[0127] Example 8

[0128] The preparation process of this embodiment is basically the same as that of embodiment 2. The main difference is that the etching time in embodiment 8 is 100 min.

[0129] Example 9

[0130] The preparation process of this embodiment is basically the same as that of embodiment 1, the main difference being that the etching time in embodiment 9 is 120 min.

[0131] Example 10

[0132] The preparation process of this embodiment is basically the same as that of embodiment 2, the main difference being that the etching time in embodiment 10 is 130 min.

[0133] Example 11

[0134] The preparation process of this comparative example is basically the same as that of Example 1, except that the etching time in Example 11 is 140 min.

[0135] Comparative Example 1

[0136] The preparation process of this comparative example is basically the same as that of Example 1. The main difference is that the intermediate part was not annealed in Comparative Example 1.

[0137] Comparative Example 2

[0138] The preparation process of this comparative example is basically the same as that of Example 1. The main difference is that in Comparative Example 2, after heating to 180°C, the temperature is kept for 30 minutes.

[0139] Comparative Example 3

[0140] The preparation process of this comparative example is basically the same as that of Example 1. The main difference is that in Comparative Example 3, after heating to 180°C, it is kept at that temperature for 130 minutes.

[0141] Comparative Example 4: The preparation process of this comparative example is basically the same as that of Example 1. The main difference is that the heating rate is different in Comparative Example 4. Specifically, the intermediate is placed in an annealing furnace and heated to 180°C in 35 minutes. After 90 minutes, the furnace door is opened to cool down. When the temperature drops to 60°C, the product is taken out and the temperature is further cooled down to 24°C.

[0142] The relevant parameters in Examples 1-11 and Comparative Examples 1-4 are summarized in Table 1 below.

[0143] Table 1

[0144]

[0145] like Figures 6-16 The images shown are SEM images of the products prepared in Examples 1-11 of this application. Figures 17-20 The images shown are SEM images of the products prepared in Comparative Examples 1-4 of this application. Figures 21-23 The figures shown are appearance diagrams of the products prepared in Examples 1 to 3 of this application.

[0146] according to Figure 6 (Example 1) Figure 11 (Example 6) Figure 12 (Example 7) Figure 14 (Example 9) and Figure 16 (Example 11) By comparison, it can be seen that when the annealing temperature (180°C) and the holding time (90 min) remain unchanged, within a certain range, the AR residue on the surface of the lidar window decreases as the etching time increases. However, when the etching time is too long, the ITO will be damaged.

[0147] according to Figure 7 (Example 2) Figure 13 (Example 8) and Figure 15 (Example 10) Comparison shows that when the annealing temperature (180°C) and holding time (60 min) remain unchanged, within a certain range, the AR residue on the surface of the lidar window decreases with the increase of etching time. However, when the etching time is too long, the ITO will be damaged.

[0148] according to Figure 6 (Example 1) Figure 7 (Example 2) Figure 8 (Example 3) Figure 18 (Comparative Example 2) and Figure 19 (Comparative Example 3) It can be seen that when the annealing temperature (180℃) and etching time remain unchanged (60min), the AR residue on the surface of the lidar window plate shows a trend of first decreasing and then increasing as the holding time increases. Moreover, if the holding time is too long, it will waste production capacity and increase energy consumption.

[0149] according to Figure 6 (Example 1) Figure 9 (Example 4) and Figure 10 (Example 5) It can be seen that when the holding time (90 min) and etching time (60 min) remain unchanged, the AR residue on the surface of the lidar window is less when the annealing temperature is in the range of 170℃~190℃.

[0150] according to Figures 21-23 (Examples 1-3) Comparison shows that, under the premise that the etching time (60 min) and annealing temperature (180 °C) remain unchanged, from the appearance perspective, the etching effect on the lidar window prepared by holding for 60 min is worse than that of holding for 90 min and 120 min, and there is obvious AR residue at the end of the ITO film layer.

[0151] Test case

[0152] ITO resistance was tested on the etched area of ​​the lidar window. The results are shown in Table 2 below.

[0153] Table 2

[0154]

[0155]

[0156] The method for fabricating a lidar window provided in this application involves an annealing process following an integrated coating process. This process heats and crystallizes the transparent conductive film, resulting in a change in density and improved resistance to chemical etching. During the coating process, the atoms or molecules in the transparent conductive film may be in a relatively disordered state, forming an amorphous or partially crystalline structure. When annealing is performed, the provided heat energy allows the atoms to acquire sufficient energy for migration and rearrangement. Under suitable temperature and time conditions, the atoms gradually form a regular lattice structure, thereby achieving crystallization. After crystallization, the film layer has better density, better resistance to chemical etching, and stable conductivity after etching, thus improving the conductivity yield after chemical etching.

[0157] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0158] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for preparing a lidar window, characterized in that, Includes the following steps: Provide substrate; An intermediate component is fabricated by continuously depositing a first black film layer, a transparent conductive film, and an AR coating layer on the back side of the substrate using an integrated coating process; wherein, the first black film layer is used to control the transmitted light waveband. The intermediate component is subjected to annealing treatment, and the process parameters of the annealing treatment include: annealing temperature of 170℃~190℃ and annealing time of 60min~120min.

2. The method for preparing a lidar window according to claim 1, characterized in that, The annealing process includes: heating to 170℃~190℃ within 20min~30min, and then cooling to 18℃~25℃ after 60min~120min.

3. The method for preparing a lidar window according to claim 1, characterized in that, The preparation method includes at least one of the following features: (1) The first black film layer includes at least one of the following: silicon hydride, silicon oxide, silicon nitride, silicon oxynitride, titanium oxide, niobium oxide, tantalum oxide, silicon, antimony oxide, zinc oxide, tin oxide, chromium oxide, hafnium oxide, zinc sulfide, cerium oxide, zirconium oxide, lead fluoride, aluminum oxide, tungsten oxide, magnesium oxide, yttrium oxide, cerium fluoride, magnesium fluoride, and sodium aluminum fluoride; (2) The transparent conductive film includes at least one of ITO transparent conductive film, AZO transparent conductive film, graphene transparent conductive film, zinc oxide transparent conductive film, and tin oxide transparent conductive film.

4. The method for preparing a lidar window according to claim 1, characterized in that, It also includes the following steps: The substrate is subjected to a strengthening treatment.

5. The method for preparing a lidar window according to claim 4, characterized in that, The enhancement process includes at least one of the following features: (1) The reinforcing agent is molten salt; Optionally, the molten salt includes one or more of potassium salts, sodium salts, rubidium salts, cesium salts, and lithium salts; (2) The strengthening temperature is 300℃~690℃; (3) The reinforcement time is 0.01h to 168h.

6. The method for preparing a lidar window according to any one of claims 1 to 5, characterized in that, The method also includes the following step: preparing a second black film layer on the front side of the substrate; Optionally, the thickness of the second black film layer is 1900nm~2100nm.

7. The method for preparing a lidar window according to any one of claims 1 to 5, characterized in that, The method for preparing the lidar window includes at least one of the following features: (1) The thickness of the first black film layer is 1900nm~2100nm; (2) The thickness of the transparent conductive film is 15nm~25nm; (3) The thickness of the AR coating is 600nm~800nm.

8. The method for preparing a lidar window according to any one of claims 1 to 5, characterized in that, It also includes the following steps: The annealed AR coating is then etched.

9. The method for preparing a lidar window according to claim 8, characterized in that, Etching processes include at least one of the following features: (1) The AR coating is etched using an ICP plasma process; (2) The etching time is 60 min to 130 min.

10. A lidar, characterized in that, Including the lidar window sheet prepared by the preparation method according to any one of claims 1 to 9.

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